Compositions and methods for treating tumors

Abstract

Compositions and methods directed to treating tumors comprising administering an effective amount of one or more immune checkpoint inhibitors, and an effective amount of a PDE4 selective inhibitor. The compositions and methods have a significant tumor inhibiting effect.

Description

Technical Field

[0001] This application relates to the field of biomedicine, specifically to a composition and method for treating tumors. Background Technology

[0002] Malignant tumors are a serious threat to human health. Global cancer statistics in 2018 showed 18.19 million new cancer cases and 9.6 million cancer deaths worldwide. Taking colorectal cancer as an example, it accounts for 10.2% of all cancer cases and 9.2% of cancer deaths annually, meaning approximately 1.85 million new cases and 880,000 deaths each year. In my country, there are approximately 370,000 new colorectal cancer cases annually. Oxaliplatin is the primary treatment for colorectal cancer, with chemotherapy regimens including oxaliplatin combined with capecitabine and oxaliplatin combined with fluorouracil. However, these regimens have serious side effects, such as damage to the digestive and hematologic systems, and often lead to drug resistance. Furthermore, more than 30% of colorectal cancer patients are insensitive to platinum-based chemotherapy drugs. These findings indicate that while chemotherapy drugs are effective against tumors, they also exhibit varying degrees of toxicity or drug resistance, especially given the insensitivity of some cancer patients to these drugs. Therefore, finding more effective anti-tumor drugs and methods is a pressing issue that needs to be addressed. Summary of the Invention

[0003] This application provides a drug combination and method for treating tumors, primarily comprising administering an effective amount of a PDE4 (phosphodiesterase type 4) selective inhibitor. In some cases, the drug combination or method of this application further includes administering an effective amount of an immune checkpoint inhibitor. The drug combination or method of this application has one or more of the following effects: 1) avoiding the side effects of chemotherapy; 2) effectively inhibiting tumor (cell) growth, such as solid tumors (e.g., colorectal cancer), lymphoma, and / or hematologic malignancies; 3) inhibiting tumor cell metastasis (e.g., inhibiting liver metastasis); 4) having no significant effect on other physiological indicators of the subject (e.g., weight), and is therefore safe.

[0004] This application provides a pharmaceutical combination comprising:

[0005] a) An effective dose of an immune checkpoint inhibitor; and

[0006] b) An effective amount of a selective PDE4 inhibitor.

[0007] In some embodiments, the PDE4 selective inhibitor includes Apremilast, Cresaborole, Drotaverine, CC-1088, BPN14770, GSK356278, HT-0712, TAK-648, Zembrin, ASP9831, Etazolate, Piclamilast, Rolipram, Dipyridamole, Cilomilast, GSK256066, AWD12–281, Quinolyl oxazole, DC-TA-46, Filaminast, and / or Glaucine.

[0008] In some embodiments, the PDE4 selective inhibitor comprises a compound of formula I, a pharmaceutically acceptable salt thereof, or an N-oxide of pyridine or a salt thereof:

[0009]

[0010] Wherein, one of R1 and R2 is hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and the other of R1 and R2 is a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and

[0011] R3 is phenyl, pyridyl, a phenyl group substituted with R31, R32, and R33, or a pyridyl group substituted with R34, R35, R36, and R37, wherein: R31 is hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino, or C1-C4 alkylcarbonyl. R32 is hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl or C1-C4 alkoxy, R33 is hydrogen, halogen, C1-C4 alkyl or C1-C4 alkoxy, R34 is hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxy carbonyl or amino, R35 is hydrogen, halogen, amino or C1-C4 alkyl, R36 is hydrogen or halogen, and R37 is hydrogen or halogen.

[0012] In some implementations, wherein:

[0013] R1 is hydrogen, C1-C6-alkoxy, C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0014] R2 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0015] R3 is phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 is hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonylamino. R32 is hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl, or C1-C4-alkoxy; R33 is hydrogen, halogen, C1-C4-alkyl, or C1-C4-alkoxy; R34 is hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, or amino; R35 is hydrogen, halogen, amino, or C1-C4-alkyl; R36 is hydrogen or halogen; and R37 is hydrogen or halogen.

[0016] In some implementations, wherein:

[0017] R1 is hydrogen, C1-C6-alkoxy, C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0018] R2 is a methoxy group that is wholly or partially substituted with fluorine, and

[0019] R3 is phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 is hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonylamino. R32 is hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl, or C1-C4-alkoxy; R33 is hydrogen, halogen, C1-C4-alkyl, or C1-C4-alkoxy; R34 is hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, or amino; R35 is hydrogen, halogen, amino, or C1-C4-alkyl; R36 is hydrogen or halogen; and R37 is hydrogen or halogen.

[0020] In some implementations, wherein:

[0021] R1 is a C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, or benzoxy.

[0022] R2 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0023] R3 is phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 is hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonyl. The amino group, R32 is hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy, R33 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 is hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl or amino, R35 is hydrogen, halogen, amino or C1-C4-alkyl, R36 is hydrogen or halogen, and R37 is hydrogen or halogen.

[0024] In some implementations, wherein:

[0025] R1 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0026] R2 is hydrogen, C1-C6-alkoxy, C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group wholly or partially substituted with fluorine, and

[0027] R3 is phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 is hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonylamino. R32 is hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl, or C1-C4-alkoxy; R33 is hydrogen, halogen, C1-C4-alkyl, or C1-C4-alkoxy; R34 is hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, or amino; R35 is hydrogen, halogen, amino, or C1-C4-alkyl; R36 is hydrogen or halogen; and R37 is hydrogen or halogen.

[0028] In some implementations, wherein:

[0029] R1 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0030] R2 is a C3-C7-cycloalkylmethoxy or benzylmethoxy, and

[0031] R3 is phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 is hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonylamino. R32 is hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl, or C1-C4-alkoxy; R33 is hydrogen, halogen, C1-C4-alkyl, or C1-C4-alkoxy; R34 is hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, or amino; R35 is hydrogen, halogen, amino, or C1-C4-alkyl; R36 is hydrogen or halogen; and R37 is hydrogen or halogen.

[0032] In some implementations, wherein:

[0033] R1 is a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine.

[0034] R2 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0035] R3 is phenyl, pyridyl, phenyl substituted with R31, R32 and R33, or pyridyl substituted with R34, R35, R36 and R37, wherein: R31 is halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl; R32 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R33 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 is halogen or C1-C4-alkyl; R35 is hydrogen or halogen; R36 is hydrogen or halogen; and R37 is hydrogen or halogen.

[0036] In some implementations, wherein:

[0037] R1 is a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine.

[0038] R2 is a methoxy group that is wholly or partially substituted with fluorine, and

[0039] R3 is phenyl, pyridyl, phenyl substituted with R31, R32 and R33, or pyridyl substituted with R34, R35, R36 and R37, wherein: R31 is halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl; R32 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R33 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 is halogen or C1-C4-alkyl; R35 is hydrogen or halogen; R36 is hydrogen or halogen; and R37 is hydrogen or halogen.

[0040] In some implementations, wherein:

[0041] R1 is a C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, or benzoxy.

[0042] R2 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0043] R3 is phenyl, pyridyl, phenyl substituted with R31, R32 and R33, or pyridyl substituted with R34, R35, R36 and R37, wherein: R31 is halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl; R32 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R33 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 is halogen or C1-C4-alkyl; R35 is hydrogen or halogen; R36 is hydrogen or halogen; and R37 is hydrogen or halogen.

[0044] In some implementations, wherein:

[0045] R1 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0046] R2 is a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group wholly or partially substituted with fluorine, and

[0047] R3 is phenyl, pyridyl, phenyl substituted with R31, R32 and R33, or pyridyl substituted with R34, R35, R36 and R37, wherein: R31 is halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl; R32 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R33 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 is halogen or C1-C4-alkyl; R35 is hydrogen or halogen; R36 is hydrogen or halogen; and R37 is hydrogen or halogen.

[0048] In some implementations, wherein:

[0049] R1 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0050] R2 is a C3-C5-cycloalkylmethoxy or benzylmethoxy, and

[0051] R3 is phenyl, pyridyl, phenyl substituted with R31, R32 and R33, or pyridyl substituted with R34, R35, R36 and R37, wherein: R31 is halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl; R32 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R33 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 is halogen or C1-C4-alkyl; R35 is hydrogen or halogen; R36 is hydrogen or halogen; and R37 is hydrogen or halogen.

[0052] In some implementations, wherein:

[0053] R1 is a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine.

[0054] R2 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0055] R3 is 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0056] In some implementations, wherein:

[0057] R1 is a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine.

[0058] R2 is a methoxy group that is wholly or partially substituted with fluorine, and

[0059] R3 is 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0060] In some implementations, wherein:

[0061] R1 is a C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, or benzoxy.

[0062] R2 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0063] R3 is 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0064] In some implementations, wherein:

[0065] R1 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0066] R2 is a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group wholly or partially substituted with fluorine, and

[0067] R3 is 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0068] In some implementations, wherein:

[0069] R1 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0070] R2 is a C3-C5-cycloalkylmethoxy or benzylmethoxy, and

[0071] R3 is 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0072] In some implementations, wherein:

[0073] R1 is a difluoromethoxy group.

[0074] R2 is methoxy, ethoxy, isopropoxy, isobutoxy, cyclopentoxy, cyclopropylmethoxy, cyclobutylmethoxy, difluoromethoxy, or 2,2,2-trifluoroethoxy, and R3 is 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, or 2,6-dimethylphenyl. 2,6-Difluorophenyl, 2,6-Dichlorophenyl, 3,5-Dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl or 2,6-dichloropyridin-3-yl.

[0075] In some implementations, wherein:

[0076] R1 is a difluoromethoxy group.

[0077] R2 is methoxy, cyclopropylmethoxy, cyclobutylmethoxy, or difluoromethoxy, and

[0078] R3 is 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0079] In some implementations, wherein:

[0080] R1 is methoxy, n-propoxy, n-butoxy, cyclopropylmethoxy, or 2,2,2-trifluoroethoxy.

[0081] R2 is a difluoromethoxy group, and

[0082] R3 is 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0083] In some implementations, wherein:

[0084] R1 is a difluoromethoxy group.

[0085] R2 is cyclopropylmethoxy, and

[0086] R3 is 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0087] In some implementations, wherein:

[0088] R1 is a C3-C7-cycloalkoxy or C3-C7-cycloalkylmethoxy, and R2 is a C1-C4-alkoxy that is wholly or partially fluorinated; or R1 is a C1-C4-alkoxy that is wholly or partially fluorinated, and R2 is a C3-C7-cycloalkylmethoxy; and

[0089] R3 is phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 is hydroxyl, halogen, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, or C1-C4-alkylcarbonyloxy; R32 is hydrogen, hydroxyl, halogen, trifluoromethyl, C1-C4-alkyl, or C1-C4-alkoxy; R33 is hydrogen, halogen, C1-C4-alkyl, or C1-C4-alkoxy; R34 is hydroxyl, halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, or C1-C4-alkoxycarbonyl; R35 is hydrogen, halogen, amino, or C1-C4-alkyl; R36 is hydrogen or halogen; and R37 is hydrogen or halogen.

[0090] In some implementations, wherein:

[0091] R1 is a C3-C7-cycloalkoxy or a C3-C7-cycloalkylmethoxy.

[0092] R2 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0093] R3 is phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 is hydroxyl, halogen, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, or C1-C4-alkylcarbonyloxy; R32 is hydrogen, hydroxyl, halogen, trifluoromethyl, C1-C4-alkyl, or C1-C4-alkoxy; R33 is hydrogen, halogen, C1-C4-alkyl, or C1-C4-alkoxy; R34 is hydroxyl, halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, or C1-C4-alkoxycarbonyl; R35 is hydrogen, halogen, amino, or C1-C4-alkyl; R36 is hydrogen or halogen; and R37 is hydrogen or halogen.

[0094] In some implementations, wherein:

[0095] R1 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0096] R2 is a C3-C7-cycloalkylmethoxy group, and

[0097] R3 is phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 is hydroxyl, halogen, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, or C1-C4-alkylcarbonyloxy; R32 is hydrogen, hydroxyl, halogen, trifluoromethyl, C1-C4-alkyl, or C1-C4-alkoxy; R33 is hydrogen, halogen, C1-C4-alkyl, or C1-C4-alkoxy; R34 is hydroxyl, halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, or C1-C4-alkoxycarbonyl; R35 is hydrogen, halogen, or C1-C4-alkyl; R36 is hydrogen or halogen; and R37 is hydrogen or halogen.

[0098] In some implementations, wherein:

[0099] R1 is a C3-C5-cycloalkoxy or a C3-C5-cycloalkylmethoxy.

[0100] R2 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0101] R3 is phenyl, pyridyl, phenyl substituted with R31, R32 and R33, or pyridyl substituted with R34, R35, R36 and R37, wherein: R31 is halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl; R32 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R33 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 is halogen or C1-C4-alkyl; R35 is hydrogen or halogen; R36 is hydrogen or halogen; and R37 is hydrogen or halogen.

[0102] In some implementations, wherein:

[0103] R1 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0104] R2 is a C3-C5-cycloalkylmethoxy group, and

[0105] R3 is phenyl, pyridyl, phenyl substituted with R31, R32 and R33, or pyridyl substituted with R34, R35, R36 and R37, wherein: R31 is halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl; R32 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R33 is hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 is halogen or C1-C4-alkyl; R35 is hydrogen or halogen; R36 is hydrogen or halogen; and R37 is hydrogen or halogen.

[0106] In some implementations, wherein:

[0107] R1 is a C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, or benzoxy.

[0108] R2 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0109] R3 is 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0110] In some implementations, wherein:

[0111] R1 is a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0112] R2 is a C3-C5-cycloalkylmethoxy group, and

[0113] R3 is 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0114] In some implementations, wherein:

[0115] R1 is a difluoromethoxy group.

[0116] R2 is cyclopropylmethoxy, and

[0117] R3 is 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0118] In some embodiments, R1 is difluoromethoxy, R2 is cyclopropylmethoxy, and R3 is 3,5-dichloropyridin-4-yl.

[0119] In some embodiments, the PDE4 selective inhibitor comprises Roflumilast or a derivative thereof.

[0120] In some embodiments, the Roflumilast derivative comprises Benzanilide, 3-hydroxy-N-(3,5-dichloropyridin-4-yl)-4-methoxybenzamide, and / or 4-Methylbenzanilide.

[0121] In some embodiments, the immune checkpoint inhibitor includes antagonists of one or more of the following proteins: CTLA-4, PD-1, PD-L1, PD-L2, LAG-3, TIM-3, galactoglobulin 9, CEACAM-1, BTLA, CD69, galactoglobulin-1, TIGIT, CD113, GPR56, VISTA, 2B4, CD48, GARP, PD1H, LAIR1, TIM-1, and TIM-4.

[0122] In some embodiments, the immune checkpoint inhibitor includes PD-1 and / or PD-L1 antagonists.

[0123] In some embodiments, the antagonist of PD-1 and / or PD-L1 is capable of inhibiting the interaction between PD-1 and PD-L1.

[0124] In some embodiments, the PD-1 and / or PD-L1 antagonists include antibodies or antigen-binding fragments thereof that specifically bind to PD-1 and / or PD-L1.

[0125] In some embodiments, the antibody or antigen-binding fragment thereof that specifically binds to PD-1 and / or PD-L1 comprises HCDR3, and the HCDR3 comprises the amino acid sequence shown in any one of SEQ ID NO: 3, 13, 23 and 33.

[0126] In some embodiments, the antibody or antigen-binding fragment thereof that specifically binds to PD-1 and / or PD-L1 comprises HCDR2, and the HCDR2 comprises the amino acid sequence shown in any one of SEQ ID NO: 2, 12, 22 and 32.

[0127] In some embodiments, the antibody or antigen-binding fragment thereof that specifically binds to PD-1 and / or PD-L1 comprises HCDR1, and the HCDR1 comprises the amino acid sequence shown in any one of SEQ ID NO: 1, 11, 21, and 31.

[0128] In some embodiments, the antibody or antigen-binding fragment thereof that specifically binds to PD-1 and / or PD-L1 comprises VH, and the VH comprises the amino acid sequence shown in any one of SEQ ID NO: 7, 17, 27 and 37.

[0129] In some embodiments, the antibody or antigen-binding fragment thereof that specifically binds to PD-1 and / or PD-L1 comprises LCDR3, and the LCDR3 comprises the amino acid sequence shown in any one of SEQ ID NO: 6, 16, 26 and 36.

[0130] In some embodiments, the antibody or antigen-binding fragment thereof that specifically binds to PD-1 and / or PD-L1 comprises LCDR2, and the LCDR2 comprises the amino acid sequence shown in any one of SEQ ID NO: 5, 15, 25 and 35.

[0131] In some embodiments, the antibody or antigen-binding fragment thereof that specifically binds to PD-1 and / or PD-L1 comprises LCDR1, and the LCDR1 comprises the amino acid sequence shown in any one of SEQ ID NO: 4, 14, 24 and 34.

[0132] In some embodiments, the antibody or antigen-binding fragment thereof that specifically binds to PD-1 and / or PD-L1 comprises a VL, and the VL comprises an amino acid sequence shown in any one of SEQ ID NO: 8, 18, 28 and 38.

[0133] In some embodiments, the antibody that specifically binds to PD-1 and / or PD-L1 is selected from:

[0134] a) An antibody comprising the following heavy chain and light chain, wherein the heavy chain comprises the amino acid sequence shown in any one of SEQ ID NO: 9, 19, 29 and 39, and the light chain comprises the amino acid sequence shown in any one of SEQ ID NO: 10, 20, 30 and 40;

[0135] b) An antibody comprising a heavy chain and a light chain, wherein the heavy chain contains the amino acid sequence VH as shown in any one of SEQ ID NO: 7, 17, 27 and 37, and the light chain contains the amino acid sequence VL as shown in any one of SEQ ID NO: 8, 18, 28 and 38; and

[0136] c) An antibody comprising the following heavy and light chains, wherein the heavy chain comprises HCDR1 with an amino acid sequence as shown in any one of SEQ ID NO: 1, 11, 21, and 31, HCDR2 with an amino acid sequence as shown in any one of SEQ ID NO: 2, 12, 22, and 32, and HCDR3 with an amino acid sequence as shown in any one of SEQ ID NO: 3, 13, 23, and 33, and the light chain comprises LCDR1 with an amino acid sequence as shown in any one of SEQ ID NO: 4, 14, 24, and 34, LCDR2 with an amino acid sequence as shown in any one of SEQ ID NO: 5, 15, 25, and 35, and LCDR3 with an amino acid sequence as shown in any one of SEQ ID NO: 6, 16, 26, and 36.

[0137] In some embodiments, the antibody is selected from chimeric antibodies, humanized antibodies, and fully human antibodies.

[0138] In some embodiments, the antigen-binding fragment is selected from Fab, Fv, scFv, Fab', and (Fab')2.

[0139] In some embodiments, the antibody that specifically binds to PD-1 and / or PD-L1 comprises:

[0140] Nivolumab's HCDR1-3 and LCDR1-3,

[0141] pembrolizumab's HCDR1-3 and LCDR1-3,

[0142] BMS-936559's HCDR1-3 and LCDR1-3;

[0143] MPDL3280A's HCDR1-3 and LCDR1-3;

[0144] MEDI4736's HCDR1-3 and LCDR1-3; or

[0145] MSB0010718C's HCDR1-3 and LCDR1-3.

[0146] In some embodiments, the antibody that specifically binds to PD-1 and / or PD-L1 comprises:

[0147] Nivolumab's VH and VL,

[0148] Pembrolizumab in VH and VL,

[0149] BMS-936559's VH and VL;

[0150] VH and VL of MPDL3280A;

[0151] MEDI4736's VH and VL; or

[0152] VH and VL in MSB0010718C.

[0153] In some embodiments, the antibody that specifically binds to PD-1 and / or PD-L1 is selected from: nivolumab, pembrolizumab, BMS-936559, MPDL3280A, MEDI4736, AMP-224 and MSB0010718C.

[0154] In some embodiments, the ratio of the effective amount of the PDE4 selective inhibitor to the effective amount of the immune checkpoint inhibitor is about 9:1 to about 1:4 (mass ratio).

[0155] In some embodiments, the PDE4 selective inhibitor and the immune checkpoint inhibitor are each contained in separate containers.

[0156] In some embodiments, the drug combination comprises a first formulation and a second formulation, the first formulation comprising the immune checkpoint inhibitor and a pharmaceutically acceptable first carrier, and the second formulation comprising the PDE4 selective inhibitor and a pharmaceutically acceptable second carrier.

[0157] In some embodiments, the PDE4 selective inhibitor is present in the second formulation at a concentration of about 20% to about 90% (w / w).

[0158] In some embodiments, the immune checkpoint inhibitor is present in the first formulation at a concentration of about 10% to about 80% (w / w).

[0159] In some embodiments, it comprises a pharmaceutical composition, wherein the pharmaceutical composition comprises the PDE4 selective inhibitor and the immune checkpoint inhibitor.

[0160] In some embodiments, the PDE4 selective inhibitor is present in the pharmaceutical composition at a concentration of about 20% to about 90% (w / w).

[0161] In some embodiments, the immune checkpoint inhibitor is present in the pharmaceutical composition at a concentration of about 10% to about 80% (w / w).

[0162] On the other hand, this application also provides a reagent kit that includes the drug combination described in this application.

[0163] The drug combination or kit described in this application is used for the prevention and / or treatment of tumors.

[0164] According to the drug combination or kit in this application, the tumor includes solid tumors, hematologic malignancies, and / or lymphomas.

[0165] According to the drug combination or kit in this application, the tumor includes colon cancer, breast cancer, and / or melanoma.

[0166] According to the drug combination or kit in this application, the tumor includes metastatic tumors.

[0167] According to the drug combination or kit in this application, the tumor includes liver metastases.

[0168] According to the drug combination or kit in this application, the tumor includes colon cancer with liver metastases.

[0169] On the other hand, this application also provides a selective PDE4 inhibitor for the prevention and / or treatment of tumors.

[0170] According to the PDE4 selective inhibitor in this application, it is used in combination with the immune checkpoint inhibitor in this application for the prevention and / or treatment of tumors.

[0171] According to the PDE4 selective inhibitor in this application, wherein the PDE4 selective inhibitor is the PDE4 selective inhibitor in this application.

[0172] According to the PDE4 selective inhibitor in this application, the tumor includes solid tumors, hematologic malignancies, and / or lymphomas.

[0173] According to the PDE4 selective inhibitor in this application, the tumor includes colon cancer, breast cancer, and / or melanoma.

[0174] According to the PDE4 selective inhibitor in this application, the tumor includes metastatic tumors.

[0175] According to the PDE4 selective inhibitor in this application, the tumor includes liver metastases.

[0176] According to the PDE4 selective inhibitor in this application, the tumor includes colon cancer with liver metastases.

[0177] On the other hand, this application also provides a method for preventing and / or treating tumors, comprising administering an effective amount of the PDE4 selective inhibitor of this application to a subject in need.

[0178] The method according to this application also includes administering an effective amount of the immune checkpoint inhibitor of this application to the subject.

[0179] According to the method in this application, the PDE4 selective inhibitor and the immune checkpoint inhibitor are administered simultaneously or sequentially.

[0180] According to the method in this application, the tumor includes solid tumors, hematologic malignancies, and / or lymphomas.

[0181] According to the method in this application, the tumor includes colon cancer, breast cancer, and / or melanoma.

[0182] According to the method in this application, the tumor includes metastatic tumors.

[0183] According to the method in this application, the tumor includes liver metastases.

[0184] According to the method in this application, the tumor includes colon cancer with liver metastases.

[0185] On the other hand, this application also provides the use of a PDE4 selective inhibitor in the preparation of a medicament for the prevention and / or treatment of tumors.

