Pharmaceutical composition for inhibiting tuberculosis bacillus

Abstract

The present invention relates to a pharmaceutical composition for inhibiting tuberculosis bacilli, the pharmaceutical composition comprising contezolid, bedaquiline, pretomanid and a pharmaceutically acceptable carrier. The present invention discloses for the first time that contezolid (MRX-I) has excellent activity in inhibiting tuberculosis bacilli, and the combination of contezolid with bedaquiline and pretomanid shows excellent antibacterial activity.

Description

Technical Field

[0001] The invention provides a pharmaceutical composition for inhibiting tuberculosis bacillus, belonging to the field of medicine. Background Art

[0002] Tuberculosis is a chronic infectious disease caused by Mycobacterium tuberculosis and is one of the major public health issues of global concern. The disease was declared a global epidemic by the World Health Organization (WHO) in 1990 and has affected more than one-third of the world's population. In particular, the emergence of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) since the 1980s has made the situation of tuberculosis prevention and control increasingly severe. Multidrug-resistant tuberculosis refers to tuberculosis bacteria that are resistant to any two or more of the drugs among streptomycin, isoniazid, rifampicin, ethambutol, and pyrazinamide. Extensively drug-resistant tuberculosis refers to tuberculosis bacteria that are resistant to any fluoroquinolone drugs and at least one of the three second-line injectable drugs (capreomycin sulfate, kanamycin and amikacin) in addition to multidrug-resistant tuberculosis.

[0003] In response to the urgent situation of the rapid spread of drug-resistant tuberculosis, the World Health Organization has proposed a multi-level combined drug regimen based on the current clinical first-line and second-line anti-tuberculosis drugs. Through the combined treatment of multiple mechanism drugs, cross-drug resistance can be avoided and the incidence of drug-resistant bacteria can be reduced. However, in the long run, there are still two difficulties in the prevention and treatment of tuberculosis. First, there is a lack of drugs that can cure quickly. The existing medication regimen requires more than 6 months of uninterrupted treatment, with high treatment costs and difficulty in management. Once patients are out of treatment, they are very likely to develop drug-resistant tuberculosis. Secondly, the problem of drug resistance is becoming more and more serious, especially for multidrug-resistant and extensively drug-resistant tuberculosis. There is currently a lack of effective treatment methods, which poses a serious threat to the control of tuberculosis. Therefore, the development of a new generation of drugs that can treat drug-resistant tuberculosis infection and can take effect quickly has become a top priority for the prevention and treatment of modern tuberculosis.

[0004] Linezolid is the first oxazolidinone antibiotic approved for marketing. It has played a great role in the treatment of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) infections. However, the safety and tolerability of long-term use of linezolid are still worthy of attention, which limits the upper limit of linezolid use and makes it difficult to quickly and effectively treat drug-resistant tuberculosis infections. In addition, previous clinical studies have found that the proportion of discontinuation of linezolid due to severe adverse reactions is 15.81%.

[0005]

[0006] Bedaquiline (TMC207), produced by Johnson & Johnson Pharmaceuticals, was approved by the U.S. FDA on December 28, 2012. It is the first new anti-tuberculosis drug with a new mechanism of action since rifampicin (RFP) in 1974. It is also the world's first new drug approved by