[0186] On the other hand, this application also provides the use of a PDE4 selective inhibitor and an immune checkpoint inhibitor in the preparation of a medicament for the prevention and / or treatment of tumors.

[0187] According to the intended use in this application, the PDE4 selective inhibitor is the PDE4 selective inhibitor in this application.

[0188] According to the intended use in this application, the immune checkpoint inhibitor is the immune checkpoint inhibitor described in this application.

[0189] According to the intended use in this application, the tumor includes solid tumors, hematologic malignancies, and / or lymphomas.

[0190] According to the intended use in this application, the tumor includes colon cancer, breast cancer, and / or melanoma.

[0191] According to the intended use in this application, the tumor includes metastatic tumors.

[0192] According to the intended use in this application, the tumor includes tumors that have metastasized to the liver.

[0193] According to the intended use in this application, the tumor includes colon cancer with liver metastases.

[0194] Other aspects and advantages of this application will readily be apparent to those skilled in the art from the detailed description below. Only exemplary embodiments of this application are shown and described in the following detailed description. As will be appreciated by those skilled in the art, the content of this application enables them to make modifications to the disclosed specific embodiments without departing from the spirit and scope of the invention to which this application pertains. Accordingly, the descriptions in the accompanying drawings and specification of this application are merely exemplary and not restrictive. Attached Figure Description

[0195] The specific features of the invention involved in this application are shown in the appended claims. The features and advantages of the invention can be better understood by referring to the exemplary embodiments and drawings described in detail below. A brief description of the drawings is as follows:

[0196] Figure 1 A and 1B show the effect of the PDE4 selective inhibitor described in this application on inhibiting tumor cell metastasis.

[0197] Figure 2 A, 2B, and 2C show the in vivo effects of the combination therapy of the PDE4 selective inhibitor and the immune checkpoint inhibitor described in this application for colorectal cancer.

[0198] like Figure 3 The results show that roflumilast inhibits metastasis. For example... Figure 4 The results shown are from BPN14770 inhibiting metastasis.

[0199] like Figure 5 The results shown are those of GSK256066 inhibiting metastasis. For example... Figure 6 The results shown are from the inhibition of metastasis by cyclophosphamide. For example... Figure 7 The result shown is that dipyridamole inhibits metastasis. For example... Figure 8 The results show the inhibitory effect of roflumilast on tumor metastasis.

[0200] like Figure 9 As shown, the tumor suppression effect of combining PDE4 inhibitors with immune checkpoint inhibitors.

[0201] like Figure 10 As shown, PDE4 knockout inhibits tumor metastasis. Detailed Implementation

[0202] The following specific embodiments illustrate the implementation of the invention. Those skilled in the art can easily understand other advantages and effects of the invention from the content disclosed in this specification.

[0203] Terminology Definition

[0204] In this application, the term "antagonist" generally refers to any molecule described herein, such as a protein, that partially or completely blocks, inhibits, or neutralizes it. For example, the molecules of this application include, but are not limited to, CTLA-4, PD-1, PD-L1, PD-L2, LAG-3, TIM-3, galactoglobulin 9, CEACAM-1, BTLA, CD69, galactoglobulin-1, TIGIT, CD113, GPR56, VISTA, 2B4, CD48, GARP, PD1H, LAIR1, TIM-1, and / or TIM-4. Suitable antagonist molecules particularly include antagonist antibodies or antibody fragments, fragments or amino acid sequence variants of the molecules of this application, peptides, antisense oligonucleotides, small organic molecules, etc. Methods for identifying antagonists of the molecules of this application include contacting cells expressing the molecules of this application with candidate antagonist molecules and detecting detectable changes in one or more biological activities associated with the molecules of this application. Antagonists can also be peptides prepared by rational design or through phage display technology. When this peptide is antagonized by itself, it can also fuse to cytotoxic agents to increase or enhance the peptide's antagonistic properties.

[0205] In this application, the term "variant" generally refers to a molecule that can include amino acid modifications (e.g., group substitutions, etc.) or insertions, substitutions, and / or deletions of one or more amino acids in the original protein sequence while retaining the function of the original sequence. For example, the variant may have better biological activity (function) than the original sequence. For example, the retention does not have to be complete. For example, the variant may substantially retain the function of the original sequence, for example, retaining at least 50%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% of the function of the original sequence. For example, the amino acid sequence of the variant may be at least 50%, 70%, 75%, or 80% different from the original amino acid sequence.

[0206] 85%, 90%, 95%, 96%, 97%, 98%, or 99% are the same.

[0207] In this application, the term "combination" generally refers to the use of more than one treatment. The use of the term "combination" does not limit the order in which treatments are administered to a subject. The first treatment may be administered before (e.g., 1 minute, 5 minutes, 15 minutes, 30 minutes, 45 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 12 hours, 24 hours, 48 ​​hours, 72 hours, 96 hours, 1 week, 2 weeks, 3 weeks, 4 weeks, 5 weeks, 6 weeks, 8 weeks, or 12 weeks before), concurrently with, or after (e.g., 1 minute, 5 minutes, 15 minutes, 30 minutes, 45 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 12 hours, 24 hours, 48 ​​hours, 72 hours, 96 hours, 1 week, 2 weeks, 3 weeks, 4 weeks, 5 weeks, 6 weeks, 8 weeks, or 12 weeks after) the second treatment. Any additional treatment may be administered in any order with other additional treatments. For example, the PDE4 selective inhibitor of this application can be administered in combination with one or more substances, such as immune checkpoint inhibitors.

[0208] In this application, the term "immune checkpoint inhibitor" generally refers to a molecule that, in whole or in part, reduces, inhibits, interferes with, or modulates one or more checkpoint proteins. Checkpoint proteins can regulate T cell activation or function. A variety of checkpoint proteins are known to include, for example, CTLA-4 and its ligands CD80 and CD86; and PD1 and its ligands PDL1 and PDL2. These proteins can be responsible for co-stimulatory or inhibitory interactions in T cell responses. Immune checkpoint proteins can regulate and maintain self-tolerance and the duration and magnitude of physiological immune responses. Immune checkpoint inhibitors may include antibodies or antibody-derived peptides.

[0209] In this application, the term "container" generally refers to any vessel or device suitable for holding a medicine. For example, medicine boxes, medicine bottles, medicine bags, blister packs, tubes, syringes, etc.

[0210] In this application, the term "administration" generally refers to the introduction of the drug combination into the body of a subject by any route of introduction or delivery. Any method known to those skilled in the art for contacting cells, organs, or tissues with the drug combination may be employed, including but not limited to intra-arterial, intranasal, intraperitoneal, intravenous, intramuscular, subcutaneous transdermal, or oral administration. The daily dose may be divided into one, two, or more doses in suitable forms to be administered at one, two, or more times during a certain time period.

[0211] In this application, the term "subject" generally refers to a human or non-human animal, including but not limited to cats, dogs, horses, pigs, cows, sheep, rabbits, mice, rats, or monkeys.

[0212] In this application, the term "sequential administration" generally refers to a time interval greater than 1 hour between the administration of the first active ingredient and the administration of the last active ingredient to a subject when the active ingredients of a drug combination are administered. For example, the active ingredients of the drug combination may include the PDE4 selective inhibitor and / or immune checkpoint inhibitor of this application.

[0213] In this application, the term "simultaneously" administering the drug combination to the subject generally means that the active ingredients of the drug combination are administered to the subject simultaneously in the form of a composition / mixture, or that when the active ingredients of the drug combination are administered to the subject, the time interval between the administration of the first active ingredient and the administration of the last active ingredient does not exceed 1 hour. For example, the active ingredients of the drug combination may include the PDE4 selective inhibitor and / or immune checkpoint inhibitor of this application.

[0214] In this application, the term "pharmaceutical combination" generally refers to a combination containing at least two active ingredients / therapeutic agents. For example, each active ingredient / therapeutic agent may be prepared as an independent formulation (solid, liquid, gel, etc.); for example, each active ingredient / therapeutic agent may be present in different containers; and may be formulated simultaneously or separately with suitable carriers to form a desired formulation when needed; for example, each active ingredient / therapeutic agent may be from different sources (e.g., prepared, manufactured, or sold by different vendors); for example, each active ingredient / therapeutic agent may be mixed to form a pharmaceutical composition.

[0215] In this application, the term "pharmaceutical composition" generally refers to a mixture containing at least two active ingredients that are administered to a subject to treat a specific disease or condition affecting that individual. It allows the active ingredients to be in an effective form and does not contain any additional components that would have unacceptable toxicity to the subject to whom the composition is to be administered. Such a composition may be sterile and may contain a pharmaceutically acceptable carrier.

[0216] In this application, the terms "effective amount" or "effective dose" generally refer to an amount sufficient to achieve or at least partially achieve the desired effect. A "therapeutic effective amount" or "therapeutic effective dose" of a drug or therapeutic agent generally refers to any amount of drug that, when used alone or in combination with another therapeutic agent, promotes disease remission (proven by a reduction in the severity of disease symptoms, an increase in the frequency and duration of asymptomatic periods of the disease, or prevention of damage or disability due to the disease). A "preventive effective amount" or "preventive effective dose" of a drug generally refers to an amount of drug that, when administered alone or in combination with another therapeutic agent to a subject at risk of disease development or relapse, inhibits the development or relapse of the disease. The ability of a therapeutic agent or preventive agent to promote disease remission or inhibit the development or relapse of the disease can be assessed using a variety of methods known to those skilled in the art, such as in human subjects during clinical trials, predicting efficacy in humans in animal model systems, or by determining the activity of the agent in an in vitro assay.

[0217] In this application, the term "carrier" generally refers to any substance other than the active ingredient. For example, the "carrier" in this application may include a pharmaceutically acceptable carrier but may not include a vector for inserting DNA fragments. Examples include pharmaceutically acceptable substances, compositions, or mediators involved in carrying or transporting chemical reagents. Examples include buffers, surfactants, stabilizers, preservatives, absorption enhancers for improving bioavailability, liquid or solid fillers, diluents, excipients, solvents, encapsulation materials, and / or other conventional solubilizers or dispersants. Each carrier must be "acceptable" in the sense of compatibility with the other components of the formulation and must not cause harm to the patient. For example, in this application, a suitable carrier is selected based on the form in which the active ingredient (e.g., a PDE4 selective inhibitor or an immune checkpoint inhibitor) exists (as a composition or as a separate formulation). For example, when the different active ingredients exist independently, they can be combined with suitable carriers (i.e., the first, second, or third carrier described in this application) to form an administration-appropriate formulation.

[0218] In this application, the term "formulation," also known as a pharmaceutical preparation, generally refers to a drug that is prepared in accordance with certain dosage form requirements to meet therapeutic or preventative needs and can be provided to a subject. For example, a formulation may contain an active ingredient and a carrier.

[0219] In this application, the term "prevention" generally refers to an intervention taken on a healthy subject before the onset of symptoms and / or the appearance of a disease, in order to prevent the occurrence of a disease or condition. It may also include the prophylactic application of a combination to a patient in the pre-treatment stage of an allergic disease to be treated. "Prevention" does not require the complete elimination of the likelihood of the disease or condition occurring; for example, "prevention" generally means a reduction in the likelihood or severity of the disease or condition occurring in the presence of said application combination.

[0220] In this application, the term "treatment" generally refers to a clinical intervention used to alter the natural processes of an individual or cell in a clinicopathological process. It may include improving disease status, eliminating lesions, or improving prognosis.

[0221] In this application, the term "tumor" generally refers to a growth or solid lesion formed by abnormal cell growth. In this application, a tumor can be a solid tumor or a non-solid tumor. For example, a tangible mass that can be felt through clinical examination such as X-ray, CT scan, ultrasound, or palpation can be called a solid tumor, while a tumor that cannot be seen or felt by X-ray, CT scan, ultrasound, or palpation, such as leukemia, can be called a non-solid tumor.

[0222] In this application, the term "metastatic tumor" generally refers to a tumor that has spread from its primary site to other locations in the body. Tumor cells can detach from the primary tumor, infiltrate the lymphatic and blood vessels, circulate via the bloodstream, and grow in distant lesions (metastases) in normal tissues elsewhere in the body. Metastasis can be local or distant. Metastasis can be a continuous process, depending on whether tumor cells detach from the primary tumor, spread via the bloodstream, and stop at a distant site. At the new site, the cell establishes a blood supply and can grow to form a life-threatening mass. Both stimulatory and inhibitory molecular pathways within the tumor cells can modulate this behavior, and the interaction between tumor cells and host cells in distant sites can also be important.

[0223] In this application, the term "CDR," also known as "complementarity-determining region," generally refers to a region within the variable structural domain of an antibody whose sequence is highly variable and / or forms a structurally defining loop. Typically, antibodies comprise six CDRs: three in the VH (HCDR1, HCDR2, HCDR3) and three in the VL (LCDR1, LCDR2, LCDR3). For example, naturally occurring camel antibodies composed solely of heavy chains can function normally and stably even in the absence of light chains. See, for example, Hamers-Casterman et al., Nature 363:446-448 (1993); Sheriff et al., Nature Struct. Biol. 3:733-736 (1996). Antibody CDRs can be determined using various coding systems, such as CCG, Kabat, Chothia, IMGT, and a combination of Kabat / Chothia. These coding systems are known in the art, and for example, see www.bioinf.org.uk / abs / index.html#kabatnum. For example, the amino acid sequence number of the antigen-binding protein can be in accordance with the IMGT numbering scheme (IMGT, the international ImMunoGeneTics information system @imgt.cines.fr; http: / / imgt.cines.fr; Lefranc et al., 1999, Nucleic Acids Res. 27:209-212; Ruiz et al., 2000, Nucleic Acids Res. 28:219-221; Lefranc et al., 2001, Nucleic Acids Res. 29:207-209; Lefranc et al., 2003, Nucleic Acids Res. 31:307-310; Lefranc et al., 2005, DevComp Immunol 29:185-203). For example, the CDR of the antigen-binding protein can be determined according to the Kabat numbering system (see, for example, Kabat EA & Wu TT (1971) Ann NY Acad Sci 190:382-391 and Kabat EA et al., (1991) Sequences of Proteins of Immunological Interest, Fifth Edition, USD Department of Health and Human Services, NIH Publication No. 91-3242).

[0224] In this application, the term "antibody" generally refers to an immunoglobulin or a fragment thereof or a derivative thereof, encompassing any polypeptide that includes an antigen-binding site, whether it is produced in vitro or in vivo. This term includes, but is not limited to, polyclonal, monoclonal, single-specific, multi-specific, non-specific, humanized, single-chain, chimeric, synthetic, recombinant, hybrid, mutated, and transplanted antibodies. Unless otherwise modified by the term "complete," such as in "complete antibody," for the purposes of this application, the term "antibody" also includes antibody fragments such as Fab, F(ab')2, Fv, scFv, Fd, dAb, and other antibody fragments that maintain antigen-binding function (e.g., specific binding to PD-L1). Typically, such fragments should include an antigen-binding domain. The basic 4-chain antibody unit is a heterotetrameric glycoprotein composed of two identical light (L) chains and two identical heavy (H) chains. IgM antibodies consist of five basic heterotetrameric units and a polypeptide chain called the J chain, containing 10 antigen-binding sites. IgA antibodies consist of 2-5 basic tetrameric units that can polymerize with the J chain to form multivalent combinations. For IgG, a tetrameric unit is typically about 150,000 Daltons. Each L chain is linked to an H chain by a covalent disulfide bond, and two H chains are linked to each other by one or more disulfide bonds depending on the H chain isoform. Each H and L chain also has regularly spaced intrachain disulfide bridging bonds. Each H chain has a variable domain (VH) at its N-terminus, followed by three constant domains (CH) for α and γ chains, and four CH domains for μ and ε isoforms. Each L chain has a variable domain (VL) at its N-terminus and a constant domain at its other end. VL corresponds to VH, and CL corresponds to the first constant domain (CH1) of the heavy chain. Specific amino acid residues are thought to form interfaces between the variable domains of the light and heavy chains. VH and VL pair together to form a single antigen-binding site. For the structure and properties of different classes of antibodies, see, for example, Basic and Clinical Immunology, 8th Edition, Daniel P. Sties, Abba I. Terr and Tristram G. Parsolw (eds), Appleton & Lange, Norwalk, Conn., 1994, p. 71 and Chapter 6. L chains from any vertebrate species can be classified into one of two distinct types, called κ and λ, based on the amino acid sequence of their constant domains. Immunoglobulins can be classified into different classes or isotypes based on the amino acid sequence of their heavy chain (CH) constant domains. Currently, there are five classes of immunoglobulins: IgA, IgD, IgE, IgG, and IgM, with heavy chains named α, δ, ε, γ, and μ, respectively.

[0225] In this application, the term "antigen-binding fragment" generally refers to one or more polypeptide fragments having the ability to specifically bind to an antigen (e.g., PD-L1). In this application, the antigen-binding fragment may include Fab, Fab', F(ab)2, Fv fragments, F(ab')2, scFv, di-scFv, and / or dAb.

[0226] In this application, the term "variable region" generally refers to a region in which certain segments of the variable domain may differ significantly in sequence between antibodies. A "variable region" in the light chain may contain the light chain variable region (VL); a "variable region" in the heavy chain may contain the heavy chain variable region (VH). The variable domain mediates antigen binding and determines the specificity of a particular antibody for its specific antigen. However, variability is not uniformly distributed across the entire variable domain. It is typically concentrated in three segments within the light and heavy chain variable domains, known as hypervariable regions (CDRs or HVRs). The more highly conserved portions of the variable domain are called framework regions (FRs). The variable domains of the native heavy and light chains each contain four FR regions, most of which adopt a β-sheet configuration linked by three CDRs forming a ring link, and in some cases, forming part of a β-sheet structure. CDRs in each chain are held together closely by the FR region, and CDRs from the other chain together promote the formation of the antigen-binding site of the antibody (see Kabat et al, Sequences of Immunological Interest, Fifth Edition, National Institute of Health, Bethesda, Md. (1991)).

[0227] In this application, the term "Fab" generally refers to the antigen-binding fragment of an antibody. As described above, an intact antibody can be digested using papain. After digestion with papain, the antibody produces two identical antigen-binding fragments, namely the "Fab" fragment, and a residual "Fc" fragment (i.e., the Fc region, as above). The Fab fragment may consist of a complete L chain with a variable region of a heavy chain and a first constant region (CH1) of the H chain (VH).

[0228] In this application, the term "Fab'" or "Fab' fragment" generally refers to a monovalent antigen-binding fragment of a human monoclonal antibody, which is slightly larger than the Fab fragment. For example, the Fab' fragment may include all light chains, all heavy chain variable regions, and all or part of the first and second constant regions of the heavy chain. For example, the Fab' fragment may also include part or all of the 220-330 amino acid residues of the heavy chain.

[0229] In this application, the term "(Fab')2" generally refers to an antibody fragment produced by digesting an intact antibody with pepsin. The F(ab')2 fragment contains two Fab fragments held together by disulfide bonds and a partial hinge region. The F(ab')2 fragment exhibits bivalent antigen-binding activity and is capable of cross-linking antigens.

[0230] In this application, the term "Fv" or "Fv fragment" generally refers to a monovalent antigen-binding fragment of a human monoclonal antibody, comprising all or part of the heavy chain variable region and light chain variable region, and lacking the heavy chain constant region and light chain constant region. The heavy chain variable region and light chain variable region include, for example, CDRs. For example, an Fv fragment comprises all or part of the amino-terminal variable region of about 110 amino acids of the heavy and light chains.

[0231] In this application, the term "scFv" generally refers to a fusion protein comprising at least one antibody fragment including a variable region comprising a light chain and at least one antibody fragment including a variable region comprising a heavy chain, wherein the light and heavy chain variable regions are adjacent (e.g., via a synthetic linker such as a short, flexible peptide linker) and are capable of being expressed as a single-chain polypeptide, and wherein the scFv retains the specificity of the intact antibody from which it is derived. Unless otherwise specified, as used in this application, the scFv may have the VL and VH variable regions in any order (e.g., relative to the N-terminus and C-terminus of the polypeptide), and the scFv may comprise VL-linker-VH or may comprise VH-linker-VL.

[0232] In this application, the term “dAb” generally refers to an antigen-binding fragment having a VH domain, a VL domain, or having a VH domain or a VL domain, for example, Ward et al. (Nature, 1989 Oct 12; 341(6242): 544-6), Holt et al., Trends Biotechnol., 2003, 21(11): 484-490; and other published patent applications such as WO2006030220A1, WO2006003388A2 and Domantis Ltd.

[0233] In this application, the term "monoclonal antibody" generally refers to an antibody molecule preparation consisting of a single molecule. Monoclonal antibodies typically exhibit high specificity against a single antigenic site. Moreover, unlike conventional polyclonal antibody preparations (which usually contain different antibodies targeting different determinants), each monoclonal antibody targets a single determinant on the antigen. In addition to their specificity, monoclonal antibodies have the advantage that they can be synthesized through hybridoma culture without contamination by other immunoglobulins. The modifier "monoclonal" indicates the characteristic of antibodies obtained from a substantially homogeneous group of antibodies and is not to be interpreted as requiring the production of antibodies through any particular method. For example, the monoclonal antibodies used in this application can be prepared in hybridoma cells or through recombinant DNA methods.

[0234] In this application, the term "chimeric antibody" generally refers to an antibody in which the variable region is derived from one species and the constant region is derived from another species. Typically, the variable region is derived from an antibody from a laboratory animal such as a rodent ("parental antibody") and the constant region is derived from a human antibody, such that the resulting chimeric antibody is less likely to elicit an adverse immune response in human individuals compared to parental (e.g., mouse-derived) antibodies.

[0235] In this application, the term "humanized antibody" generally refers to an antibody in which some or all of the amino acids outside the CDR region of a non-human antibody (e.g., a mouse antibody) are replaced by corresponding amino acids derived from human immunoglobulins. Small additions, deletions, insertions, substitutions, or modifications of amino acids in the CDR region are also permissible, as long as they retain the antibody's ability to bind to a specific antigen. Humanized antibodies may optionally contain at least a portion of the constant region of human immunoglobulins. "Humanized antibodies" retain antigen specificity similar to the original antibody. The "humanized" form of a non-human (e.g., mouse) antibody may minimally contain a chimeric antibody with a sequence derived from a non-human immunoglobulin. In some cases, CDR region residues in a human immunoglobulin (receptor antibody) may be replaced with CDR region residues from a non-human species (donor antibody) (such as a mouse, rat, rabbit, or non-human primate) having the desired properties, affinity, and / or capabilities. In some cases, FR region residues in a human immunoglobulin may be replaced with corresponding non-human residues. Furthermore, humanized antibodies may contain amino acid modifications not found in receptor antibodies or in donor antibodies. These modifications can be made to further improve antibody performance, such as binding affinity.

[0236] In this application, the term "fully human antibody" generally refers to an antibody that contains only the protein sequence of human immunoglobulins. If it is produced in mice, in mouse cells, or in hybridomas derived from mouse cells, then a fully human antibody may contain mouse glycans. Similarly, "mouse antibody" or "rat antibody" refers to an antibody that contains only mouse or rat immunoglobulin sequences, respectively. Fully human antibodies can be generated in humans or in transgenic animals with germline sequences of human immunoglobulins by phage display or other molecular biology methods. Exemplary techniques that can be used to manufacture antibodies are described in U.S. Patents: 6,150,584, 6,458,592, and 6,420,140. Other techniques, such as the use of libraries, are known in the art.

[0237] In this application, the term "PD-1" or "PD1" generally refers to Programmable Cell Death Protein 1, a type I membrane protein of 288 amino acids, first described in 1992 (Ishida et al., EMBO J., 11(1992), 3887-3895). PD-1 is a member of the expanded family of CD28 / CTLA-4 T cell regulators and has two ligands, PD-L1 (B7-H1,

[0238] PD-1 (CD274) and PD-L2 (B7-DC, CD273) are proteins whose structure includes an extracellular IgV domain followed by a transmembrane region and an intracellular tail. The intracellular tail contains two phosphorylation sites located in the immunoreceptor's tyrosine-based inhibitory motif and the immunoreceptor's tyrosine-based switching motif, suggesting that PD-1 negatively regulates TCR signaling. This is consistent with the binding of SHP-1 and SHP-2 phosphatases to the cytoplasmic tail of PD-1 after ligand binding. Although PD-1 is not expressed on naive T cells, it is upregulated after T cell receptor (TCR)-mediated activation and has been observed on both activated and depleted T cells (Agata et al., Int. Immunology 8 (1996), 765-772). These depleted T cells exhibit a dysfunctional phenotype and are unable to respond appropriately. Although PD-1 has a relatively broad expression pattern, its most important role is likely as a co-inhibitory receptor on T cells (Chinai et al., Trends in Pharmacological Sciences 36 (2015), 587-595). Current therapeutic approaches therefore focus on blocking the interaction between PD-1 and its ligands to enhance T cell responses. The terms “programmed cell death 1,” “programmed cell death 1,” “protein PD-1,” “PD-1,” “PD1,” “PDCD1,” “hPD-1,” and “hPD-I” are used interchangeably and include variants, isotypes, species homologs, and analogs that share at least one epitope with PD-1. The amino acid sequence of human PD-1 can be found in UniProt (www.uniprot.org) accession number Q15116.

[0239] In this application, the term “PD-L1” or “PDL1” generally refers to programmed cell death ligand 1, also known as B7 homolog 1, B7-H1, differentiation cluster 274, (3)274, or CD274, which downregulates T cell activation and cytokine secretion upon binding to PD-1. “PD-L1” includes any naturally occurring PD-L1 of any vertebrate origin, including mammals such as primates (e.g., humans and cynomolgus monkeys) and rodents (e.g., mice and rats). The term encompasses “full-length”, unprocessed PD-L1, and any form of PD-L1 produced by cellular processing. PD-L1 may exist as a transmembrane protein or as a soluble protein. “PD-L1” includes complete PD-L1 and fragments thereof, as well as functional variants, isoforms, species homologs, derivatives, analogs of PD-L1, and analogs having at least one epitope co-occurring with PD-L1. The basic structure of PD-L1 comprises four domains: an extracellular Ig-like V-type domain and an Ig-like C2-type domain, a transmembrane domain, and a cytoplasmic domain. An exemplary human PD-L1 amino acid sequence can be found in the NCBI accession number.

[0240] Find it under NP_001254653 or UniProt login number Q9NZQ7.

[0241] In this application, the terms “pembrolizumab” or “pembrolizumab” generally refer to a PD-1 monoclonal antibody. Descriptions of pembrolizumab can be found, for example, in U.S. Patent Nos. 8,354,509 and 8,900,587.

[0242] In this application, the term "AMP-224" generally refers to an immune checkpoint inhibitor. For example, it could be a B7-DCFc fusion protein. A description of AMP-224 can be found in U.S. Publication No. 2013 / 0017199A.

[0243] In this application, the term "BMS-936559" generally refers to an immune checkpoint inhibitor. For example, it can be an anti-PD-L1 antibody, and BMS-936559 can also be referred to as 12A4 or MDX-1105. A description of BMS-936559 can be found in U.S. Patent Nos. 7,943,743 or WO2013 / 173223A1.

[0244] In this application, the term "MEDI4736" generally refers to an immune checkpoint inhibitor. For example, it could be an anti-PD-L1 antibody, and MEDI4736 can also be referred to as Durvalumab. A description of MEDI4736 can be found in Khleif (2013) In: Proceedings from the European Cancer Congress 2013; 27 September – 1 October 2013; Amsterdam, The Netherlands.

[0245] In this application, the term "MPDL3280A" generally refers to an immune checkpoint inhibitor. For example, it can be an anti-PD-L1 antibody, and MPDL3280A can also be referred to as RG7446 or atezolizumab. A description of MPDL3280A can be found in Herbst et al. (2013) J Clin Oncol 31(suppl):3000. Abstract. or U.S. Patent No. 8,217,149.

[0246] In this application, the term "MSB0010718C" generally refers to an immune checkpoint inhibitor. For example, it could be an anti-PD-L1 antibody, and MSB0010718C could also be referred to as Bavencio or Avelumab. A description of MSB0010718C can be found in US 2014 / 0341917A1.

[0247] In this application, the term "PDE4" generally refers to a member of the PDE4 subfamily or a functional variant thereof within the phosphodiesterase (PDE) family, which is capable of disrupting phosphodiester bonds. Phosphodiesterases (PDEs) function to hydrolyze intracellular second messengers (cAMP, cyclic adenosine monophosphate or cGMP, cyclic guanosine monophosphate), degrading intracellular cAMP or cGMP and thus terminating the biochemical processes mediated by these second messengers. PDEs are a large, multi-gene family that, in mammals, can be divided into 12 families, PDE1-PDE12, based on 1) amino acid sequence, 2) substrate specificity, 3) regulatory properties, 4) pharmacological properties, and 5) tissue distribution. The PDE nomenclature uses Arabic numerals to represent PDE families, followed by a capital letter indicating the gene within that family, and a second Arabic numeral indicating a splice variant from a single gene (e.g., PDE1C3: family 1, gene C, splice variant 3). Different PDEs within the same family may exhibit significant differences in amino acid sequences, but they are functionally related. PDEs have different substrate specificities. For example, PDE4 is a cAMP-selective hydrolase. In humans, PDE4 can be divided into four subtypes: PDE4A, 4B, 4C, and 4D.

[0248] In this application, the term "PDE4 selective inhibitors" generally refers to inhibitors that selectively act on the PDE4 subfamily within the PDE family. Among all members of the PDE family, they primarily inhibit PDE4, while having little to no inhibitory effect on other PDE family members. In other words, PDE4 selective inhibitors are defined relative to other members of the PDE family, but the possibility of inhibitory effects on other molecules outside the PDE family cannot be excluded. PDE4 selective inhibitors can inhibit one or more subtypes of the PDE4 family.

[0249] In this application, the term "PDE5 selective inhibitors" generally refers to inhibitors that selectively act on the PDE5 subfamily within the PDE family. For example, PDE5 selective inhibitors may be Tadalafil (CAS#:171596-29-5), Sildenafil citrate (CAS#:171599-83-0), or Kuraridine (CAS#:34981-25-4), etc.

[0250] In this application, the term "alkoxy" generally refers to an -OR group, where R may be an optionally substituted alkyl group.

[0251] In this application, the term "alkyl" generally refers to a straight-chain and branched saturated hydrocarbon group. Non-limiting examples may include methyl, ethyl, and straight-chain and branched propyl and butyl groups.

[0252] In this application, the term "halogen" refers to halogens of Group VIIA of the periodic table, such as F, Cl, Br, and I.

[0253] In this application, the term "amino" generally refers to the -NH group. One or both hydrogen atoms may optionally be substituted, for example, with an alkyl group, a substituted alkyl group, a cycloalkyl group, an aryl group, or a heteroaryl group.

[0254] In this application, as those skilled in the art will know, terms such as "alkyl," "alkenyl," and "cycloalkyl" may be preceded by an identifier indicating the number of atoms present in the group under specific conditions, for example, C1-C4 alkyl, C3-C7 cycloalkoxy, C1-C4 alkylcarbonylamino, etc., and the subscript number following "C" indicates the number of carbon atoms present in the group. For example, C3 alkyl refers to an alkyl group having three carbon atoms (e.g., n-propyl, isopropyl); C 1-10 In this context, the members of the group can have any number of carbon atoms falling within the range of 1-4.

[0255] In this application, the terms "comprising" or "including" generally mean including the expressly specified features, but do not exclude other elements. In some cases, "comprising" or "including" also covers the meaning of "is" or "consisting of".

[0256] In this application, the term "about" generally refers to a variation within a range of 0.5% to 10% above or below a specified value, such as a variation within a range of 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, or 10% above or below a specified value.

[0257] In this application, as those skilled in the art will know, terms such as "alkyl," "alkenyl," and "cycloalkyl" may be preceded by an identifier indicating the number of atoms present in the group under specific conditions, for example, C1-C4 alkyl, C3-C7 cycloalkoxy, C1-C4 alkylcarbonylamino, etc., and the subscript number after "C" indicates the number of carbon atoms present in the group. For example, C3 alkyl refers to an alkyl group having three carbon atoms (e.g., n-propyl, isopropyl, etc.); C 1-10 In this context, the members of the group can have any number of carbon atoms falling within the range of 1-10. Invention Details

[0259] On the one hand, this application provides a drug combination that may comprise:

[0260] a) An effective dose of an immune checkpoint inhibitor; and

[0261] b) An effective amount of a PDE4 selective inhibitor. For example, the PDE4 selective inhibitor of this application may contain a substance that reduces the expression of the gene encoding PDE4.

[0262] On the other hand, this application also provides the use of immune checkpoint inhibitors and PDE4 selective inhibitors in the preparation of pharmaceuticals, which can be used for the prevention and / or treatment of tumors. For example, the PDE4 selective inhibitor of this application may contain a substance that reduces the expression of the gene encoding PDE4.

[0263] On the other hand, this application also provides the use of a PDE4 selective inhibitor in the preparation of a medicament, which can be used for the prevention and / or treatment of metastatic colorectal cancer. For example, the PDE4 selective inhibitor of this application may contain a substance that reduces the expression of the gene encoding PDE4. Furthermore, this application also provides the use of a PDE4 selective inhibitor in the preparation of a medicament, which can be used for the prevention and / or treatment of metastatic colorectal cancer and / or metastatic breast cancer.

[0264] On the other hand, this application also provides a method for preventing and / or treating tumors, which may include administering the treatment to a subject in need:

[0265] a) An effective dose of immune checkpoint inhibitors; and

[0266] b) An effective amount of a selective PDE4 inhibitor.

[0267] On the other hand, this application also provides a method for preventing and / or treating metastatic colorectal cancer, which may include administering an effective amount of a PDE4 selective inhibitor to a subject in need.

[0268] On the other hand, this application also provides immune checkpoint inhibitors and PDE4 selective inhibitors, which can be used for the prevention and / or treatment of tumors.

[0269] On the other hand, this application also provides a selective PDE4 inhibitor that can be used for the prevention and / or treatment of metastatic colorectal cancer.

[0270] On the other hand, this application also provides a kit that may include the drug combination of this application.

[0271] On the other hand, this application also provides a kit that may include the PDE4 selective inhibitor of this application.

[0272] On the one hand, this application provides a drug combination that may comprise:

[0273] a) An effective dose of an immune checkpoint inhibitor; and

[0274] b) An effective amount of the compound represented by formula I, a pharmaceutically acceptable salt thereof, or an N-oxide of pyridine or a salt thereof:

[0275]

[0276] Wherein, one of R1 and R2 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and the other of R1 and R2 can be a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and

[0277] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino, or C1-C4 alkylcarbonylamino. R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, or amino; R35 can be hydrogen, halogen, amino, or C1-C4 alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0278] On the other hand, this application also provides immune checkpoint inhibitors and pharmaceutically acceptable salts of compounds of Formula I, or N-oxides of pyridine or salts thereof:

[0279]

[0280] Wherein, one of R1 and R2 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and the other of R1 and R2 can be a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and

[0281] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino, or C1-C4 alkylcarbonylamino; R32 can be hydrogen, hydroxyl, halogen, or ammonia. R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxy carbonyl, or amino; R35 can be hydrogen, halogen, amino, or C1-C4 alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen. In the preparation of the pharmaceutical product, the pharmaceutical product of this application can be used for the prevention and / or treatment of tumors.

[0282] On the other hand, this application also provides a pharmaceutically acceptable salt of the compound represented by Formula I, or an N-oxide of pyridine or a salt thereof:

[0283]

[0284] In the preparation of the medicament, the medicament of this application can be used for the prevention and / or treatment of metastatic colon cancer, wherein one of R1 and R2 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy wholly or partially substituted with fluorine, and the other of R1 and R2 can be a C1-C4 alkoxy wholly or partially substituted with fluorine, and

[0285] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino, or C1-C4 alkylcarbonylamino. R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, or amino; R35 can be hydrogen, halogen, amino, or C1-C4 alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0286] On the other hand, this application also provides a method for preventing and / or treating tumors, which may include administering the treatment to a subject in need:

[0287] a) An effective dose of immune checkpoint inhibitors; and

[0288] b) An effective amount of the compound represented by formula I, a pharmaceutically acceptable salt thereof, or an N-oxide of pyridine or a salt thereof:

[0289]

[0290] Wherein, one of R1 and R2 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and the other of R1 and R2 can be a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and

[0291] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino, or C1-C4 alkylcarbonylamino. R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, or amino; R35 can be hydrogen, halogen, amino, or C1-C4 alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0292] On the other hand, this application also provides a method for preventing and / or treating metastatic colorectal cancer, which may include administering to a subject in need an effective amount of a compound of formula I, a pharmaceutically acceptable salt thereof, or an N-oxide of pyridine or a salt thereof:

[0293]

[0294] Wherein, one of R1 and R2 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and the other of R1 and R2 can be a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and

[0295] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino, or C1-C4 alkylcarbonylamino. R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, or amino; R35 can be hydrogen, halogen, amino, or C1-C4 alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0296] On the other hand, this application also provides immune checkpoint inhibitors and pharmaceutically acceptable salts of compounds of Formula I, or N-oxides of pyridine or salts thereof:

[0297]

[0298] It can be used for the prevention and / or treatment of tumors, wherein one of R1 and R2 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy wholly or partially substituted with fluorine, and the other of R1 and R2 can be a C1-C4 alkoxy wholly or partially substituted with fluorine, and

[0299] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1- R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxy, or amino; R35 can be hydrogen, halogen, amino, or C1-C4 alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0300] On the other hand, this application also provides a pharmaceutically acceptable salt of the compound represented by Formula I, or an N-oxide of pyridine or a salt thereof:

[0301]

[0302] It can be used for the prevention and / or treatment of metastatic colorectal cancer, wherein one of R1 and R2 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy wholly or partially substituted with fluorine, and the other of R1 and R2 can be a C1-C4 alkoxy wholly or partially substituted with fluorine, and

[0303] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino, or C1-C4 alkylcarbonylamino. R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, or amino; R35 can be hydrogen, halogen, amino, or C1-C4 alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0304] On the other hand, this application also provides a kit that may include the drug combination of this application.

[0305] On the other hand, this application also provides a kit that may include the compound represented by Formula I of this application, a pharmaceutically acceptable salt thereof, or an N-oxide of pyridine or a salt thereof:

[0306]

[0307] Wherein, one of R1 and R2 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and the other of R1 and R2 can be a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and

[0308] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino, or C1-C4 alkylcarbonylamino. R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, or amino; R35 can be hydrogen, halogen, amino, or C1-C4 alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0309] Drug combination

[0310] In one respect, the drug combination of this application may include: one or more PDE4 selective inhibitors effective in preventing and / or treating the disease.

[0311] In one respect, the pharmaceutical combination of this application may include: a) an effective amount of an immune checkpoint inhibitor for prevention and / or treatment; and b) an effective amount of a selective PDE4 inhibitor for prevention and / or treatment.

[0312] In one aspect, the pharmaceutical composition of this application may comprise: one or more compounds of Formula I in a preventive and / or therapeutically effective amount, a pharmaceutically acceptable salt thereof, or an N-oxide of pyridine or a salt thereof:

[0313]

[0314] Wherein, one of R1 and R2 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and the other of R1 and R2 can be a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and

[0315] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino, or C1-C4 alkylcarbonylamino. R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, or amino; R35 can be hydrogen, halogen, amino, or C1-C4 alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0316] In one aspect, the pharmaceutical combination of this application may comprise: a) a preventive and / or therapeutically effective amount of an immune checkpoint inhibitor; and b) a preventive and / or therapeutically effective amount of one or more compounds of Formula I, a pharmaceutically acceptable salt thereof, or an N-oxide of pyridine or a salt thereof:

[0317]

[0318] Wherein, one of R1 and R2 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and the other of R1 and R2 can be a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and

[0319] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino, or C1-C4 alkylcarbonylamino. R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, or amino; R35 can be hydrogen, halogen, amino, or C1-C4 alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0320] In one aspect, the pharmaceutical composition of this application may comprise: a) an antagonist of one or more proteins selected from the group consisting of: CTLA-4, PD-1, PD-L1, PD-L2, LAG-3, TIM-3, galactoglobulin 9, CEACAM-1, BTLA, CD69, galactoglobulin-1, TIGIT, CD113, GPR56, VISTA, 2B4, CD48, GARP, PD1H, LAIR1, TIM-1, and TIM-4; b) a preventive and / or therapeutically effective amount of one or more compounds of formula I, a pharmaceutically acceptable salt thereof, or an N-oxide of pyridine or a salt thereof.

[0321]

[0322] R1 can be hydrogen, C1-C6-alkoxy, C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0323] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0324] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonylamino. 2 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl or amino, R35 can be hydrogen, halogen, amino or C1-C4-alkyl, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen.

[0325] In one respect, the pharmaceutical composition of this application may comprise: a) an antibody comprising HCDR3 or an antigen-binding fragment thereof, wherein the HCDR3 comprises the amino acid sequence shown in any one of SEQ ID NO: 3, 13, 23 and 33; b) a preventive and / or therapeutically effective amount of one or more compounds of formula I, a pharmaceutically acceptable salt thereof, or an N-oxide of pyridine or a salt thereof.

[0326]

[0327] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0328] R2 can be C3-C5-cycloalkylmethoxy, and

[0329] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0330] In one aspect, the pharmaceutical composition of this application may comprise: a) an antibody comprising a heavy chain and a light chain, wherein the heavy chain comprises HCDR1 with an amino acid sequence as shown in any one of SEQ ID NO: 1, 11, 21, and 31, HCDR2 with an amino acid sequence as shown in any one of SEQ ID NO: 2, 12, 22, and 32, and HCDR3 with an amino acid sequence as shown in any one of SEQ ID NO: 3, 13, 23, and 33, and the light chain comprises LCDR1 with an amino acid sequence as shown in any one of SEQ ID NO: 4, 14, 24, and 34, LCDR2 with an amino acid sequence as shown in any one of SEQ ID NO: 5, 15, 25, and 35, and LCDR3 with an amino acid sequence as shown in any one of SEQ ID NO: 6, 16, 26, and 36; b) a preventive and / or therapeutically effective amount of one or more compounds of formula I, a pharmaceutically acceptable salt thereof, or an N-oxide of pyridine or a salt thereof:

[0331]

[0332] R1 can be a difluoromethoxy group.

[0333] R2 can be cyclopropylmethoxy, and

[0334] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0335] In one aspect, the pharmaceutical composition of this application may comprise: a) an antibody comprising a heavy chain and a light chain, wherein the heavy chain comprises a VH amino acid sequence as shown in any one of SEQ ID NO: 7, 17, 27 and 37, and the light chain comprises a VL amino acid sequence as shown in any one of SEQ ID NO: 8, 18, 28 and 38; b) a preventive and / or therapeutically effective amount of one or more compounds of formula I, a pharmaceutically acceptable salt thereof, or an N-oxide of pyridine or a salt thereof:

[0336]

[0337] R1 can be difluoromethoxy, R2 can be cyclopropylmethoxy, and R3 can be 3,5-dichloropyridin-4-yl.

[0338] In one aspect, the pharmaceutical composition of this application may comprise: a) an antibody selected from the group consisting of nivolumab, pembrolizumab, BMS-936559, MPDL3280A, MEDI4736, AMP-224 and MSB0010718C; b) Roflumilast or a derivative thereof, wherein the Roflumilast derivative of this application comprises Benzanilide, 3-hydroxy-N-(3,5-dichloropyridin-4-yl)-4-methoxybenzamide and / or 4-Methylbenzanilide.

[0339] In this application, the PDE4 selective inhibitor may include a substance capable of at least partially disrupting or inhibiting the activity of one or more members of the PDE4 subfamily.

[0340] For example, members of the PDE4 subfamily may include PDE4A, PDE4B, PDE4C, and / or PDE4D.

[0341] For example, the PDE4 selective inhibitor of this application may include substances that at least partially destroy or inhibit the activity of PDE4A, PDE4B, PDE4C or PDE4D.

[0342] For example, the PDE4 selective inhibitor of this application may include substances that at least partially disrupt or inhibit the activity of PDE4C and PDE4D. For example, the PDE4 selective inhibitor of this application may include substances that at least partially disrupt or inhibit the activity of PDE4B and PDE4C. For example, the PDE4 selective inhibitor of this application may include substances that at least partially disrupt or inhibit the activity of PDE4B and PDE4D. For example, the PDE4 selective inhibitor of this application may include substances that at least partially disrupt or inhibit the activity of PDE4A and PDE4B. For example, the PDE4 selective inhibitor of this application may include substances that at least partially disrupt or inhibit the activity of PDE4A and PDE4C. For example, the PDE4 selective inhibitor of this application may include substances that at least partially disrupt or inhibit the activity of PDE4A and PDE4D.

[0343] For example, the PDE4 selective inhibitor of this application may include substances that at least partially disrupt or inhibit the activity of PDE4A, PDE4B, and PDE4C. For example, the PDE4 selective inhibitor of this application may include substances that at least partially disrupt or inhibit the activity of PDE4A, PDE4C, and PDE4D. For example, the PDE4 selective inhibitor of this application may include substances that at least partially disrupt or inhibit the activity of PDE4A, PDE4B, and PDE4D. For example, the PDE4 selective inhibitor of this application may include substances that at least partially disrupt or inhibit the activity of PDE4B, PDE4C, and PDE4D.

[0344] For example, the PDE4 selective inhibitor of this application may include substances that at least partially destroy or inhibit the activity of PDE4A, PDE4B, PDE4C and PDE4C.

[0345] For example, at least partial disruption or obstruction in this application may include at least 30%, 40%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95% disruption or obstruction.

[0346] For example, the PDE4 selective inhibitor of this application may substantially not disrupt or inhibit the activity of other members of the PDEs family (other than PDE4). For example, substantially not disrupting or inhibiting may include up to 30%, 25%, 20%, 18%, 15%, 13%, 10%, 8%, 5%, 3%, or 1% disruption or inhibition.

[0347] For example, other members of the PDEs family in this application may include members of the PDE1 subfamily, PDE2 subfamily, PDE3 subfamily, PDE5 subfamily, PDE6 subfamily, PDE7 subfamily, PDE8 subfamily, PDE9 subfamily, PDE10 subfamily, PDE11 subfamily, and PDE12 subfamily.

[0348] For example, the activity of this application may include the activity of hydrolyzing cAMP and / or cGMP. For example, the activity of this application in hydrolyzing cAMP and / or cGMP may be determined by any method known to those skilled in the art.

[0349] For example, the PDE4 selective inhibitor of this application may include Apremilast (Otezla);

[0350] For example, the PDE4 selective inhibitor of this application may contain crisaborole (Eucrisa);

[0351] For example, the PDE4 selective inhibitor in this application may include Drotaverine;

[0352] For example, the PDE4 selective inhibitor of this application may contain CC-1088 (CAS#:467421-06-3, 3-(1,3-dioxoisoindolin-2-yl)-3-phenylpropanamide, which can be found in K. Dredge (May 2005). "CC-1088Celgene". Current Opinion in Investigational Drugs. 6(5):513–7. PMID15912966);

[0353] For example, the PDE4 selective inhibitor of this application may contain BPN14770 (CAS#:1606974-33-7, Benzeneacetic acid, 4-[[2-(3-chlorophenyl)-6-(trifluoromethyl)-4-pyridinyl]methyl]-, which can be found in Ricciarelli R, et al. Memory-enhancing effects of GEBR-32a, a new PDE4D inhibitor holding promise for the treatment of Alzheimer's disease. Sci Rep. 2017 Apr 12; 7:46320.).

[0354] For example, the PDE4 selective inhibitor of this application may contain GSK356278 (CAS#:720704-34-7, 5-[5-[(2,4-dimethyl-5-thiazolyl)methyl]-1,3,4-oxadiazol-2-yl]-1-ethyl-N-(tetrahydro-2H-pyran-4-yl)-1H-Pyrazolo[3,4-b]pyridin-4-amine, which can be found at doi.org / 10.1124 / jpet.114.214155);

[0355] For example, the PDE4 selective inhibitor of this application may contain HT-0712 (CAS#:617720-02-2, 2-Piperidinone, 5-[3-(cyclopentyloxy)-4-Methoxyphenyl]-3-[(3-Methylphenyl)Methyl]-,(3S,5S)-, which can be found in US Patent 20040224316);

[0356] For example, the PDE4 selective inhibitor of this application may include TAK-648 (available at doi:10.1111 / cts.12436);

[0357] For example, the PDE4 selective inhibitor of this application may contain Zembrin (an extract of Sceletium tortuosum, the active ingredient of which may be mesembrenone, mesembrenol, mesembranol, and / or mesembrine, which can be found in DOI:10.1038 / npp.2013.183);

[0358] For example, the PDE4 selective inhibitor of this application may include ASP9831 (available at doi.org / 10.1016 / j.cgh.2014.01.040);

[0359] For example, the PDE4 selective inhibitor of this application may contain Etazolate (CAS#:51022-77-6, ethyl 1-ethyl-4-(2-propan-2-ylidenehydrazinyl)pyrazolo[3,4-b]pyridine-5-carboxylate, which can be found at doi.org / 10.1016 / j.neuroscience.2014.01.008);

[0360] For example, the PDE4 selective inhibitor of this application may contain Piclamilast (CAS#:144035-83-6, 3-cyclopentyloxy-N-(3,5-dichloropyridin-4-yl)-4-methoxybenzamide, which can be found at doi.org / 10.1124 / jpet.102.047407);

[0361] For example, the PDE4 selective inhibitor of this application may contain Rolipram (CAS#:61413-54-5, 4-(3-cyclopentyloxy-4-methoxyphenyl)pyrrolidin-2-one, which can be found at doi.org / 10.1073 / pnas.0402595101);

[0362] For example, the PDE4 selective inhibitor of this application may contain Cilomilast (CAS#:153259-65-5, 4-cyano-4-(3-cyclopentyloxy-4-methoxyphenyl)cyclohexane-1-carboxylic acid, which can be found at doi.org / 10.1164 / rccm.200212-1490OC);

[0363] For example, the PDE4 selective inhibitor of this application may include GSK256066 (available at doi.org / 10.1016 / j.pupt.2013.05.004);

[0364] For example, the PDE4 selective inhibitor of this application may contain AWD 12–281 (CAS#:257892-33-4, N-(3,5-dichloro-4-pyridinyl)-2-[1-(4-fluorobenzyl)-5-hydroxy-1H-indol-3-yl]-2-oxoacetamide, which can be found at doi.org / 10.1124 / jpet.103.053942);

[0365] For example, the PDE4 selective inhibitor of this application may include Quinolyl oxazole (see U.S. Patent 7,511,062);

[0366] For example, the PDE4 selective inhibitor of this application may contain DC-TA-46 (CAS#:109577-83-5, N-benzyl-6-chloro-2-piperazin-1-yl-4-pyrrolidin-1-ylpteridin-7-amine, which can be found at doi.org / 10.1210 / en.2004-0562);

[0367] For example, the PDE4 selective inhibitor of this application may contain filaminast (CAS#:141184-34-1, [(E)-1-(3-cyclopentyloxy-4-methoxyphenyl)ethylideneamino]carbamate, which can be found at doi.org / 10.1517 / 13543784.8.9.1301); and / or

[0368] For example, the PDE4 selective inhibitor of this application may contain Glaucine (CAS#:475-81-0, (6aS)-1,2,9,10-tetramethoxy-6-methyl-5,6,6a,7-tetrahydro-4H-dibenzo[de,g]quinoline, which can be found at doi.org / 10.1038 / sj.bjp.0702702).

[0369] In one aspect, the pharmaceutical composition of this application may comprise: a) an antibody comprising a heavy chain and a light chain, wherein the heavy chain comprises HCDR1 with an amino acid sequence as shown in any one of SEQ ID NO: 1, 11, 21, and 31, HCDR2 with an amino acid sequence as shown in any one of SEQ ID NO: 2, 12, 22, and 32, and HCDR3 with an amino acid sequence as shown in any one of SEQ ID NO: 3, 13, 23, and 33, and the light chain comprises LCDR1 with an amino acid sequence as shown in any one of SEQ ID NO: 4, 14, 24, and 34, LCDR2 with an amino acid sequence as shown in any one of SEQ ID NO: 5, 15, 25, and 35, and LCDR3 with an amino acid sequence as shown in any one of SEQ ID NO: 6, 16, 26, and 36; b) a compound of formula I or a pharmaceutically acceptable salt thereof:

[0370]

[0371] Wherein, one of R1 and R2 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and the other of R1 and R2 can be a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and

[0372] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino, or C1-C4 alkylcarbonylamino. R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl or C1-C4 alkoxy, R33 can be hydrogen, halogen, C1-C4 alkyl or C1-C4 alkoxy, R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxy carbonyl or amino, R35 can be hydrogen, halogen, amino or C1-C4 alkyl, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0373] For example, among them,

[0374] R1 can be hydrogen, C1-C6-alkoxy, C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0375] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0376] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonylamino. 2 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl or amino, R35 can be hydrogen, halogen, amino or C1-C4-alkyl, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0377] For example, among them,

[0378] R1 can be hydrogen, C1-C6-alkoxy, C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0379] R2 can be a methoxy group that is wholly or partially substituted with fluorine, and

[0380] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonylamino. 2 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl or amino, R35 can be hydrogen, halogen, amino or C1-C4-alkyl, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0381] For example, among them,

[0382] R1 can be C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, or benzoxy.

[0383] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0384] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonylamino. R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy; R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl or amino; R35 can be hydrogen, halogen, amino or C1-C4-alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0385] For example, among them,

[0386] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0387] R2 can be hydrogen, C1-C6-alkoxy, C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group wholly or partially substituted with fluorine, and

[0388] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1- R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl, or C1-C4-alkoxy; R33 can be hydrogen, halogen, C1-C4-alkyl, or C1-C4-alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, or amino; R35 can be hydrogen, halogen, amino, or C1-C4-alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0389] For example, among them,

[0390] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0391] R2 can be C3-C7-cycloalkylmethoxy or benzylmethoxy, and

[0392] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonylamino. 2 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl or amino, R35 can be hydrogen, halogen, amino or C1-C4-alkyl, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0393] For example, among them,

[0394] R1 can be a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine.

[0395] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0396] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0397] For example, among them,

[0398] R1 can be a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine.

[0399] R2 can be a methoxy group that is wholly or partially substituted with fluorine, and

[0400] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0401] For example, among them,

[0402] R1 can be C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, or benzoxy.

[0403] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0404] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0405] For example, among them,

[0406] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0407] R2 can be a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0408] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0409] For example, among them,

[0410] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0411] R2 can be C3-C5-cycloalkylmethoxy or benzylmethoxy, and

[0412] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0413] For example, among them,

[0414] R1 can be a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine.

[0415] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0416] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0417] For example, among them,

[0418] R1 can be a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine.

[0419] R2 can be a methoxy group that is wholly or partially substituted with fluorine, and

[0420] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0421] For example, among them,

[0422] R1 can be C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, or benzoxy.

[0423] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0424] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0425] For example, among them,

[0426] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0427] R2 can be a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0428] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0429] For example, among them,

[0430] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0431] R2 can be C3-C5-cycloalkylmethoxy or benzylmethoxy, and

[0432] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0433] For example, among them,

[0434] R1 can be a difluoromethoxy group.

[0435] R2 can be methoxy, ethoxy, isopropoxy, isobutoxy, cyclopentoxy, cyclopropylmethoxy, cyclobutylmethoxy, difluoromethoxy, or 2,2,2-trifluoroethoxy, and R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, or 2,6-dimethylphenyl. Phenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl or 2,6-dichloropyridin-3-yl;

[0436] For example, among them,

[0437] R1 can be a difluoromethoxy group.

[0438] R2 can be methoxy, cyclopropylmethoxy, cyclobutylmethoxy, or difluoromethoxy, and

[0439] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0440] For example, among them,

[0441] R1 can be methoxy, n-propoxy, n-butoxy, cyclopropylmethoxy, or 2,2,2-trifluoroethoxy.

[0442] R2 can be difluoromethoxy, and

[0443] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0444] For example, among them,

[0445] R1 can be a difluoromethoxy group.

[0446] R2 can be cyclopropylmethoxy, and

[0447] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0448] For example, among them,

[0449] R1 can be a C3-C7-cycloalkoxy or a C3-C7-cycloalkylmethoxy, and R2 can be a C1-C4-alkoxy that is wholly or partially fluorinated; or R1 can be a C1-C4-alkoxy that is wholly or partially fluorinated, and R2 can be a C3-C7-cycloalkylmethoxy; and

[0450] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be hydroxyl, halogen, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, or C1-C4-alkylcarbonyloxy; R32 can be hydrogen, hydroxyl, halogen, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy; R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 can be hydroxyl, halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl; R35 can be hydrogen, halogen, amino or C1-C4-alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0451] For example, among them,

[0452] R1 can be C3-C7-cycloalkoxy or C3-C7-cycloalkylmethoxy.

[0453] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0454] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be hydroxyl, halogen, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, or C1-C4-alkylcarbonyloxy; R32 can be hydrogen, hydroxyl, halogen, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy; R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 can be hydroxyl, halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl; R35 can be hydrogen, halogen, amino or C1-C4-alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0455] For example, among them,

[0456] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0457] R2 can be C3-C7-cycloalkylmethoxy, and

[0458] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be hydroxyl, halogen, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl or C1-C4-alkylcarbonyloxy; R32 can be hydrogen, hydroxyl, halogen, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy; R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 can be hydroxyl, halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl; R35 can be hydrogen, halogen or C1-C4-alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0459] For example, among them,

[0460] R1 can be C3-C5-cycloalkoxy or C3-C5-cycloalkylmethoxy.

[0461] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0462] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0463] For example, among them,

[0464] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0465] R2 can be C3-C5-cycloalkylmethoxy, and

[0466] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0467] For example, among them,

[0468] R1 can be C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, or benzoxy.

[0469] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0470] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0471] For example, among them,

[0472] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0473] R2 can be C3-C5-cycloalkylmethoxy, and

[0474] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0475] For example, among them,

[0476] R1 can be a difluoromethoxy group.

[0477] R2 can be cyclopropylmethoxy, and

[0478] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0479] For example, R1 can be difluoromethoxy, R2 can be cyclopropylmethoxy, and R3 can be 3,5-dichloropyridin-4-yl.

[0480] For example, the PDE4 selective inhibitor of this application may contain Roflumilast or a derivative thereof.

[0481] For example, derivatives of Roflumilast in this application may contain benzamide and / or bezafibrate.

[0482] For example, the ratio of the effective amount of the PDE4 selective inhibitor to the effective amount of the immune checkpoint inhibitor in this application can be from about 1:10 to about 1:5000. For example, the ratio of the effective amount of the PDE4 selective inhibitor to the effective amount of the immune checkpoint inhibitor in this application can be from about 9:1 to about 1:4.

[0483] For example, the effective amount ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from about 9:1 to about 1:4. For example, the effective amount ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from about 8:1 to about 1:4, from about 7:1 to about 1:4, from about 6:1 to about 1:4, from about 5:1 to about 1:4, from about 4:1 to about 1:4, from about 3:1 to about 1:4, from about 2:1 to about 1:4, from about 1:1 to about 1:4, from about 1:2 to about 1:4, or from about 1:3 to about 1:4. For example, the effective amount ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application... The effective ratio of immune checkpoint inhibitors can be 9:1 to about 1:3, about 8:1 to about 1:3, about 7:1 to about 1:3, about 6:1 to about 1:3, about 5:1 to about 1:3, about 4:1 to about 1:3, about 3:1 to about 1:3, about 2:1 to about 1:3, about 1:1 to about 1:3, or about 1:2 to about 1:3. For example, the effective ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be 9:1 to about 1:2, about 8:1 to about 1:2, about 7:1 to about 1:2, about 6:1 to about 1:2, about 5:1 to about 1:2, about 4:1 to about 1:3. The effective ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be 1:2, about 3:1 to about 1:2, about 2:1 to about 1:2, or about 1:1 to about 1:2. For example, the effective ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be 9:1 to about 1:1, about 8:1 to about 1:1, about 7:1 to about 1:1, about 6:1 to about 1:1, about 5:1 to about 1:1, about 4:1 to about 1:1, about 3:1 to about 1:1, or about 2:1 to about 1:1. For example, the effective ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be 9:1 to about 3:1, about 8:1 to about 1:1, about 7:1 to about 1:1, about 6:1 to about 1:1, about 5:1 to about 1:1, about 4:1 to about 1:1, about 3:1 to about 1:1, or about 2:1 to about 1:1. The effective ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from 7:1 to about 3:1, from about 6:1 to about 3:1, from about 5:1 to about 3:1, or from about 4:1 to about 3:1. For example, the effective ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from 9:1 to about 6:1, from about 8:1 to about 6:1, or from about 7:1 to about 6:1. For example, the effective ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from 9:1 to about 7:1, or from about 8:1 to about 7:1. For example, the effective ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from 9:1 to about 8:1.

[0484] For example, the effective amount ratio in this application may include the effective amount mole ratio and / or the effective amount mass ratio.

[0485] For example, the mass ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from about 5000:1 to about 1:5000.

[0486] For example, the mass ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from about 9:1 to about 1:4. For example, the mass ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from about 8:1 to about 1:4, from about 7:1 to about 1:4, from about 6:1 to about 1:4, from about 5:1 to about 1:4, from about 4:1 to about 1:4, from about 3:1 to about 1:4, from about 2:1 to about 1:4, from about 1:1 to about 1:4, from about 1:2 to about 1:4, or from about 1:3 to about 1:4. For example, the mass ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from about 9:1 to about 1:4. The mass ratio of the checkpoint inhibitors can be from 9:1 to about 1:3, from about 8:1 to about 1:3, from about 7:1 to about 1:3, from about 6:1 to about 1:3, from about 5:1 to about 1:3, from about 4:1 to about 1:3, from about 3:1 to about 1:3, from about 2:1 to about 1:3, from about 1:1 to about 1:3, or from about 1:2 to about 1:3. For example, the mass ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from 9:1 to about 1:2, from about 8:1 to about 1:2, from about 7:1 to about 1:2, from about 6:1 to about 1:2, from about 5:1 to about 1:2, from about 4:1 to about 1:3. :2, about 3:1 to about 1:2, about 2:1 to about 1:2, or about 1:1 to about 1:2. For example, the mass ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor of this application can be about 9:1 to about 1:1, about 8:1 to about 1:1, about 7:1 to about 1:1, about 6:1 to about 1:1, about 5:1 to about 1:1, about 4:1 to about 1:1, about 3:1 to about 1:1, or about 2:1 to about 1:1. For example, the mass ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor of this application can be about 9:1 to about 3:1, about 8:1 to about 3:1, or about 1:1 to about 1:2. The mass ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from 7:1 to about 3:1, from about 6:1 to about 3:1, from about 5:1 to about 3:1, or from about 4:1 to about 3:1. For example, the mass ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from 9:1 to about 6:1, from about 8:1 to about 6:1, or from about 7:1 to about 6:1. For example, the mass ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from 9:1 to about 7:1, or from about 8:1 to about 7:1. For example, the mass ratio of the PDE4 selective inhibitor to the immune checkpoint inhibitor in this application can be from 9:1 to about 8:1.

[0487] For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may each be from different sources, such as being prepared, manufactured, or sold by different manufacturers. For example, the immune checkpoint inhibitor prepared, manufactured, or sold by this application need not be a single component or pure, as long as it contains a compound or its solvates, hydrates, salts capable of releasing the immune checkpoint inhibitor in vivo or in vitro, and / or contains analogs of the immune checkpoint inhibitor of this application (e.g., wherein one or more amino acids of the immune checkpoint inhibitor of this application are replaced by another amino acid, and wherein the immune checkpoint inhibitor of this application substantially maintains the stable activity of the immune checkpoint inhibitor of this application in vitro or in vivo), all are within the scope of this application. Similarly, the PDE4 selective inhibitors prepared, produced, or sold need not be single-component or pure. As long as they contain any one or more of the PDE4 selective inhibitors of this application that can release in vivo or in vitro, or their solvates, hydrates, salts, and / or analogs containing any one or more of the PDE4 selective inhibitors of this application (e.g., those containing group modifications or substitutions, and the analogs substantially retain any PDE4 selective inhibitors in vitro or in vivo), they are all within the scope of this application.

[0488] For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application can each be contained in different containers. Alternatively, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application can be contained in the same container.

[0489] For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may be set according to their effective ratio or not.

[0490] For example, the PDE4 selective inhibitors of this application may be present in one or more containers, such as two or more, three or more, four or more, five or more, six or more, seven or more, eight or more, nine or more, ten or more, eleven or more, twelve or more.

[0491] For example, the immune checkpoint inhibitors of this application may be present in one or more containers, such as two or more, three or more, four or more, five or more, six or more, seven or more, eight or more, nine or more, ten or more, eleven or more, twelve or more.

[0492] For example, the containers of this application may include medicine boxes, medicine containers, medicine bottles, medicine bags, blister packs, tubes, syringes, etc.; for example, the medicine bottles of this application may include sealed glass ampoules, test tubes, vials, flasks, bottles, etc.; for example, the containers of this application may be made of packaging materials such as organic polymers such as glass, polycarbonate, and polystyrene, or foil lined with ceramics, metals, composite films, cellophane, aluminum or alloys, etc., as well as any other suitable materials that can be used to hold reagents.

[0493] For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may each exist in different containers and may be formulated into formulations simultaneously or separately with suitable carriers when needed.

[0494] For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application can be mixed to form a suitable formulation.

[0495] For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application can each be formulated into different suitable formulations.

[0496] For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may each exist in different containers in the form of a formulation.

[0497] For example, the drug combination of this application may include a first formulation and a second formulation. The first formulation of this application may include the immune checkpoint inhibitor of this application and a pharmaceutically acceptable first carrier, and the second formulation of this application may include the PDE4 selective inhibitor of this application and a pharmaceutically acceptable second carrier.

[0498] For example, the first formulation and the second formulation of this application may be the same dosage form or different dosage forms.

[0499] For example, both the first and second formulations of this application can be any one of the following dosage forms: pills, powders, tablets, granules, gels, hard capsules, soft capsules, syrups, mixtures, elixirs, injections, aerosols, ointments, films, suppositories, and drop pills, or any different combinations thereof. For example, both the first and second formulations of this application can be injections or tablets. For example, the first formulation of this application can be a tablet, and the second formulation can be an injection. For example, the first formulation of this application can be an injection, and the second formulation can be a tablet. For example, the first formulation of this application can be a tablet, and the second formulation can be granules.

[0500] For example, the first formulation and the second formulation of this application may exist in formulation forms suitable for the same administration method. For example, both the first formulation and the second formulation of this application may be tablets, granules, hard capsules, soft capsules, or syrups suitable for oral administration. For example, both the first formulation and the second formulation of this application may be injectable preparations suitable for injection.

[0501] For example, the first formulation and the second formulation of this application can exist in formulation forms suitable for different administration methods. For example, the first formulation and the second formulation of this application can be tablets, granules, hard capsules, soft capsules, or syrups suitable for oral administration. For example, the first formulation of this application can be an injectable preparation suitable for injection, and the second formulation of this application can be tablets, granules, hard capsules, soft capsules, or syrups suitable for oral administration. For example, the first formulation of this application can be an injectable preparation suitable for injection, and the second formulation of this application can be a sustained-release formulation encapsulated in microcapsules or the like.

[0502] For example, the pharmaceutical composition of this application may include a pharmaceutical composition, such as the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application.

[0503] For example, the content of the PDE4 selective inhibitor in the pharmaceutical composition of this application may be from about 20% to about 90% (w / w).

[0504] For example, the content of the PDE4 selective inhibitor in the pharmaceutical composition of this application may be about 20% to about 90% (w / w), about 30% to about 90% (w / w), about 40% to about 90% (w / w), about 50% to about 90% (w / w), about 60% to about 90% (w / w), about 70% to about 90% (w / w), about 80% to about 90% (w / w), about 85% to about 90% (w / w), or about 89% to about 90% (w / w). The content of the PDE4 selective inhibitor in the pharmaceutical composition of this application may be about 20% to about 80% (w / w), about 30% to about 80% (w / w), about 40% to about 80% (w / w), about 50% to about 80% (w / w), about 60% to about 80% (w / w), or about 70% to about 80% (w / w). For example, the content of the PDE4 selective inhibitor in the pharmaceutical composition of this application may be about 20% to about 70% (w / w), about 30% to about 70% (w / w), about 40% to about 70% (w / w), about 50% to about 70% (w / w), or about 60% to about 70% (w / w). For example, the content of the PDE4 selective inhibitor in the pharmaceutical composition of this application can be about 20% to about 60% (w / w), about 30% to about 60% (w / w), about 40% to about 60% (w / w), or about 50% to about 60% (w / w). The content of the PDE4 selective inhibitor in the pharmaceutical composition of this application may be about 20% to about 50% (w / w), about 30% to about 50% (w / w), or about 40% to about 50% (w / w). For example, the content of the PDE4 selective inhibitor in the pharmaceutical composition of this application may be about 20% to about 40% (w / w), or about 30% to about 40% (w / w). For example, the content of the PDE4 selective inhibitor in the pharmaceutical composition of this application may be about 20% to about 30% (w / w) or about 25% to about 30% (w / w).

[0505] For example, the content of the immune checkpoint inhibitor in the pharmaceutical composition of this application may be from about 10% to about 80% (w / w).

[0506] For example, the content of the immune checkpoint inhibitor in the pharmaceutical composition of this application may be about 10% to about 80% (w / w), about 20% to about 80% (w / w), about 30% to about 80% (w / w), about 40% to about 80% (w / w), about 50% to about 80% (w / w), about 60% to about 80% (w / w), about 70% to about 80% (w / w), or about 75% to about 80% (w / w). The content of the immune checkpoint inhibitor can be from about 10% to about 70% (w / w), from about 20% to about 70% (w / w), from about 30% to about 70% (w / w), from about 40% to about 70% (w / w), from about 50% to about 70% (w / w), or from about 60% to about 70% (w / w). For example, the content of the immune checkpoint inhibitor in the pharmaceutical composition of this application can be from about 10% to about 60% (w / w), from about 20% to about 60% (w / w). The content of the immune checkpoint inhibitor in the pharmaceutical composition of this application may be approximately 30% to approximately 60% (w / w), approximately 40% to approximately 60% (w / w), or approximately 50% to approximately 60% (w / w). For example, the content of the immune checkpoint inhibitor in the pharmaceutical composition of this application may be approximately 10% to approximately 50% (w / w), approximately 20% to approximately 50% (w / w), approximately 30% to approximately 50% (w / w), or approximately 40% to approximately 50% (w / w). The content of the immune checkpoint inhibitor in the pharmaceutical composition of this application may be about 10% to about 40% (w / w), about 20% to about 40% (w / w), or about 30% to about 40% (w / w). For example, the content of the immune checkpoint inhibitor in the pharmaceutical composition of this application may be about 10% to about 30% (w / w), or about 20% to about 30% (w / w). For example, the content of the immune checkpoint inhibitor in the pharmaceutical composition of this application may be about 10% to about 20% (w / w) or about 15% to about 20% (w / w).

[0507] Reagent test kit

[0508] The kit of this application may include the drug combination of this application. The drug combination of this application may be provided in the form of a kit, wherein the different components of the drug combination may be packaged in different containers and may be mixed before administration, or may be administered separately without mixing.

[0509] For example, separate packaging can be used to allow for long-term storage without losing the function of the active ingredients.

[0510] For example, the formulation contained in the kit can be contained in any type of container where the formulation components can remain effective for a long period of time, are not adsorbed by the container material, and are not easily deteriorated. For example, a sealed glass ampoule, which can be made of glass, polycarbonate, polystyrene, or other organic polymers, ceramics, metals, or any other suitable material commonly used to hold reagents. Other suitable containers include simple bottles made of materials similar to ampoules, and packaging materials lined with foil such as aluminum or alloys. Other containers can include test tubes, vials, flasks, bottles, syringes, or the like. The container has a sterile access port for the bottle, which may have a stopper that can be penetrated by a hypodermic needle.

[0511] For example, the kit may also contain a buffer solution packaged in the presence of a neutral, non-reactive gas such as nitrogen.

[0512] For example, the kit may also include administration aids such as measuring cups or spoons for oral administration, or syringes, tubing, or needles for injection.

[0513] For example, instructions for use may also be included with the kit. Instructions for use of the kit consisting of this drug combination may be printed on paper or other materials, and / or supplied as electrically or electromagnetically readable media such as floppy disks, CD-ROMs, DVD-ROMs, Zip disks, videotapes, and audiotapes. Detailed instructions for use may be physically included with the kit or posted at a website designated by the kit manufacturer or distributor, or notified via email.

[0514] For example, the drug combination provided in this application may be described in the instruction manual of this application.

[0515] For example, the purpose or method provided by this application may be described in the instruction manual of this application.

[0516] Uses and methods

[0517] This application provides the use of a combination of the present application's PDE4 selective inhibitor and the present application's immune checkpoint inhibitor in the preparation of a medicament for the prevention and / or treatment of tumors. This application also provides the use of the PDE4 selective inhibitor in the preparation of a medicament for the prevention and / or treatment of tumors.

[0518] This application also provides methods for preventing and / or treating tumors, which may include administration to a subject in need:

[0519] a) An effective dose of immune checkpoint inhibitors; and

[0520] b) An effective amount of a selective PDE4 inhibitor.

[0521] For example, the tumor may include solid tumors and / or non-solid tumors.

[0522] For example, the solid tumor may be selected from the group consisting of colorectal cancer, breast cancer, and melanoma.

[0523] For example, the tumors include colon cancer and / or melanoma.

[0524] For example, the tumor includes metastatic tumors.

[0525] For example, the tumor includes tumors that have metastasized to the liver.

[0526] For example, the tumor includes colon cancer that has metastasized to the liver.

[0527] On one hand, the PDE4 selective inhibitors, drug combinations, or kits of this application can be used to prevent and / or treat tumors, and the tumor volume can be reduced by about 1%, about 2%, about 3%, about 4%, about 5%, about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, or about 100% compared to the blank control group. For example, the PDE4 selective inhibitors, drug combinations, or kits of this application can be used to prevent and / or treat tumors, and the tumor volume can be reduced by about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 20, about 30, about 40, about 50, about 60, about 70, about 80, about 90, about 100, or about 1000 times compared to the blank control group.

[0528] On one hand, the PDE4 selective inhibitors, drug combinations, or kits of this application can be used to prevent and / or treat metastatic tumors, and the volume of metastatic tumors can be reduced by about 1%, about 2%, about 3%, about 4%, about 5%, about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, or about 100% compared to the blank control group. For example, the PDE4 selective inhibitors, drug combinations, or kits of this application can be used to prevent and / or treat metastatic tumors, and the volume of metastatic tumors can be reduced by about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 20, about 30, about 40, about 50, about 60, about 70, about 80, about 90, about 100, or about 1000 times compared to the blank control group.

[0529] On the other hand, this application provides a method for preventing and / or treating tumors, which may include administering the PDE4 selective inhibitor, drug combination, or kit of this application to a subject in need for the prevention and / or treatment of tumors, wherein the tumor volume may be reduced by about 1%, about 2%, about 3%, about 4%, about 5%, about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, or about 100% compared to a blank control group. For example, the tumor volume may be reduced by about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 20, about 30, about 40, about 50, about 60, about 70, about 80, about 90, about 100, or about 1000 times compared to a blank control group.

[0530] On the other hand, this application provides a method for preventing and / or treating metastatic tumors, which may include administering the PDE4 selective inhibitor, drug combination, or kit of this application to a subject in need for the prevention and / or treatment of metastatic tumors, wherein the volume of metastatic tumors may be reduced by about 1%, about 2%, about 3%, about 4%, about 5%, about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, or about 100% compared to a blank control group. For example, the volume of metastatic tumors may be reduced by about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 20, about 30, about 40, about 50, about 60, about 70, about 80, about 90, about 100, or about 1000 times compared to a blank control group.

[0531] On the other hand, the PDE4 selective inhibitors, drug combinations, or kits of this application can be used to prepare drugs for the prevention and / or treatment of tumors, wherein the tumor volume can be reduced by about 1%, about 2%, about 3%, about 4%, about 5%, about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, or about 100% compared to a blank control group. For example, the tumor volume can be reduced by about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 20, about 30, about 40, about 50, about 60, about 70, about 80, about 90, about 100, or about 1000 times compared to a blank control group.

[0532] On the other hand, the PDE4 selective inhibitors, drug combinations, or kits of this application can be used to prepare drugs for the prevention and / or treatment of tumors, wherein the volume of metastatic tumors can be reduced by about 1%, about 2%, about 3%, about 4%, about 5%, about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, or about 100% compared to a blank control group. For example, the volume of metastatic tumors can be reduced by about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 20, about 30, about 40, about 50, about 60, about 70, about 80, about 90, about 100, or about 1000 times compared to a blank control group.

[0533] For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application can be configured to be administered to a subject simultaneously.

[0534] For example, the subject may be simultaneously administered the PDE4 selective inhibitor of this application and the immune checkpoint inhibitor of this application.

[0535] For example, the simultaneous administration to the subject may include administering the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application to the subject at a time interval not exceeding 1 hour. For example, the time interval may be 60 minutes, 55 minutes, 50 minutes, 45 minutes, 40 minutes, 35 minutes, 30 minutes, 25 minutes, 20 minutes, 15 minutes, 10 minutes, 8 minutes, 5 minutes, 3 minutes, 2 minutes, or 1 minute, or they may be administered together in a mixed form.

[0536] For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application can be configured to be administered to subjects, respectively.

[0537] For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may be administered sequentially to the subject.

[0538] For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application can be configured to be administered to the subject in any order. The administration order may include administering the PDE4 selective inhibitor first, followed by the immune checkpoint inhibitor, or vice versa. For example, administering the PDE4 selective inhibitor and the immune checkpoint inhibitor to the subject separately may include an interval greater than 1 hour between administrations. For example, the time interval may be 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, 5.5 hours, 6 hours, 6.5 hours, 7 hours, 7.5 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 15 hours, 18 hours, 21 hours, 24 hours, 2 days, 3 days, 4 days, 5 days, 6 days, 7 days, or longer.

[0539] For example, the sequential administration to the subject may include an interval greater than 1 hour between the administration of the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application to the subject. For example, the time interval may be 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, 5.5 hours, 6 hours, 6.5 hours, 7 hours, 7.5 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 15 hours, 18 hours, 21 hours, 24 hours, 2 days, 3 days, 4 days, 5 days, 6 days, 7 days, or longer.

[0540] For example, administration of the PDE4 selective inhibitor of this application may include a single administration.

[0541] For example, administering the PDE4 selective inhibitor of this application may include administering it two or more times consecutively, such as three or more times, four or more times, five or more times, six or more times, seven or more times, eight or more times, nine or more times, ten or more times, followed by administering the immune checkpoint inhibitor of this application.

[0542] For example, administering the immune checkpoint inhibitor of this application may include a single administration.

[0543] For example, administering the immune checkpoint inhibitor of this application may include administering it two or more times consecutively, such as three or more times, four or more times, five or more times, six or more times, seven or more times, eight or more times, nine or more times, ten or more times, followed by administering the PDE4 selective inhibitor of this application.

[0544] For example, the drug of this application can be configured such that the PDE4 selective inhibitor of this application and the immune checkpoint inhibitor of this application are administered at a mass ratio of about 1:5 to about 1:5000.

[0545] For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application can be administered at a mass ratio of about 1:5 to about 1:5000.

[0546] For example, the drug can be formulated such that the PDE4 selective inhibitor of this application and the immune checkpoint inhibitor of this application are administered at an effective ratio of about 8:1 to about 1:4, about 7:1 to about 1:4, about 6:1 to about 1:4, about 5:1 to about 1:4, about 4:1 to about 1:4, about 3:1 to about 1:4, about 2:1 to about 1:4, about 1:1 to about 1:4, about 1:2 to about 1:4, or about 1:3 to about 1:4. For example, the PDE4 selective inhibitor of this application and the immune checkpoint inhibitor of this application can be administered at an effective ratio of 9:1 to about 1:3, about 8:1 to about 1:3, or about 7:1. The effective dose ratios can be approximately 1:3, approximately 6:1 to approximately 1:3, approximately 5:1 to approximately 1:3, approximately 4:1 to approximately 1:3, approximately 3:1 to approximately 1:3, approximately 2:1 to approximately 1:3, approximately 1:1 to approximately 1:3, or approximately 1:2 to approximately 1:3. For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application can be administered at effective dose ratios of approximately 9:1 to approximately 1:2, approximately 8:1 to approximately 1:2, approximately 7:1 to approximately 1:2, approximately 6:1 to approximately 1:2, approximately 5:1 to approximately 1:2, approximately 4:1 to approximately 1:2, approximately 3:1 to approximately 1:2, approximately 2:1 to approximately 1:2, or approximately 1:1 to approximately 1:3. The effective dose ratio of 2 is applied. For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may be applied at an effective dose ratio of 9:1 to about 1:1, about 8:1 to about 1:1, about 7:1 to about 1:1, about 6:1 to about 1:1, about 5:1 to about 1:1, about 4:1 to about 1:1, about 3:1 to about 1:1, or about 2:1 to about 1:1. For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may be applied at an effective dose ratio of 9:1 to about 3:1, about 8:1 to about 3:1, about 7:1 to about 3:1, about 6:1 to about 3:1, or about 5:1. The effective amount ratios of the present application PDE4 selective inhibitor and the present application immune checkpoint inhibitor can be applied at effective amount ratios of 9:1 to 6:1, 8:1 to 6:1, or 7:1 to 6:1. For example, the effective amount ratios of the present application PDE4 selective inhibitor and the present application immune checkpoint inhibitor can be applied at effective amount ratios of 9:1 to 7:1, 8:1 to 7:1, or 9:1 to 7:1. For example, the effective amount ratios of the present application PDE4 selective inhibitor and the present application immune checkpoint inhibitor can be applied at effective amount ratios of 9:1 to 8:1.

[0547] For example, the drug may be configured such that the PDE4 selective inhibitor of this application and the immune checkpoint inhibitor of this application are administered at an effective ratio of about 1:5 to about 1:5000.

[0548] For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application can be administered at a mass ratio of about 1:5 to about 1:5000.

[0549] For example, the drug can be formulated such that the PDE4 selective inhibitor of this application and the immune checkpoint inhibitor of this application are administered at a mass ratio of about 8:1 to about 1:4, about 7:1 to about 1:4, about 6:1 to about 1:4, about 5:1 to about 1:4, about 4:1 to about 1:4, about 3:1 to about 1:4, about 2:1 to about 1:4, about 1:1 to about 1:4, about 1:2 to about 1:4, or about 1:3 to about 1:4. For example, the PDE4 selective inhibitor of this application and the immune checkpoint inhibitor of this application can be administered at a mass ratio of 9:1 to about 1:3, about 8:1 to about 1:3, about 7... The PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may be administered at mass ratios of 9:1 to 1:2, about 8:1 to 1:2, about 7:1 to 1:2, about 6:1 to 1:2, about 5:1 to 1:2, about 6:1 to 1:2, about 5:1 to 1:2, about 2:1 to 1:2, about 4:1 to 1:2, about 3:1 to 1:2, about 2:1 to 1:2, or about 1:2 to 1:3. For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may be administered at mass ratios of 9:1 to 1:2, about 8:1 to 1:2, about 7:1 to 1:2, about 6:1 to 1:2, about 5:1 to 1:2, about 4:1 to 1:2, about 3:1 to 1:2, about 2:1 to 1:2, or about 1:1. The PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may be administered at a mass ratio of approximately 1:2. For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may be administered at a mass ratio of approximately 9:1 to approximately 1:1, approximately 8:1 to approximately 1:1, approximately 7:1 to approximately 1:1, approximately 6:1 to approximately 1:1, approximately 5:1 to approximately 1:1, approximately 4:1 to approximately 1:1, approximately 3:1 to approximately 1:1, or approximately 2:1 to approximately 1:1. For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may be administered at a mass ratio of approximately 9:1 to approximately 3:1, approximately 8:1 to approximately 3:1, approximately 7:1 to approximately 3:1, approximately 6:1 to approximately 3:1. The PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may be administered at a mass ratio of about 5:1 to about 3:1, or about 4:1 to about 3:1. For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may be administered at a mass ratio of about 9:1 to about 6:1, about 8:1 to about 6:1, or about 7:1 to about 6:1. For example, the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application may be administered at a mass ratio of about 9:1 to about 8:1.

[0550] For example, the effective amount ratio may include the effective amount mole ratio and / or the effective amount mass ratio.

[0551] For example, the administration may include intravenous, arterial, subcutaneous, intramuscular, intradermal, intracavitary, intratumoral, or peritumoral administration. For example, it may be administered orally or topically. The method of administration can depend on various factors; for example, to achieve an effective concentration at the tumor site, the drug can be administered via various routes, such as selective arterial infusion, intracavitary infusion, intraperitoneal or intrapleural administration, and spinal canal administration. For example, local administration may be performed, such as selective arterial, intratumoral, or peritumoral injection or placement, or, for example, slow release within, around, or in the tumor cavity.

[0552] PDE4 selective inhibitors

[0553] In this application, the PDE4 selective inhibitor may include a substance capable of at least partially disrupting or inhibiting the activity of one or more members of the PDE4 subfamily.

[0554] For example, the PDE4 subfamily members may include PDE4A, PDE4B, PDE4C and / or PDE4D.

[0555] For example, the PDE4 selective inhibitor may include substances that at least partially disrupt or inhibit the activity of PDE4A, PDE4B, PDE4C, or PDE4D.

[0556] For example, the PDE4 selective inhibitor may include substances that at least partially disrupt or inhibit the activity of PDE4C and PDE4D. For example, the PDE4 selective inhibitor may include substances that at least partially disrupt or inhibit the activity of PDE4B and PDE4C. For example, the PDE4 selective inhibitor may include substances that at least partially disrupt or inhibit the activity of PDE4B and PDE4D. For example, the PDE4 selective inhibitor may include substances that at least partially disrupt or inhibit the activity of PDE4A and PDE4B. For example, the PDE4 selective inhibitor may include substances that at least partially disrupt or inhibit the activity of PDE4A and PDE4C. For example, the PDE4 selective inhibitor may include substances that at least partially disrupt or inhibit the activity of PDE4A and PDE4D.

[0557] For example, the PDE4 selective inhibitor may include substances that at least partially disrupt or inhibit the activity of PDE4A, PDE4B, and PDE4C. For example, the PDE4 selective inhibitor may include substances that at least partially disrupt or inhibit the activity of PDE4A, PDE4C, and PDE4D. For example, the PDE4 selective inhibitor may include substances that at least partially disrupt or inhibit the activity of PDE4A, PDE4B, and PDE4D. For example, the PDE4 selective inhibitor may include substances that at least partially disrupt or inhibit the activity of PDE4B, PDE4C, and PDE4D.

[0558] For example, the PDE4 selective inhibitor may include substances that at least partially disrupt or inhibit the activity of PDE4A, PDE4B, PDE4C and PDE4C.

[0559] For example, the at least partial disruption or obstruction may include at least 30%, 40%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95% disruption or obstruction.

[0560] For example, the PDE4 selective inhibitors described herein may substantially not disrupt or inhibit the activity of other members of the PDEs family (other than PDE4). For example, substantially not disrupting or inhibiting may include disruption or inhibition of up to 30%, 25%, 20%, 18%, 15%, 13%, 10%, 8%, 5%, 3%, or 1%.

[0561] For example, other members of the PDEs family may include PDE1 subfamily members, PDE2 subfamily members, PDE3 subfamily members, PDE5 subfamily members, PDE6 subfamily members, PDE7 subfamily members, PDE8 subfamily members, PDE9 subfamily members, PDE10 subfamily members, PDE11 subfamily members, and PDE12 subfamily members.

[0562] For example, the activity may include the activity of hydrolyzing cAMP and / or cGMP. For example, the activity of hydrolyzing cAMP and / or cGMP may be determined by any method known to those skilled in the art.

[0563] For example, the selective PDE4 inhibitors may include Apremilast (Otezla), Crisaborole (Eucrisa), Drotaverine, CC-1088 (see K. Dredge (May 2005). "CC-1088Celgene". Current Opinion in Investigational Drugs. 6(5):513–7. PMID 15912966), BPN14770 (see Ricciarelli R, et al. Memory-enhancing effects of GEBR-32a, a new PDE4D inhibitor holding promise for the treatment of Alzheimer's disease. Sci Rep. 2017 Apr). 12; 7:46320.), GSK356278 (available at doi.org / 10.1124 / jpet.114.214155), HT-0712 (available at US Patent 20040224316), TAK-648 (available at doi:10.1111 / cts.12436), Zembrin (available at DOI:10.1038 / npp.2013.183), ASP9831 (available at doi.org / 10.1016 / j.cgh.2014.01.040), Etazolate (available at doi.org / 10 .1016 / j.neuroscience.2014.01.008), Piclamilast (can be found at doi.org / 10.1124 / jpet.102.047407), Rolipram (can be found at doi.org / 10.1073 / pnas.0402595101), Cilomilast (can be found at doi.org / 10.1164 / rccm.200212-1490OC), GSK256066 (can be found at doi.org / 10.1016 / j.pupt.2013.05.004), AWD 12–281 (available at doi.org / 10.1124 / jpet.103.053942), Quinolyl oxazole (available at US Patent 7511062), DC-TA-46 (available at doi.org / 10.1210 / en.2004-0562), and Filaminast (available at doi.org / 10.1517 / 13543784.8.9).1301) and / or Glaucine (available at doi.org / 10.1038 / sj.bjp.0702702).

[0564] For example, this application provides compounds of Formula I or pharmaceutically acceptable salts thereof:

[0565]

[0566] Wherein, one of R1 and R2 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and the other of R1 and R2 can be a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and

[0567] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino, or C1-C4 alkylcarbonylamino. R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl or C1-C4 alkoxy, R33 can be hydrogen, halogen, C1-C4 alkyl or C1-C4 alkoxy, R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxy carbonyl or amino, R35 can be hydrogen, halogen, amino or C1-C4 alkyl, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0568] For example, among them,

[0569] R1 can be hydrogen, C1-C6-alkoxy, C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0570] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0571] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonylamino. 2 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl or amino, R35 can be hydrogen, halogen, amino or C1-C4-alkyl, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0572] For example, among them,

[0573] R1 can be hydrogen, C1-C6-alkoxy, C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0574] R2 can be a methoxy group that is wholly or partially substituted with fluorine, and

[0575] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonylamino. 2 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl or amino, R35 can be hydrogen, halogen, amino or C1-C4-alkyl, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0576] For example, among them,

[0577] R1 can be C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, or benzoxy.

[0578] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0579] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonylamino. R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy; R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl or amino; R35 can be hydrogen, halogen, amino or C1-C4-alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0580] For example, among them,

[0581] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0582] R2 can be hydrogen, C1-C6-alkoxy, C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group wholly or partially substituted with fluorine, and

[0583] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonylamino. 2 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl or amino, R35 can be hydrogen, halogen, amino or C1-C4-alkyl, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0584] For example, among them,

[0585] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0586] R2 can be C3-C7-cycloalkylmethoxy or benzylmethoxy, and

[0587] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino, or C1-C4-alkylcarbonylamino. 2 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl or amino, R35 can be hydrogen, halogen, amino or C1-C4-alkyl, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0588] For example, among them,

[0589] R1 can be a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine.

[0590] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0591] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0592] For example, among them,

[0593] R1 can be a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine.

[0594] R2 can be a methoxy group that is wholly or partially substituted with fluorine, and

[0595] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0596] For example, among them,

[0597] R1 can be C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, or benzoxy.

[0598] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0599] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0600] For example, among them,

[0601] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0602] R2 can be a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0603] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0604] For example, among them,

[0605] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0606] R2 can be C3-C5-cycloalkylmethoxy or benzylmethoxy, and

[0607] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0608] For example, among them,

[0609] R1 can be a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine.

[0610] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0611] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0612] For example, among them,

[0613] R1 can be a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine.

[0614] R2 can be a methoxy group that is wholly or partially substituted with fluorine, and

[0615] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0616] For example, among them,

[0617] R1 can be C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, or benzoxy.

[0618] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0619] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0620] For example, among them,

[0621] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0622] R2 can be a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0623] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0624] For example, among them,

[0625] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0626] R2 can be C3-C5-cycloalkylmethoxy or benzylmethoxy, and

[0627] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0628] For example, among them,

[0629] R1 can be a difluoromethoxy group.

[0630] R2 can be methoxy, ethoxy, isopropoxy, isobutoxy, cyclopentoxy, cyclopropylmethoxy, cyclobutylmethoxy, difluoromethoxy, or 2,2,2-trifluoroethoxy, and R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, or 2,6-dimethylphenyl. Phenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl or 2,6-dichloropyridin-3-yl;

[0631] For example, among them,

[0632] R1 can be a difluoromethoxy group.

[0633] R2 can be methoxy, cyclopropylmethoxy, cyclobutylmethoxy, or difluoromethoxy, and

[0634] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0635] For example, among them,

[0636] R1 can be methoxy, n-propoxy, n-butoxy, cyclopropylmethoxy, or 2,2,2-trifluoroethoxy.

[0637] R2 can be difluoromethoxy, and

[0638] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0639] For example, among them,

[0640] R1 can be a difluoromethoxy group.

[0641] R2 can be cyclopropylmethoxy, and

[0642] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0643] For example, among them,

[0644] R1 can be a C3-C7-cycloalkoxy or a C3-C7-cycloalkylmethoxy, and R2 can be a C1-C4-alkoxy that is wholly or partially fluorinated; or R1 can be a C1-C4-alkoxy that is wholly or partially fluorinated, and R2 can be a C3-C7-cycloalkylmethoxy; and

[0645] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be hydroxyl, halogen, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, or C1-C4-alkylcarbonyloxy; R32 can be hydrogen, hydroxyl, halogen, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy; R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 can be hydroxyl, halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl; R35 can be hydrogen, halogen, amino or C1-C4-alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0646] For example, among them,

[0647] R1 can be C3-C7-cycloalkoxy or C3-C7-cycloalkylmethoxy.

[0648] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0649] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be hydroxyl, halogen, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, or C1-C4-alkylcarbonyloxy; R32 can be hydrogen, hydroxyl, halogen, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy; R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 can be hydroxyl, halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl; R35 can be hydrogen, halogen, amino or C1-C4-alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0650] For example, among them,

[0651] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0652] R2 can be C3-C7-cycloalkylmethoxy, and

[0653] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be hydroxyl, halogen, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl or C1-C4-alkylcarbonyloxy; R32 can be hydrogen, hydroxyl, halogen, trifluoromethyl, C1-C4-alkyl or C1-C4-alkoxy; R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy; R34 can be hydroxyl, halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl; R35 can be hydrogen, halogen or C1-C4-alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0654] For example, among them,

[0655] R1 can be C3-C5-cycloalkoxy or C3-C5-cycloalkylmethoxy.

[0656] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0657] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0658] For example, among them,

[0659] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0660] R2 can be C3-C5-cycloalkylmethoxy, and

[0661] R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33, or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen;

[0662] For example, among them,

[0663] R1 can be C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, or benzoxy.

[0664] R2 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and

[0665] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0666] For example, among them,

[0667] R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine.

[0668] R2 can be C3-C5-cycloalkylmethoxy, and

[0669] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0670] For example, among them,

[0671] R1 can be a difluoromethoxy group.

[0672] R2 can be cyclopropylmethoxy, and

[0673] R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl;

[0674] For example, R1 can be difluoromethoxy, R2 can be cyclopropylmethoxy, and R3 can be 3,5-dichloropyridin-4-yl.

[0675] For example, the PDE4 selective inhibitor or this application may comprise a compound of Formula I or a pharmaceutically acceptable salt thereof:

[0676]

[0677] For example, R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and R2 can be a methoxy group;

[0678] Or, for example, R1 can be hydrogen, C1-C6-alkoxy, C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine, and R2 can be a methoxy that is wholly or partially substituted with fluorine.

[0679] Or, for example, R1 can be a C3-C7-cycloalkoxy, C3-C7-cycloalkylmethoxy, or benzoxy, and R2 can be a C1-C4-alkoxy that is wholly or partially substituted with fluorine;

[0680] Or, for example, R1 may be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and R2 may be a C3-C7-cycloalkylmethoxy or benzoxy group;

[0681] And R3 can be phenyl, pyridyl, phenyl substituted with R31, R32 and R33, or pyridyl substituted with R34, R35, R36 and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, C1-C4-alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4-alkylamino or C1-C4-alkylcarbonylamino. R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4-alkyl, or C1-C4-alkoxy; R33 can be hydrogen, halogen, C1-C4-alkyl, or C1-C4-alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, or amino; R35 can be hydrogen, halogen, amino, or C1-C4-alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0682] For example, the PDE4 selective inhibitor or this application may comprise a compound of Formula I or a pharmaceutically acceptable salt thereof:

[0683]

[0684] For example, R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and R2 can be a methoxy group;

[0685] Or, for example, R1 can be a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine, and R2 can be a methoxy that is wholly or partially substituted with fluorine.

[0686] Or, for example, R1 can be a C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, or benzoxy, and R2 can be a C1-C4-alkoxy that is wholly or partially substituted with fluorine;

[0687] Or, for example, R1 may be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and R2 may be a C3-C5-cycloalkylmethoxy or benzoxy group;

[0688] And R3 can be phenyl, pyridyl, phenyl substituted by R31, R32 and R33 or pyridyl substituted by R34, R35, R36 and R37, wherein: R31 can be halogen, cyano, carboxyl, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkoxycarbonyl, R32 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R33 can be hydrogen, halogen, C1-C4-alkyl or C1-C4-alkoxy, R34 can be halogen or C1-C4-alkyl, R35 can be hydrogen or halogen, R36 can be hydrogen or halogen, and R37 can be hydrogen or halogen.

[0689] For example, the PDE4 selective inhibitor or this application may comprise a compound of Formula I or a pharmaceutically acceptable salt thereof:

[0690]

[0691] For example, R1 can be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and R2 can be a methoxy group;

[0692] Or, for example, R1 can be a C1-C4-alkoxy, C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, benzoxy, or a C1-C4-alkoxy that is wholly or partially substituted with fluorine, and R2 can be a methoxy that is wholly or partially substituted with fluorine.

[0693] Or, for example, R1 can be a C3-C5-cycloalkoxy, C3-C5-cycloalkylmethoxy, or benzoxy, and R2 can be a C1-C4-alkoxy that is wholly or partially substituted with fluorine;

[0694] Or, for example, R1 may be a C1-C4-alkoxy group that is wholly or partially substituted with fluorine, and R2 may be a C3-C5-cycloalkylmethoxy or benzoxy group;

[0695] And R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0696] For example, C1-C6-alkoxy groups can be hexyl, isohexyl (2-methylpentyl), neohexyl (2,2-dimethylbutyl), pentyl, isopentyl (3-methylbutyl), neopentyl (2,2-dimethylpropyl), butyl, isobutyl, sec-butyl, tert-butyl, propyl, isopropyl, ethyl, or methyl.

[0697] For example, C3-C7-cycloalkoxy can be cyclopropoxy, cyclobutoxy, cyclopentoxy, cyclohexyloxy, or cycloheptoxy.

[0698] For example, C3-C7-cycloalkylmethoxy can be cyclopropylmethoxy, cyclobutylmethoxy, cyclopentylmethoxy, cyclohexylmethoxy, or cycloheptylmethoxy.

[0699] For example, the C1-C4-alkoxy group that is wholly or partially substituted with fluorine can be 1,2,2-trifluoroethoxy, 2,2,3,3,3-pentafluoropropoxy, perfluoroethoxy, 1,1,2,2-tetrafluoroethoxy, trifluoromethoxy, 2,2,2-trifluoroethoxy, or difluoromethoxy.

[0700] For example, halogen can refer to bromine, chlorine, or fluorine.

[0701] For example, C1-C4-alkyl can refer to straight-chain or branched alkyl groups having 1 to 4 carbon atoms. Examples include butyl, isobutyl, sec-butyl, tert-butyl, propyl, isopropyl, ethyl, and methyl.

[0702] For example, C1-C4-alkoxy groups can be methoxy and ethoxy groups.

[0703] For example, C1-C4-alkoxycarbonyl can be methoxycarbonyl (CH3O-CO-) and ethoxycarbonyl (CH3CH2O-CO-).

[0704] For example, C1-C4-alkyl carbonyl can refer to an acetyl group (CH3CO-).

[0705] For example, the C1-C4-alkyl carbonyloxy group can be an acetic acid group (CH3CO-O-).

[0706] For example, the mono- or di-C1-C4-alkylamino group can be methylamino, dimethylamino, or diethylamino.

[0707] For example, the C1-C4-alkyl carbonyl amino group can be acetamino (-NH-CO-CH3).

[0708] For example, the phenyl groups substituted by R31, R32, and R33 can be selected from the group consisting of: 2-acetylphenyl, 2-aminophenyl, 2-bromophenyl, 2-chlorophenyl, 2,3-dichlorophenyl, 2,4-dichlorophenyl, 4-diethylamino-2-methylphenyl, 4-bromo-2-trifluoromethylphenyl, 2-carboxy-5-chlorophenyl, 3,5-dichloro-2-hydroxyphenyl, 2-bromo-4-carboxy-5-hydroxyphenyl, 2,6-dichlorophenyl, 2,5-di... Chlorophenyl, 2,4,6-trichlorophenyl, 2,4,6-trifluorophenyl, 2,6-dibromophenyl, 2-cyanophenyl, 4-cyano-2-fluorophenyl, 2-fluorophenyl, 2,4-difluorophenyl, 2,6-difluorophenyl, 2-chloro-6-fluorophenyl, 2-hydroxyphenyl, 2-hydroxy-4-methoxyphenyl, 2,4-dihydroxyphenyl, 2-methoxyphenyl, 2,3-dimethoxyphenyl, 2,4-dimethoxyphenyl, 2,6-dimethoxyphenyl 2-Dimethylaminophenyl, 2-methylphenyl, 2-chloro-6-methylphenyl, 2,4-dimethylphenyl, 2,6-dimethylphenyl, 2,3-dimethylphenyl, 2-methoxycarbonylphenyl, 2-trifluoromethylphenyl, 2,6-dichloro-4-methoxyphenyl, 2,6-dichloro-4-cyanophenyl, 2,6-dichloro-4-aminophenyl, 2,6-dichloro-4-methoxycarbonylphenyl, 4-acetamido-2,6-dichlorophenyl and 2,6-dichloro-4-ethoxycarbonylphenyl.

[0709] For example, the pyridine group substituted by R34, R35, R36, and R37 can be a group selected from the group consisting of: 3,5-dichloropyridin-4-yl, 2,6-diaminopyridin-3-yl, 4-aminopyridin-3-yl, 3-methylpyridin-2-yl, 4-methylpyridin-2-yl, 5-hydroxypyridin-2-yl, 4-chloropyridin-3-yl, 3-chloropyridin-2-yl, 3-chloropyridin-4-yl, and 2-chloropyridine. -3-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, 3,5-dibromopyridin-2-yl, 3,5-dibromopyridin-4-yl, 3,5-dichloropyridin-4-yl, 2,6-dichloropyridin-3-yl, 3,5-dimethylpyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl and 2,3,5-trifluoropyridin-4-yl.

[0710] For example, the PDE4 selective inhibitor or the compound of this application may comprise a compound of Formula I or a pharmaceutically acceptable salt thereof:

[0711]

[0712] Wherein, one of R1 and R2 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy that is wholly or partially substituted with fluorine, and the other of R1 and R2 can be a C1-C4 alkoxy that is wholly or partially substituted with fluorine.

[0713] R3 can be phenyl, pyridyl, a phenyl group substituted with R31, R32, and R33, or a pyridyl group substituted with R34, R35, R36, and R37, wherein:

[0714] R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino or C1-C4 alkylcarbonylamino.

[0715] R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl, or C1-C4 alkoxy.

[0716] R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy.

[0717] R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, or amino; R35 can be hydrogen, halogen, amino, or C1-C4 alkyl.

[0718] R36 can be hydrogen or halogen, and

[0719] R37 can be hydrogen or halogen.

[0720] For example, the PDE4 selective inhibitor or this application may contain Roflumilast or a derivative thereof.

[0721] For example, the derivatives of the Roflumilast may include benzamide, bezafibrate, and / or 4-Methylbenzanilide.

[0722] For example, the compound having the structure shown in Formula I may comprise the compound described in patent application (US5712298A), which is incorporated herein by reference.

[0723] For example, in formula I: R1 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy that is wholly or partially substituted with fluorine.

[0724] R2 can be a C1-C4 alkoxy group that is wholly or partially substituted with fluorine, and

[0725] R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein:

[0726] R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino or C1-C4 alkylcarbonylamino; R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl or amino; R35 can be hydrogen, halogen, amino or C1-C4 alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0727] For example, in Formula I: R1 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy group wholly or partially substituted with fluorine; R2 can be a methoxy group wholly or partially substituted with fluorine; and R3 can be phenyl, pyridyl, phenyl group substituted with R31, R32, and R33, or pyridyl group substituted with R34, R35, R36, and R37, wherein: R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, or C1-C4 alkylcarbonyl. R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxy carbonyl, or amino; R35 can be hydrogen, halogen, amino, or C1-C4 alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0728] For example, in Formula I: R1 can be a C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, or benzoxy; R2 can be a C1-C4 alkoxy that is wholly or partially substituted with fluorine; and R3 can be phenyl, pyridyl, a phenyl substituted with R31, R32, and R33, or a pyridyl substituted with R34, R35, R36, and R37, wherein:

[0729] R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino or C1-C4 alkylcarbonylamino; R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl or amino; R35 can be hydrogen, halogen, amino or C1-C4 alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0730] For example, in Formula I: R1 can be a C1-C4 alkoxy group that is wholly or partially substituted with fluorine; R2 can be hydrogen, C1-C6 alkoxy, C3-C7 cycloalkoxy, C3-C7 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy group that is wholly or partially substituted with fluorine; and R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein:

[0731] R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4-alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino or C1-C4 alkylcarbonylamino; R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, 1-4C-alkyl, 1-4C-alkoxy, C1-C4 alkoxycarbonyl or amino; R35 can be hydrogen, halogen, amino or 1-4C-alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0732] For example, in Formula I: R1 can be a C1-C4 alkoxy group that is wholly or partially substituted with fluorine, R2 can be a C3-C7 cycloalkylmethoxy group or benzoxy group, and R3 can be a phenyl group, a pyridyl group, a phenyl group substituted with R31, R32 and R33, or a pyridyl group substituted with R34, R35, R36 and R37, wherein:

[0733] R31 can be hydroxyl, halogen, cyano, carboxyl, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl, C1-C4 alkylcarbonyl, C1-C4 alkylcarbonyloxy, amino, mono- or di-C1-C4 alkylamino or C1-C4 alkylcarbonylamino; R32 can be hydrogen, hydroxyl, halogen, amino, trifluoromethyl, C1-C4 alkyl or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl or C1-C4 alkoxy; R34 can be hydroxyl, halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkoxycarbonyl or amino; R35 can be hydrogen, halogen, amino or C1-C4 alkyl; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0734] For example, in Formula I: R1 can be a C1-C4 alkoxy, C3-C5 cycloalkoxy, C3-C5 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy wholly or partially substituted with fluorine; R2 can be a C1-C4 alkoxy wholly or partially substituted with fluorine; and R3 can be phenyl, pyridyl, phenyl substituted with R31, R32, and R33, or pyridyl substituted with R34, R35, R36, and R37, wherein:

[0735] R31 can be halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, or C1-C4 alkoxycarbonyl; R32 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be halogen or C1-C4 alkyl; R35 can be hydrogen or halogen; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0736] For example, in Formula I: R1 can be a C1-C4 alkoxy, C3-C5 cycloalkoxy, C3-C5 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy wholly or partially substituted with fluorine; R2 can be a methoxy wholly or partially substituted with fluorine; and R3 can be phenyl, pyridyl, a phenyl substituted with R31, R32, and R33, or a pyridyl substituted with R34, R35, R36, and R37, wherein:

[0737] R31 can be halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, or C1-C4 alkoxycarbonyl; R32 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be halogen or C1-C4 alkyl; R35 can be hydrogen or halogen; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0738] For example, in Formula I: R1 can be a C3-C5 cycloalkoxy, C3-C5 cycloalkylmethoxy, or benzoxy; R2 can be a C1-C4 alkoxy that is wholly or partially substituted with fluorine; and R3 can be phenyl, pyridyl, a phenyl substituted with R31, R32, and R33, or a pyridyl substituted with R34, R35, R36, and R37, wherein:

[0739] R31 can be halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, or C1-C4 alkoxycarbonyl; R32 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be halogen or C1-C4 alkyl; R35 can be hydrogen or halogen; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0740] For example, in Formula I: R1 can be a C1-C4 alkoxy group that is wholly or partially substituted with fluorine; R2 can be a C1-C4 alkoxy group, a C3-C5 cycloalkoxy group, a C3-C5 cycloalkylmethoxy group, a benzoxy group, or a C1-C4 alkoxy group that is wholly or partially substituted with fluorine; and R3 can be a phenyl group, a pyridyl group, a phenyl group substituted with R31, R32, and R33, or a pyridyl group substituted with R34, R35, R36, and R37, wherein:

[0741] R31 can be halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, or C1-C4 alkoxycarbonyl; R32 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be halogen or C1-C4 alkyl; R35 can be hydrogen or halogen; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0742] For example, in Formula I: R1 can be a C1-C4 alkoxy group that is wholly or partially substituted with fluorine, R2 can be a C3-C5 cycloalkylmethoxy group or benzoxy group, and R3 can be a phenyl group, a pyridyl group, a phenyl group substituted with R31, R32 and R33, or a pyridyl group substituted with R34, R35, R36 and R37, wherein:

[0743] R31 can be halogen, cyano, carboxyl, C1-C4 alkyl, C1-C4 alkoxy, or C1-C4 alkoxycarbonyl; R32 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R33 can be hydrogen, halogen, C1-C4 alkyl, or C1-C4 alkoxy; R34 can be halogen or C1-C4 alkyl; R35 can be hydrogen or halogen; R36 can be hydrogen or halogen; and R37 can be hydrogen or halogen.

[0744] For example, in Formula I: R1 can be a C1-C4 alkoxy, C1-C4 cycloalkoxy, C1-C4 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy wholly or partially substituted with fluorine; R2 can be a C1-C4 alkoxy wholly or partially substituted with fluorine; and R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro- 6-Methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0745] For example, in Formula I: R1 can be a C1-C4 alkoxy, C3-C5 cycloalkoxy, C3-C5 cycloalkylmethoxy, benzoxy, or a C1-C4 alkoxy wholly or partially substituted with fluorine; R2 can be a methoxy wholly or partially substituted with fluorine; and R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6- Methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0746] For example, in Formula I: R1 can be a C3-C5 cycloalkoxy, C3-C5 cycloalkylmethoxy, or benzoxy; R2 can be a C1-C4 alkoxy that is wholly or partially substituted with fluorine; and R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, or 2,6-dimethylphenyl. Phenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0747] For example, in Formula I: R1 can be a C1-C4 alkoxy group that is wholly or partially substituted with fluorine; R2 can be a C1-C4 alkoxy group, a C3-C5 cycloalkoxy group, a C3-C5 cycloalkylmethoxy group, a benzoxy group, or a C1-C4 alkoxy group that is wholly or partially substituted with fluorine; and R3 can be a 2-bromophenyl group, a 2,6-dichloro-4-ethoxycarbonylphenyl group, a 2,6-dimethoxyphenyl group, a 4-cyano-2-fluorophenyl group, a 2,4,6-trifluorophenyl group, a 2-chloro- 6-Methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0748] For example, in Formula I: R1 can be a C1-C4 alkoxy group that is wholly or partially substituted with fluorine, R2 can be a C3-C5 cycloalkylmethoxy or benzylmethoxy group, and R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2, 6-Difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0749] For example, in Formula I: R1 can be difluoromethoxy, R2 can be methoxy, ethoxy, isopropoxy, isobutoxy, cyclopentoxy, cyclopropylmethoxy, cyclobutylmethoxy, difluoromethoxy, or 2,2,2-trifluoroethoxy, and R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, or 2-chloro-6-methylphenyl. 2,6-Dimethylphenyl, 2,6-Difluorophenyl, 2,6-Dichlorophenyl, 3,5-Dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-Dibromopyridin-2-yl, 2,3,5,6-Tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl or 2,6-dichloropyridin-3-yl.

[0750] For example, in Formula I: R1 can be difluoromethoxy, R2 can be methoxy, cyclopropylmethoxy, cyclobutylmethoxy, or difluoromethoxy, and R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6- Difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0751] For example, in Formula I: R1 can be methoxy, n-propoxy, n-butoxy, cyclopropylmethoxy, or 2,2,2-trifluoroethoxy; R2 can be difluoromethoxy; and R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, or 2,6-dimethylphenyl. 2,6-Difluorophenyl, 2,6-Dichlorophenyl, 3,5-Dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl or 2,6-dichloropyridin-3-yl.

[0752] For example, in Formula I: R1 can be difluoromethoxy, R2 can be cyclopropylmethoxy, and R3 can be 2-bromophenyl, 2,6-dichloro-4-ethoxycarbonylphenyl, 2,6-dimethoxyphenyl, 4-cyano-2-fluorophenyl, 2,4,6-trifluorophenyl, 2-chloro-6-methylphenyl, 2,6-dimethylphenyl, 2,6-difluorophenyl, 2,6-dichlorophenyl, 3,5-dichloropyridin-4-yl, 3-methylpyridin-2-yl, 2-chloropyridin-3-yl, 3,5-dibromopyridin-2-yl, 2,3,5,6-tetrafluoropyridin-4-yl, 3-chloro-2,5,6-trifluoropyridin-4-yl, 3,5-dichloro-2,6-difluoropyridin-4-yl, or 2,6-dichloropyridin-3-yl.

[0753] For example, the compounds having the structure of Formula I may include N-(3,5-dichloropyridin-4-yl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 170°C), N-(3,5-dichloropyridin-4-yl)-3,4-bis-difluoromethoxybenzamide (melting point: 134°C), N-(3,5-dichloropyridin-4-yl)-3-cyclobutylmethoxy-4-difluoromethoxybenzamide (melting point: 155°C), N-(3,5-di-... N-(3,5-dichloropyridin-4-yl)-3-cyclopentoxy-4-difluoromethoxybenzamide (melting point: 128.5~129℃), N-(3,5-dichloropyridin-4-yl)-3-cyclopropylmethoxy-4-difluoromethoxybenzamide (melting point: 158℃), N-(3,5-dichloro-2,6-difluoropyridin-4-yl)-3-difluoromethoxy-4-methoxybenzamide (melting point: 218℃), N-(2,6-dichlorophenyl)-3-difluoro N-(2,6-dimethylphenyl)-3-difluoromethoxy-4-methoxybenzamide (melting point: 164℃), N-(2,6-dimethylphenyl)-3-difluoromethoxy-4-methoxybenzamide (melting point: 164℃), N-(2-chloropyridin-3-yl)-3-difluoromethoxy-4-methoxybenzamide (melting point: 165℃), N-(3,5-dibromopyridin-2-yl)-3-difluoromethoxy-4-methoxybenzamide (melting point: 143℃), N-(3,5-dichloropyridin-2-yl)-3-difluoromethoxy-4-methoxybenzamide (melting point: 143℃), N-(3,5-dichloropyridin-2-yl)-3-difluoromethoxy-4-methoxybenzamide (melting point: 143℃), N-(3,5-dichloropyridin-4-yl)-3-difluoromethoxy-4-methoxybenzamide (melting point: 178℃), N-(3,5-dichloropyridin-4-yl)-3-difluoromethoxy-4-propoxybenzamide (melting point: 159℃), N-(3,5-dichloropyridin-4-yl)-3-ethoxy-4-difluoromethoxybenzamide (melting point: 134℃), N-(3,5-dichloropyridin-4-yl)benzoxy-3-difluoromethoxybenzamide (melting point: 1... N-(3,5-dichloropyridin-4-yl)-4-butoxy-3-difluoromethoxybenzamide (melting point: 146℃), N-(3,5-dichloropyridin-4-yl)-4-cyclopropylmethoxy-3-difluoromethoxybenzamide (melting point: 159℃), N-(3,5-dichloropyridin-4-yl)-4-difluoromethoxy-3-(1-methylethoxy)benzamide (melting point: 99℃).N-(3,5-dichloropyridin-4-yl)-4-difluoromethoxy-3-(2,2,2-trifluoroethoxy)-benzamide (melting point: 147℃), N-(3,5-dichloropyridin-4-yl)-4-difluoromethoxy-3-(2-methylpropoxy)benzamide (melting point: 153℃), N-(2,3,5,6-tetrafluoropyridin-4-yl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 146℃), N-(2,4,6-trifluorophenyl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 146℃), N-(2,4,6-trifluorophenyl)-4-difluoromethoxy-3-(2,2,2-trifluoroethoxy)-4-difluoromethoxy-3-(2,2,2-trifluoroethoxy)-4-difluoromethoxy-3-(2,5-dichloropyridin-4-yl)-4-difluoromethoxy-3-(2-methylpropoxy)benzamide (melting point: 153℃), N-(2,3,5,6-tetrafluoropyridin-4-yl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 146℃), N-(2,4,6-trifluorophenyl)-4-difluoromethoxy-3-(2,2,2-trifluoroethoxy)-4-difluoromethoxy-3-(2,2,2-trifluoroethoxy)-3-(2,4,6-trifluorophenyl)-4-difluoromethoxy-3-(2,2,2-trifluoroethoxy)-3-(2,5-dichloropyridin-4-yl)-4-difluoromethoxy-3-(2,2,2-trifluoroethoxy)-3-(2,5-dichloropyridin-4-yl)-4-difluoromethoxy-3- 3-Methoxybenzamide (melting point: 145℃), N-(2,6-dichloro-4-ethoxycarbonylphenyl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 176℃), N-(2,6-dichlorophenyl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 186℃), N-(2,6-difluorophenyl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 139℃), N-(2,6-dimethylphenyl)-4-difluoromethoxy-3-methoxybenzamide Amide (melting point: 143℃), N-(2-bromophenyl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 121℃), N-(2-chloro-6-methylphenyl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 144℃), N-(2-chloropyridin-3-yl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 137.5℃), N-(2-methylphenyl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 125℃), N-(3,5-di... N-(3,5-dichloro-2,6-difluoropyridin-4-yl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 141℃), N-(3,5-dichloro-2,6-difluoropyridin-4-yl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 174℃), N-(3-chloro-2,5,6-trifluoropyridin-4-yl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 141℃), N-(3-methylpyridin-2-yl)-4-difluoromethoxy-3-methoxybenzamide (melting point: 96℃).

[0754] For example, a suitable salt of a compound of formula I can be any acid addition salt or any salt formed with a base, depending on the substitution reaction. Of particular note are salts that are pharmacologically tolerable and generally used in pharmaceutical preparations of inorganic and organic acids and bases. Pharmacologically intolerant salts, for example, can be initially precipitated as intermediates on an industrial scale during the preparation of the compounds described in this application, and then converted into pharmacologically tolerable salts using methods familiar to those skilled in the art. On one hand, the suitable salt can be an acid addition salt that forms both water-soluble and water-insoluble forms with an acid, such as an acid suitable for this purpose. Here, in preparing the salt, the acid used can be monobasic or polybasic, and the dosage ratio can be molar or deviate from that molar ratio, depending on the type of salt being prepared.

[0755] For example, it can also react with a base to form a salt. Examples of basic salts include suitable salts, where, in the preparation of the salt, the base can be added in a molar amount or a proportion deviating from that amount.

[0756] Immune checkpoint inhibitors

[0757] On the one hand, the immune checkpoint inhibitors of this application may include antagonists of one or more of the following proteins: CTLA-4, PD-1, PD-L1, PD-L2, LAG-3, TIM-3, galactoglobulin 9, CEACAM-1, BTLA, CD69, galactoglobulin-1, TIGIT, CD113, GPR56, VISTA, 2B4, CD48, GARP, PD1H, LAIR1, TIM-1, and TIM-4.

[0758] For example, the immune checkpoint inhibitor of this application may include PD-1 and / or PD-L1 antagonists.

[0759] For example, the PD-1 and / or PD-L1 antagonists of this application can inhibit the interaction between PD-1 and PD-L1.

[0760] For example, the PD-1 and / or PD-L1 antagonists of this application may include antibodies or antigen-binding fragments thereof that specifically bind to PD-1 and / or PD-L1.

[0761] For example, the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain HCDR3, and HCDR3 may contain the amino acid sequence shown in any one of SEQ ID NO: 3, 13, 23, and 33. For example, the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain HCDR2, and HCDR2 may contain the amino acid sequence shown in any one of SEQ ID NO: 2, 12, 22, and 32. For example, the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain HCDR1, and HCDR1 may contain the amino acid sequence shown in any one of SEQ ID NO: 1, 11, 21, and 31. For example, the CDR of the antibody in this application may be partitioned according to the Kabat scheme.

[0762] For example, the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain HCDR3, which may contain the amino acid sequence shown in any one of SEQ ID NO: 3, 13, 23, and 33; the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain HCDR2, which may contain the amino acid sequence shown in any one of SEQ ID NO: 2, 12, 22, and 32; and the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain HCDR1, which may contain the amino acid sequence shown in any one of SEQ ID NO: 1, 11, 21, and 31. For example, the CDR of the antibody in this application may be determined according to the Kabat scheme.

[0763] For example, the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain LCDR3, and LCDR3 may contain the amino acid sequence shown in any one of SEQ ID NO: 6, 16, 26, and 36. For example, the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain LCDR2, and LCDR2 may contain the amino acid sequence shown in any one of SEQ ID NO: 5, 15, 25, and 35. For example, the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain LCDR1, and LCDR1 may contain the amino acid sequence shown in any one of SEQ ID NO: 4, 14, 24, and 34. For example, the CDR of the antibody in this application may be partitioned according to the Kabat scheme.

[0764] For example, the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain LCDR3, which may contain the amino acid sequence shown in any one of SEQ ID NO: 6, 16, 26, and 36; the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain LCDR2, which may contain the amino acid sequence shown in any one of SEQ ID NO: 5, 15, 25, and 35; and the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain LCDR1, which may contain the amino acid sequence shown in any one of SEQ ID NO: 4, 14, 24, and 34. For example, the CDR of the antibody in this application may be determined according to the Kabat scheme.

[0765] For example, the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain HCDR3, which may contain the amino acid sequence shown in any one of SEQ ID NO: 3, 13, 23, and 33, and the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain LCDR3, which may contain the amino acid sequence shown in any one of SEQ ID NO: 6, 16, 26, and 36. For example, the CDR of the antibody in this application may be determined according to the Kabat scheme.

[0766] For example, the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain HCDR3, which may contain the amino acid sequence shown in any one of SEQ ID NO: 3, 13, 23, and 33; the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain HCDR2, which may contain the amino acid sequence shown in any one of SEQ ID NO: 2, 12, 22, and 32; the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain HCDR1, which may contain the amino acid sequence shown in any one of SEQ ID NO: 1, 11, 21, and 31; the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain LCDR3, which may contain the amino acid sequence shown in any one of SEQ ID NO: 6, 16, 26, and 36; the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain LCDR2, which may contain the amino acid sequence shown in SEQ ID NO: 3, 13, 23, and 33. The amino acid sequence shown in any one of SEQ ID NO: 5, 15, 25, and 35, and the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain LCDR1, and the LCDR1 may contain the amino acid sequence shown in any one of SEQ ID NO: 4, 14, 24, and 34. For example, the CDR of the antibody of this application may be partitioned according to the Kabat scheme.

[0767] For example, the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain a VH, and the VH may contain the amino acid sequence shown in any one of SEQ ID NO: 7, 17, 27, and 37. For example, the antibody or its antigen-binding fragment that specifically binds to PD-1 and / or PD-L1 may contain a VL, and the VL may contain the amino acid sequence shown in any one of SEQ ID NO: 4, 14, 24, and 34. For example, the CDR of the antibody in this application may be partitioned according to the Kabat scheme.

[0768] For example, the antibody that specifically binds to PD-1 and / or PD-L1 or its antigen-binding fragment may contain VH, which may contain the amino acid sequence shown in any one of SEQ ID NO: 7, 17, 27 and 37; the antibody that specifically binds to PD-1 and / or PD-L1 or its antigen-binding fragment may contain VL, which may contain the amino acid sequence shown in any one of SEQ ID NO: 4, 14, 24 and 34.

[0769] For example, the antibody or antigen-binding fragment thereof that specifically binds to PD-1 and / or PD-L1 may comprise a heavy chain, and the heavy chain may comprise the amino acid sequence shown in any one of SEQ ID NO: 9, 19, 29, and 39. For example, the antibody or antigen-binding fragment thereof that specifically binds to PD-1 and / or PD-L1 may comprise a light chain, and the light chain may comprise the amino acid sequence shown in any one of SEQ ID NO: 10, 20, 30, and 40.

[0770] For example, the antibody that specifically binds to PD-1 and / or PD-L1 or its antigen-binding fragment may contain a heavy chain, which may contain the amino acid sequence shown in any one of SEQ ID NO: 9, 19, 29 and 39. The antibody that specifically binds to PD-1 and / or PD-L1 or its antigen-binding fragment may contain a light chain, which may contain the amino acid sequence shown in any one of SEQ ID NO: 10, 20, 30 and 40.

[0771] For example, the antibody may be selected from chimeric antibodies, humanized antibodies, and fully human antibodies.

[0772] For example, the antigen-binding fragment may be selected from: Fab, Fv, scFv, Fab' and (Fab')2.

[0773] For example, the antibody that specifically binds to PD-1 and / or PD-L1 in this application may include:

[0774] HCDR1-3 and LCDR1-3 of nivolumab (Opdivo or Nivolumab)

[0775] HCDR1-3 and LCDR1-3 of pembrolizumab (Keytruda or Pembrolizumab)

[0776] Toripalimab (JS-001, CAS#:1924598-82-2) HCDR1-3 and LCDR1-3

[0777] Sintilimab (IBI308, CAS#:2072873-06-2) HCDR1-3 and LCDR1-3,

[0778] Camrelizumab (SHR-1210, CAS#:1798286-48-2) HCDR1-3 and LCDR1-3

[0779] HCDR1-3 and LCDR1-3 of BMS-936559 (MDX-1105);

[0780] MPDL3280A (Tecentriq or Atezolizumab) HCDR1-3 and LCDR1-3;

[0781] MEDI4736 (Imfinzi or Durvalumab) HCDR1-3 and LCDR1-3; or

[0782] MSB0010718C (Avelumab) HCDR1-3 and LCDR1-3; for example, the CDR of the antibody in this application may be determined according to the Kabat scheme; for example, the CDR of the antibody in this application may be determined according to the Chothia scheme; for example, the CDR of the antibody in this application may be determined according to the IMGT scheme.

[0783] For example, the antibody that specifically binds to PD-1 and / or PD-L1 in this application may include:

[0784] Nivolumab's VH and VL,

[0785] Pembrolizumab in VH and VL,

[0786] BMS-936559's VH and VL;

[0787] VH and VL of MPDL3280A;

[0788] MEDI4736's VH and VL; or

[0789] VH and VL in MSB0010718C.

[0790] For example, the antibodies that specifically bind to PD-1 and / or PD-L1 in this application can be selected from: nivolumab, pembrolizumab, BMS-936559 (BMS-936559 can also be called 12A4 or MDX-1105. A description of BMS-936559 can be found in US Patent No. 7,943,743 or WO2013 / 173223A1), MPDL3280A (also called RG7446 or atezolizumab. A description of MPDL3280A can be found in Herbst et al. (2013) J Clin Oncol 31(suppl):3000.Abstract. or US Patent No. 8,217,149), MEDI4736 (also called Durvalumab. A description of MEDI4736 can be found in Khleif (2013) In: Proceedings from the European Cancer Congress). 2013; September 27 – October 1, 2013; Amsterdam, The Netherlands), AMP-224 (which may be a B7-DC Fc fusion protein. The description of AMP-224 can be found in US Publication No. US2013 / 0017199A1) and MSB0010718C (which may also be called Avelumab. The description of MSB0010718C can be found in US 2014 / 0341917A1).

[0791] Carriers and formulations

[0792] The PDE4 selective inhibitor and the immune checkpoint inhibitor of this application can be prepared as independent formulations (i.e., the first formulation, the second formulation, and the third formulation), or they can be prepared as a combination of suitable formulations, such as the PDE4 selective inhibitor and the immune checkpoint inhibitor of this application. Whether prepared independently or as a combination, they can be combined with any suitable carrier to obtain the desired formulation type.

[0793] For example, the dosage form of the first formulation, the second formulation, or the pharmaceutical composition may include tablets, capsules, granules, powders, syrups, suspensions, suppositories, ointments, creams, gels, patches, inhalers, injections, etc. These formulations can be prepared according to conventional methods.

[0794] For example, when it is a liquid formulation, it can be in the form of being dissolved or suspended in water or other suitable solvents at the time of use.

[0795] For example, tablets and granules can be coated using known methods.

[0796] For example, in the case of an injectable preparation, the active ingredient (including the PDE4 selective inhibitor and / or the immune checkpoint inhibitor of this application) can be dissolved in water for preparation, or dissolved in physiological saline or glucose solution as needed, and buffers and preservatives can be added.

[0797] For example, it can be provided in any formulation form, whether for oral or non-oral administration. For example, it can be prepared as an oral formulation in the form of granules, fine granules, powders, hard capsules, soft capsules, syrups, emulsions, suspensions, or liquids.

[0798] For example, it can also be a non-oral preparation in the form of injections, drops, transdermal absorption agents, transmucosal absorption agents, nasal drops, inhalants, suppositories, etc., for intravenous administration, intramuscular administration, intradermal administration, intracavitary administration, intratumoral administration, peritumoral administration, or subcutaneous administration.

[0799] For example, injections and infusions can be prepared into lyophilized powder forms, which are then dissolved in suitable aqueous media such as physiological saline before use.

[0800] For example, sustained-release formulations coated with polymers or similar materials can be directly administered to organs, tissues, or tumors such as the brain, blood, and lymph nodes. For instance, the sustained-release formulation may include a sustained-release pump, a sustained-release capsule, a sustained-release agent, an implant, or a sustained-release implant.

[0801] Regarding the type of formulation additive (carrier) used in the manufacture of pharmaceutical preparations, the ratio of the formulation additive (carrier) to the active ingredient, or the manufacturing method of the preparation, those skilled in the art can appropriately select the appropriate additive based on the form of the preparation. For example, as a formulation additive (carrier), inorganic or organic substances, or solid or liquid substances, can be used, for example, in a proportion between 1% and 90% by weight relative to the active ingredient.

[0802] For example, in manufacturing oral solid dosage forms, the active ingredient (including the PDE4 selective inhibitor and / or the immune checkpoint inhibitor of this application) can be mixed with a carrier component to form a powder; for example, granules can be added as needed; for example, in manufacturing tablets, the powder and / or granules can be directly compressed; for example, a lubricant can be added for compression; for example, the granules or tablets can be coated with an enteric-coated matrix such as a polymer to form an enteric-coated formulation; for example, a long-acting formulation can be formed by coating; for example, in manufacturing capsules, the powder or granules can be filled into a hard capsule; for example, the active ingredient can be directly or dissolved in a solvent and then covered with a gelatin film to form a soft capsule.

[0803] For example, in the manufacture of injectables, the active ingredient and desired substances can be dissolved together in distilled water for injection as needed; for example, it can be further sterile filtered and filled into ampoules; for example, desired substances can be added and vacuum freeze-dried to produce a dissolving-on-use injectable. For example, desired substances can be added to the active ingredient and emulsified in water to produce an emulsion for injection.

[0804] For example, in the manufacture of rectal medications, the active ingredient can be humidified and dissolved together with a suppository substrate and then flowed into a mold for cooling. Alternatively, the active ingredient can be dissolved in a desired substance and then coated with a gelatin film.

[0805] For example, in the manufacture of topical skin preparations, the active ingredient can be added to the desired substance, moistened and kneaded as needed to form an ointment; or it can be kneaded with the desired substance or other adhesive and then stretched onto a nonwoven fabric such as a polyalkylene compound to form a strip preparation.

[0806] For example, it can also be used as a sustained-release formulation, such as an implantable tablet or a delivery system encapsulated in microcapsules, which can be prepared using a carrier that prevents immediate removal from the body. For example, the desired substance can be used. Those skilled in the art can readily prepare these materials. For example, suspensions of liposomes can also be used as pharmaceutically acceptable carriers. The liposomes can contain the desired substance, can be prepared by means of a suitable size for use, by passing through a filter of appropriate pore size, and by purification via reverse-phase evaporation.

[0807] In this application, the dosage and frequency of administration can be appropriately selected based on the purpose of prevention and / or treatment of the disease progression in the treatment subject (subject), the type of disease, the patient's weight, age, and other conditions. For example, when administered orally, it can be divided into appropriate doses or administered every few days. When used as an injectable preparation, it can be administered continuously or intermittently.

[0808] The embodiments described below are not intended to be limited by any theory, but are merely for illustrating the drug combinations, methods of use, and applications of this application, and are not intended to limit the scope of the invention.

[0809] Example

[0810] Example 1: Roflumilast can inhibit tumor metastasis.

[0811] C57 mice used in this application were purchased from Vital River Laboratory Animal Technology Co., Ltd.; MC38 cells were purchased from ATCC; Roflumilast was purchased from Aladdin (catalog number: R126602); and oxaliplatin was purchased from Aladdin (catalog number: O124003). DMSO was used as the solvent for both oxaliplatin and Roflumilast.

[0812] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were selected, and MC38 cells were cultured in vitro to the logarithmic growth phase. The cells were collected and resuspended in PBS buffer. The collected cells were surgically injected into the spleen of the mice, with each mouse receiving 5 × 10⁶ cells. 5 MC38 cells were used to establish a tumor metastasis model.

[0813] (2) After modeling, mice were divided into three experimental groups: a blank control group, a Roflumilast group, and an oxaliplatin group. Mice in the Roflumilast group were injected intraperitoneally with 4 mg / kg of Roflumilast every 3 days for a total of 6 times; simultaneously, mice in the oxaliplatin group were injected with 4 mg / kg of oxaliplatin for a total of 6 times; the blank control group was injected with the same volume of physiological saline. Day 1 was the day of the first injection. Afterwards, the weight of the mice was recorded, and Luciferin fluorescence imaging was performed on the mice. Specifically, 100 μL of a 1 mg / mL D-fluorescein potassium aqueous solution was injected intraperitoneally into each mouse. Ten minutes after injection, Luciferin fluorescence imaging was performed using a small animal in vivo imaging system (model: IVIS Lumina XRMS Series III).

[0814] like Figure 1 A and Figure 1 As shown in the results, the PDE4 selective inhibitor of this application can inhibit tumor metastasis and / or has good safety.

[0815] Example 2: PDE4 selective inhibitors can synergistically inhibit tumor growth with immune checkpoint inhibitors.

[0816] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were selected, and MC38 cells were cultured in vitro to the logarithmic growth phase. The cells were collected and resuspended in PBS buffer. The collected cells were injected subcutaneously into the legs of the mice, with each mouse receiving 5 × 10⁶ cells. 5 MC38 cells were used to establish a subcutaneous tumor model.

[0817] (2) After tumor formation, mice were divided into four experimental groups: blank control, Roflumilast group, immune checkpoint inhibitor group, and Roflumilast + immune checkpoint inhibitor group. Every 3 days, mice in the Roflumilast + immune checkpoint inhibitor group were intraperitoneally injected with 4 mg / kg of Roflumilast and 2 mg / kg of immune checkpoint inhibitor (e.g., PD-L1 antibody, such as MPDL3280A, MEDI4736, or MSB0010718C), for a total of 6 administrations. Simultaneously, the Roflumilast group and immune checkpoint inhibitor group were injected separately with the same dose of Roflumilast and immune checkpoint inhibitor, respectively, in the same manner. The blank control group was injected with the same dose of physiological saline. Day 1 was the day of the first injection. Afterwards, the mouse's body weight and tumor size were recorded: tumor volume (mm). 3 = Length (L) × Width (W) 2 / 2, and Luciferin fluorescence imaging was performed on the tumors, i.e., 100 μL of 1 mg / mL D-fluorescein potassium aqueous solution was prepared and injected intraperitoneally into each mouse. 10 min after injection, Luciferin fluorescence imaging was performed on the tumors using a small animal in vivo imaging system (model: IVIS Lumina XRMS Series III).

[0818] like Figure 2 A, Figure 2 B and Figure 2 As shown in the results, the combination of the PDE4 selective inhibitor and the immune checkpoint inhibitor in this application can inhibit tumor growth, and the two have a synergistic effect and / or good safety.

[0819] 2.1 Roflumilast and anti-PD-L1 antibody synergistically inhibit colon cancer growth

[0820] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were used to culture colon cancer cells, such as MC38 cells, in vitro. After reaching the logarithmic growth phase, the cells were collected and resuspended in PBS buffer. The collected cells were injected subcutaneously into the legs of the mice, with each mouse receiving 5 × 10⁶ cells. 5 Cells were used to establish a subcutaneous tumor model.

[0821] (2) After tumor formation, mice were divided into four experimental groups: a blank control group, a PDE4 inhibitor group, an immune checkpoint inhibitor group, and a PDE4 inhibitor + immune checkpoint inhibitor group. Every 3 days, mice receiving the PDE4 inhibitor + immune checkpoint inhibitor group were intraperitoneally injected with, for example, 4 mg / kg of PDE4 inhibitor and, for example, 2 mg / kg of immune checkpoint inhibitor (e.g., PD-L1 antibody), for a total of 6 administrations. Simultaneously, the PDE4 inhibitor group and the immune checkpoint inhibitor group were injected separately with the same dose of PDE4 inhibitor and immune checkpoint inhibitor, respectively, in the same manner. The blank control group was injected with the same dose of physiological saline. Day 1 was defined as the day of the first injection. Afterwards, the mice's body weight and tumor size were recorded: tumor volume (mm). 3 = Length (L) × Width (W) 2 / 2, and Luciferin fluorescence imaging was performed on the tumors, i.e., 100 μL of 1 mg / mL D-fluorescein potassium aqueous solution was prepared and injected intraperitoneally into each mouse. 10 min after injection, Luciferin fluorescence imaging was performed on the tumors using a small animal in vivo imaging system (model: IVIS Lumina XRMS Series III).

[0822] The results show that the combination of the PDE4 selective inhibitor and the immune checkpoint inhibitor in this application can inhibit tumor growth, and the two have a synergistic effect and / or good safety.

[0823] 2.2 Roflumilast and anti-PD-L1 antibody synergistically inhibit breast cancer growth

[0824] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were used to culture breast cancer cells in vitro to the logarithmic growth phase. The cells were collected and resuspended in PBS buffer. The collected cells were injected subcutaneously into the legs of the mice, with each mouse receiving 5 × 10⁶ cells. 5 Cells were used to establish a subcutaneous tumor model.

[0825] (2) After tumor formation, mice were divided into four experimental groups: a blank control group, a PDE4 inhibitor group, an immune checkpoint inhibitor group, and a PDE4 inhibitor + immune checkpoint inhibitor group. Every 3 days, mice receiving the PDE4 inhibitor + immune checkpoint inhibitor group were intraperitoneally injected with, for example, 4 mg / kg of PDE4 inhibitor and, for example, 2 mg / kg of immune checkpoint inhibitor (e.g., PD-L1 antibody), for a total of 6 administrations. Simultaneously, the PDE4 inhibitor group and the immune checkpoint inhibitor group were injected separately with the same dose of PDE4 inhibitor and immune checkpoint inhibitor, respectively, in the same manner. The blank control group was injected with the same dose of physiological saline. Day 1 was defined as the day of the first injection. Afterwards, the mice's body weight and tumor size were recorded: tumor volume (mm). 3 = Length (L) × Width (W)2 / 2, and Luciferin fluorescence imaging was performed on the tumors, i.e., 100 μL of 1 mg / mL D-fluorescein potassium aqueous solution was prepared and injected intraperitoneally into each mouse. 10 min after injection, Luciferin fluorescence imaging was performed on the tumors using a small animal in vivo imaging system (model: IVIS Lumina XRMS Series III).

[0826] The results show that the combination of the PDE4 selective inhibitor and the immune checkpoint inhibitor in this application can inhibit tumor growth, and the two have a synergistic effect and / or good safety.

[0827] 2.3 Roflumilast and anti-PD-L1 antibody synergistically inhibit melanoma growth

[0828] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were selected, and melanoma cells were cultured in vitro to the logarithmic growth phase. The cells were collected and resuspended in PBS buffer. The collected cells were injected subcutaneously into the legs of the mice, with each mouse receiving 5 × 10⁵ cells. 5 Cells were used to establish a subcutaneous tumor model.

[0829] (2) After tumor formation, mice were divided into four experimental groups: a blank control group, a PDE4 inhibitor group, an immune checkpoint inhibitor group, and a PDE4 inhibitor + immune checkpoint inhibitor group. Every 3 days, mice receiving the PDE4 inhibitor + immune checkpoint inhibitor group were intraperitoneally injected with, for example, 4 mg / kg of PDE4 inhibitor and, for example, 2 mg / kg of immune checkpoint inhibitor (e.g., PD-L1 antibody), for a total of 6 administrations. Simultaneously, the PDE4 inhibitor group and the immune checkpoint inhibitor group were injected separately with the same dose of PDE4 inhibitor and immune checkpoint inhibitor, respectively, in the same manner. The blank control group was injected with the same dose of physiological saline. Day 1 was defined as the day of the first injection. Afterwards, the mice's body weight and tumor size were recorded: tumor volume (mm). 3 = Length (L) × Width (W) 2 / 2, and Luciferin fluorescence imaging was performed on the tumors, i.e., 100 μL of 1 mg / mL D-fluorescein potassium aqueous solution was prepared and injected intraperitoneally into each mouse. 10 min after injection, Luciferin fluorescence imaging was performed on the tumors using a small animal in vivo imaging system (model: IVIS Lumina XRMS Series III).

[0830] The results show that the combination of the PDE4 selective inhibitor and the immune checkpoint inhibitor in this application can inhibit tumor growth, and the two have a synergistic effect and / or good safety.

[0831] 2.4 Roflumilast and anti-PD-L1 antibody synergistically inhibit lymphoma growth

[0832] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were selected. Lymphoma cells were cultured in vitro to the logarithmic growth phase, and the cells were collected and resuspended in PBS buffer. The collected cells were injected subcutaneously into the legs of the mice, with each mouse receiving 5 × 10⁶ cells. 5 Cells were used to establish a subcutaneous tumor model.

[0833] (2) After tumor formation, mice were divided into four experimental groups: a blank control group, a PDE4 inhibitor group, an immune checkpoint inhibitor group, and a PDE4 inhibitor + immune checkpoint inhibitor group. Every 3 days, mice receiving the PDE4 inhibitor + immune checkpoint inhibitor group were intraperitoneally injected with, for example, 4 mg / kg of PDE4 inhibitor and, for example, 2 mg / kg of immune checkpoint inhibitor (e.g., PD-L1 antibody), for a total of 6 administrations. Simultaneously, the PDE4 inhibitor group and the immune checkpoint inhibitor group were injected separately with the same dose of PDE4 inhibitor and immune checkpoint inhibitor, respectively, in the same manner. The blank control group was injected with the same dose of physiological saline. Day 1 was defined as the day of the first injection. Afterwards, the mice's body weight and tumor size were recorded: tumor volume (mm). 3 = Length (L) × Width (W) 2 / 2, and Luciferin fluorescence imaging was performed on the tumors, i.e., 100 μL of 1 mg / mL D-fluorescein potassium aqueous solution was prepared and injected intraperitoneally into each mouse. 10 min after injection, Luciferin fluorescence imaging was performed on the tumors using a small animal in vivo imaging system (model: IVIS Lumina XRMS Series III).

[0834] The results show that the combination of the PDE4 selective inhibitor and the immune checkpoint inhibitor in this application can inhibit tumor growth, and the two have a synergistic effect and / or good safety.

[0835] 2.5 Roflumilast and anti-PD-L1 antibody synergistically inhibit the growth of hematologic malignancies

[0836] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were selected. Blood tumor cells were cultured in vitro to the logarithmic growth phase, and the cells were collected and resuspended in PBS buffer. The collected cells were injected subcutaneously into the leg of each mouse, with each mouse receiving 5 × 10⁶ cells. 5 Cells were used to establish a subcutaneous tumor model.

[0837] (2) After tumor formation, mice were divided into four experimental groups: a blank control group, a PDE4 inhibitor group, an immune checkpoint inhibitor group, and a PDE4 inhibitor + immune checkpoint inhibitor group. Every 3 days, mice receiving the PDE4 inhibitor + immune checkpoint inhibitor group were intraperitoneally injected with, for example, 4 mg / kg of PDE4 inhibitor and, for example, 2 mg / kg of immune checkpoint inhibitor (e.g., PD-L1 antibody), for a total of 6 administrations. Simultaneously, the PDE4 inhibitor group and the immune checkpoint inhibitor group were injected separately with the same dose of PDE4 inhibitor and immune checkpoint inhibitor, respectively, in the same manner. The blank control group was injected with the same dose of physiological saline. Day 1 was defined as the day of the first injection. Afterwards, the mice's body weight and tumor size were recorded: tumor volume (mm). 3 = Length (L) × Width (W) 2 / 2, and Luciferin fluorescence imaging was performed on the tumors, i.e., 100 μL of 1 mg / mL D-fluorescein potassium aqueous solution was prepared and injected intraperitoneally into each mouse. 10 min after injection, Luciferin fluorescence imaging was performed on the tumors using a small animal in vivo imaging system (model: IVIS Lumina XRMS Series III).

[0838] The results show that the combination of the PDE4 selective inhibitor and the immune checkpoint inhibitor in this application can inhibit tumor growth, and the two have a synergistic effect and / or good safety.

[0839] 2.6 Roflumilast and anti-PD-1 antibody synergistically inhibit colon cancer growth

[0840] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were used to culture colon cancer cells, such as MC38 cells, in vitro. After reaching the logarithmic growth phase, the cells were collected and resuspended in PBS buffer. The collected cells were injected subcutaneously into the legs of the mice, with each mouse receiving 5 × 10⁶ cells. 5 Cells were used to establish a subcutaneous tumor model.

[0841] (2) After tumor formation, mice were divided into four experimental groups: a blank control group, a PDE4 inhibitor group, an immune checkpoint inhibitor group, and a PDE4 inhibitor + immune checkpoint inhibitor group. Every 3 days, mice receiving the PDE4 inhibitor + immune checkpoint inhibitor group were intraperitoneally injected with, for example, 4 mg / kg of PDE4 inhibitor and, for example, 2 mg / kg of immune checkpoint inhibitor (e.g., PD-1 antibody, such as Nivolumab, Pembrolizumab, Toripalimab, Sintilimab, Camrelizumab, etc.), for a total of 6 times. Simultaneously, the PDE4 inhibitor group and the immune checkpoint inhibitor group were injected separately with the same dose of PDE4 inhibitor and immune checkpoint inhibitor, respectively, in the same manner. The blank control group was injected with the same dose of saline. Day 1 was the day of the first injection. Afterwards, the mouse's body weight and tumor size were recorded: tumor volume (mm). 3 = Length (L) × Width (W) 2 / 2, and Luciferin fluorescence imaging was performed on the tumors, i.e., 100 μL of 1 mg / mL D-fluorescein potassium aqueous solution was prepared and injected intraperitoneally into each mouse. 10 min after injection, Luciferin fluorescence imaging was performed on the tumors using a small animal in vivo imaging system (model: IVIS Lumina XRMS Series III).

[0842] The results show that the combination of the PDE4 selective inhibitor and the immune checkpoint inhibitor in this application can inhibit tumor growth, and the two have a synergistic effect and / or good safety.

[0843] 2.7 Roflumilast and anti-PD-1 antibody synergistically inhibit breast cancer growth

[0844] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were used to culture breast cancer cells in vitro to the logarithmic growth phase. The cells were collected and resuspended in PBS buffer. The collected cells were injected subcutaneously into the legs of the mice, with each mouse receiving 5 × 10⁶ cells. 5 Cells were used to establish a subcutaneous tumor model.

[0845] (2) After tumor formation, mice were divided into four experimental groups: a blank control group, a PDE4 inhibitor group, an immune checkpoint inhibitor group, and a PDE4 inhibitor + immune checkpoint inhibitor group. Every 3 days, mice in the PDE4 inhibitor + immune checkpoint inhibitor group were intraperitoneally injected with, for example, 4 mg / kg of PDE4 inhibitor and, for example, 2 mg / kg of immune checkpoint inhibitor (e.g., PD-1 antibody), for a total of 6 administrations. Simultaneously, the PDE4 inhibitor group and the immune checkpoint inhibitor group were injected separately with the same dose of PDE4 inhibitor and immune checkpoint inhibitor, respectively, in the same manner. The blank control group was injected with the same volume of saline. Day 1 was the day of the first injection. Afterwards, the mouse's body weight and tumor size were recorded: tumor volume (mm). 3 = Length (L) × Width (W) 2 / 2, and Luciferin fluorescence imaging was performed on the tumors, i.e., 100 μL of 1 mg / mL D-fluorescein potassium aqueous solution was prepared and injected intraperitoneally into each mouse. 10 min after injection, Luciferin fluorescence imaging was performed on the tumors using a small animal in vivo imaging system (model: IVIS Lumina XRMS Series III).

[0846] The results show that the combination of the PDE4 selective inhibitor and the immune checkpoint inhibitor in this application can inhibit tumor growth, and the two have a synergistic effect and / or good safety.

[0847] 2.8 Roflumilast and anti-PD-1 antibody synergistically inhibit melanoma growth

[0848] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were selected, and melanoma cells were cultured in vitro to the logarithmic growth phase. The cells were collected and resuspended in PBS buffer. The collected cells were injected subcutaneously into the legs of the mice, with each mouse receiving 5 × 10⁵ cells. 5 Cells were used to establish a subcutaneous tumor model.

[0849] (2) After tumor formation, mice were divided into four experimental groups: a blank control group, a PDE4 inhibitor group, an immune checkpoint inhibitor group, and a PDE4 inhibitor + immune checkpoint inhibitor group. Every 3 days, mice in the PDE4 inhibitor + immune checkpoint inhibitor group were intraperitoneally injected with, for example, 4 mg / kg of PDE4 inhibitor and, for example, 2 mg / kg of immune checkpoint inhibitor (e.g., PD-1 antibody), for a total of 6 administrations. Simultaneously, the PDE4 inhibitor group and the immune checkpoint inhibitor group were injected separately with the same dose of PDE4 inhibitor and immune checkpoint inhibitor, respectively, in the same manner. The blank control group was injected with the same volume of saline. Day 1 was the day of the first injection. Afterwards, the mouse's body weight and tumor size were recorded: tumor volume (mm). 3 = Length (L) × Width (W) 2 / 2, and Luciferin fluorescence imaging was performed on the tumors, i.e., 100 μL of 1 mg / mL D-fluorescein potassium aqueous solution was prepared and injected intraperitoneally into each mouse. 10 min after injection, Luciferin fluorescence imaging was performed on the tumors using a small animal in vivo imaging system (model: IVIS Lumina XRMS Series III).

[0850] The results show that the combination of the PDE4 selective inhibitor and the immune checkpoint inhibitor in this application can inhibit tumor growth, and the two have a synergistic effect and / or good safety.

[0851] 2.9 Roflumilast and anti-CTLA-4 antibody synergistically inhibit colon cancer growth

[0852] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were used to culture colon cancer cells, such as MC38 cells, in vitro. After reaching the logarithmic growth phase, the cells were collected and resuspended in PBS buffer. The collected cells were injected subcutaneously into the legs of the mice, with each mouse receiving 5 × 10⁶ cells. 5 Cells were used to establish a subcutaneous tumor model.

[0853] (2) After tumor formation, mice were divided into four experimental groups: a blank control group, a PDE4 inhibitor group, an immune checkpoint inhibitor group, and a PDE4 inhibitor + immune checkpoint inhibitor group. Every 3 days, mice receiving the PDE4 inhibitor + immune checkpoint inhibitor group were intraperitoneally injected with, for example, 4 mg / kg of PDE4 inhibitor and, for example, 2 mg / kg of immune checkpoint inhibitor (e.g., CTLA-4 antibody), for a total of 6 administrations. Simultaneously, the PDE4 inhibitor group and the immune checkpoint inhibitor group were injected separately with the same dose of PDE4 inhibitor and immune checkpoint inhibitor, respectively, in the same manner. The blank control group was injected with the same dose of physiological saline. Day 1 was defined as the day of the first injection. Afterwards, the mice's body weight and tumor size were recorded: tumor volume (mm). 3 = Length (L) × Width (W) 2 / 2, and Luciferin fluorescence imaging was performed on the tumors, i.e., 100 μL of 1 mg / mL D-fluorescein potassium aqueous solution was prepared and injected intraperitoneally into each mouse. 10 min after injection, Luciferin fluorescence imaging was performed on the tumors using a small animal in vivo imaging system (model: IVIS Lumina XRMS Series III).

[0854] The results show that the combination of the PDE4 selective inhibitor and the immune checkpoint inhibitor in this application can inhibit tumor growth, and the two have a synergistic effect and / or good safety.

[0855] 2.10 Roflumilast and anti-LAG-3 antibody synergistically inhibit colon cancer growth

[0856] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were used to culture colon cancer cells, such as MC38 cells, in vitro. After reaching the logarithmic growth phase, the cells were collected and resuspended in PBS buffer. The collected cells were injected subcutaneously into the legs of the mice, with each mouse receiving 5 × 10⁶ cells. 5 Cells were used to establish a subcutaneous tumor model.

[0857] (2) After tumor formation, mice were divided into four experimental groups: a blank control group, a PDE4 inhibitor group, an immune checkpoint inhibitor group, and a PDE4 inhibitor + immune checkpoint inhibitor group. Every 3 days, mice receiving the PDE4 inhibitor + immune checkpoint inhibitor group were intraperitoneally injected with, for example, 4 mg / kg of PDE4 inhibitor and, for example, 2 mg / kg of immune checkpoint inhibitor (e.g., LAG-3 antibody), for a total of 6 administrations. Simultaneously, the PDE4 inhibitor group and the immune checkpoint inhibitor group were injected separately with the same dose of PDE4 inhibitor and immune checkpoint inhibitor, respectively, in the same manner. The blank control group was injected with the same dose of physiological saline. Day 1 was the day of the first injection. Afterwards, the mouse's body weight and tumor size were recorded: tumor volume (mm). 3 = Length (L) × Width (W) 2 / 2, and Luciferin fluorescence imaging was performed on the tumors, i.e., 100 μL of 1 mg / mL D-fluorescein potassium aqueous solution was prepared and injected intraperitoneally into each mouse. 10 min after injection, Luciferin fluorescence imaging was performed on the tumors using a small animal in vivo imaging system (model: IVIS Lumina XRMS Series III).

[0858] The results show that the combination of the PDE4 selective inhibitor and the immune checkpoint inhibitor in this application can inhibit tumor growth, and the two have a synergistic effect and / or good safety.

[0859] 2.11 Roflumilast derivatives and anti-PD-L1 antibodies synergistically inhibit colon cancer growth

[0860] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were used to culture colon cancer cells, such as MC38 cells, in vitro. After reaching the logarithmic growth phase, the cells were collected and resuspended in PBS buffer. The collected cells were injected subcutaneously into the legs of the mice, with each mouse receiving 5 × 10⁶ cells. 5 Cells were used to establish a subcutaneous tumor model.

[0861] (2) After tumor formation, mice were divided into four experimental groups: a blank control group, a PDE4 inhibitor group, an immune checkpoint inhibitor group, and a PDE4 inhibitor + immune checkpoint inhibitor group. Every 3 days, mice receiving the PDE4 inhibitor + immune checkpoint inhibitor group were intraperitoneally injected with, for example, 4 mg / kg of a PDE4 inhibitor (e.g., a Roflumilast derivative) and, for example, 2 mg / kg of an immune checkpoint inhibitor (e.g., a PD-L1 antibody), for a total of 6 administrations. Simultaneously, the PDE4 inhibitor group and the immune checkpoint inhibitor group were injected separately with the same dose of PDE4 inhibitor and immune checkpoint inhibitor, respectively, in the same manner. The blank control group was injected with the same dose of saline. Day 1 was the day of the first injection. Afterwards, mouse weight and tumor size were measured and recorded: tumor volume (mm). 3 = Length (L) × Width (W) 2 / 2, and Luciferin fluorescence imaging was performed on the tumors, i.e., 100 μL of 1 mg / mL D-fluorescein potassium aqueous solution was prepared and injected intraperitoneally into each mouse. 10 min after injection, Luciferin fluorescence imaging was performed on the tumors using a small animal in vivo imaging system (model: IVIS LuminaXRMS Series III).

[0862] The results show that the combination of the PDE4 selective inhibitor and the immune checkpoint inhibitor in this application can inhibit tumor growth, and the two have a synergistic effect and / or good safety.

[0863] 2.12 Other selective PDE4 inhibitors synergistically inhibit colon cancer growth with anti-PD-L1 antibodies.

[0864] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were used to culture colon cancer cells, such as MC38 cells, in vitro. After reaching the logarithmic growth phase, the cells were collected and resuspended in PBS buffer. The collected cells were injected subcutaneously into the legs of the mice, with each mouse receiving 5 × 10⁶ cells. 5 Cells were used to establish a subcutaneous tumor model.

[0865] (2) After tumor formation, the mice were divided into four experimental groups: blank control, PDE4 inhibitor group, immune checkpoint inhibitor group, and PDE4 inhibitor + immune checkpoint inhibitor group. Mice receiving a combination of PDE4 inhibitors and immune checkpoint inhibitors were intraperitoneally injected every 3 days with, for example, 4 mg / kg of a selective PDE4 inhibitor (e.g., Apremilast, Cresaborole, Drotaverine, CC-1088, BPN14770, GSK356278, HT-0712, TAK-648, Zembrin, ASP9831, Etazolate, Piclamilast, Rolipram, Cilomilast, GSK256066, AWD 12–281, Quinolyl oxazole, DC-TA-46, Filaminast, and / or Glaucine) and, for example, 2 mg / kg of an immune checkpoint inhibitor (e.g., PD-L1 antibody). This was repeated 6 times. Simultaneously, the PDE4 inhibitor group and the immune checkpoint inhibitor group were injected separately with the same dose of PDE4 inhibitor and immune checkpoint inhibitor, respectively, in the same manner. The blank control group was injected with the same dose of physiological saline. Day 1 was designated as the day of the first injection. Afterwards, mouse weight and tumor size were recorded: tumor volume (mm). 3 = Length (L) × Width (W) 2 / 2, and Luciferin fluorescence imaging was performed on the tumors, i.e., 100 μL of 1 mg / mL D-fluorescein potassium aqueous solution was prepared and injected intraperitoneally into each mouse. 10 min after injection, Luciferin fluorescence imaging was performed on the tumors using a small animal in vivo imaging system (model: IVIS Lumina XRMS Series III).

[0866] The results show that the combination of the PDE4 selective inhibitor and the immune checkpoint inhibitor in this application can inhibit tumor growth, and the two have a synergistic effect and / or good safety.

[0867] Example 3: Other selective inhibitors besides PDE4, when used in combination with immune checkpoint inhibitors, did not show significant synergistic tumor-suppressing effects.

[0868] (1) Tumor formation in mice. Six- to eight-week-old female C57 mice were selected. Tumor cells, such as colon cancer cells (e.g., MC38 cells), were cultured in vitro until the logarithmic growth phase. The cells were then collected and resuspended in PBS buffer. The collected cells were injected subcutaneously into the legs of the mice, with each mouse receiving 5 × 10⁶ cells. 5 Cells were used to establish a subcutaneous tumor model.

[0869] (2) After tumor formation, mice were divided into four experimental groups: a blank control group, a group receiving other PDE inhibitors (e.g., selective PDE5 inhibitors such as Tadalafil, Sildenafil citrate, Kuraridine, etc.), an immune checkpoint inhibitor group, and a group receiving other PDE inhibitors plus an immune checkpoint inhibitor. Every 3 days, mice receiving other PDE inhibitors plus an immune checkpoint inhibitor were intraperitoneally injected with, for example, 4 mg / kg of another selective PDE inhibitor and, for example, 2 mg / kg of an immune checkpoint inhibitor (e.g., PD-L1 antibody), for a total of 6 administrations. Simultaneously, the other PDE inhibitor group and the immune checkpoint inhibitor group were injected separately with the same dose of other PDE inhibitor and immune checkpoint inhibitor, respectively, in the same manner. The blank control group was injected with the same dose of physiological saline. Day 1 was the day of the first injection. Afterwards, the mouse's body weight and tumor size were recorded: tumor volume (mm). 3 = Length (L) × Width (W) 2 / 2, and Luciferin fluorescence imaging was performed on the tumors, i.e., 100 μL of a 1 mg / mL D-fluorescein potassium aqueous solution was prepared and injected intraperitoneally into each mouse. 10 min after injection, Luciferin fluorescence imaging was performed on the tumors using a small animal in vivo imaging system (model: IVIS Lumina XRMS SeriesIII).

[0870] The results showed that, apart from PDE4, other selective inhibitors, such as selective PDE5 inhibitors, did not have a significant synergistic antitumor effect when used in combination with immune checkpoint inhibitors.

[0871] Example 4: PDE4 inhibitors inhibit metastasis

[0872] Different concentrations of PDE4 inhibitors, such as 5 μM, 10 μM, or 20 μM, were administered to verify their inhibitory effect on metastasis in a scratch assay on MC38. PDE4 inhibitors such as roflumilast and BPN14770 were used. GSK256066 Rolipram ), or dipyridamole, ).

[0873] like Figure 3 As shown, roflumilast inhibits metastasis. Figure 4 The results of BPN14770 inhibiting metastasis are shown. Figure 5 As shown, the results of GSK256066 inhibiting metastasis. Figure 6 As shown, the results of cyclophosphamide inhibiting metastasis. Figure 7The results show that dipyridamole inhibits metastasis. The results demonstrate that PDE4 inhibitors have a significant metastasis-inhibiting effect.

[0874] Example 5: PDE4 inhibitors inhibit tumor metastasis

[0875] In a mouse model of breast cancer lung metastasis (using 4T1 breast tumor cells), roflumilast was administered to investigate the effect of PDE4 inhibitors on inhibiting tumor metastasis. Figure 8 As shown, roflumilast inhibits tumor metastasis. The results indicate that PDE4 inhibitors have a significant effect in inhibiting tumor metastasis.

[0876] Example 6: Combination of PDE4 inhibitors and immune checkpoint inhibitors to suppress tumors.

[0877] In a mouse tumor model, the efficacy of PDE4 inhibitors combined with immune checkpoint inhibitors in inhibiting tumors was tested by administering roflumilast (Rof group), PD-1 antibody (InVivoMab, PD-1 group), or a combination of roflumilast and PD-1 antibody (Rof+PD-1 group).

[0878] like Figure 9 The results show the tumor-suppressive effect of combining PDE4 inhibitors with immune checkpoint inhibitors. The results indicate that the combination of PDE4 inhibitors and immune checkpoint inhibitors has a significant synergistic effect in inhibiting tumor growth.

[0879] Example 7: PDE4 knockout inhibits metastasis

[0880] In a mouse model of colon cancer liver metastasis (using MC38 colon tumor cells), PDE4 was knocked out, for example, by designing sgRNAs based on two regions of chr13:108790711-110092503. Figure 10 The results show that PDE4 knockout significantly inhibits tumor metastasis.

[0881] The foregoing detailed description is provided by way of explanation and example and is not intended to limit the scope of the appended claims. Various variations of the embodiments listed herein will be apparent to those skilled in the art and are reserved within the scope of the appended claims and their equivalents.

Claims

1. The use of PDE4 selective inhibitors in the preparation of drugs to inhibit tumor metastasis, among which, The selective PDE4 inhibitor is roflumilast, which is used to inhibit the metastasis of colon cancer or breast cancer.

2. The use of PDE4 selective inhibitors in the preparation of drugs to inhibit tumor metastasis, among which, The selective PDE4 inhibitor is BPN14770, and the drug is used to inhibit colorectal cancer metastasis.

3. The use of PDE4 selective inhibitors in the preparation of drugs to inhibit tumor metastasis, among which, The selective PDE4 inhibitor is GSK256066, and the drug is used to inhibit colorectal cancer metastasis.

4. The use of PDE4 selective inhibitors in the preparation of drugs to inhibit tumor metastasis, among which, The selective PDE4 inhibitor is dipyridamole, and the drug is used to inhibit colorectal cancer metastasis.

5. The use according to any one of claims 1-4, wherein the medicament further comprises an immune checkpoint inhibitor.

6. The use according to claim 5, wherein the immune checkpoint inhibitor is an anti-PD-L1 antibody or its antigen-binding fragment, or an anti-PD-1 antibody or its antigen-binding fragment.

7. The use according to claim 5, wherein the immune checkpoint inhibitor is selected from the group consisting of nivolumab, pembrolizumab, BMS-936559, MPDL3280A, MEDI4736, AMP-224 and MSB0010718C.

8. The use according to claim 6, wherein the antibody is selected from: chimeric antibodies, humanized antibodies, and fully human antibodies.

9. The use according to claim 6, wherein the antigen-binding fragment is selected from: Fab, Fv, scFv, Fab' and (Fab')2.

10. The use according to claim 5, wherein the mass ratio of the effective amount of the PDE4 selective inhibitor to the effective amount of the immune checkpoint inhibitor is from 9:1 to 1:4.

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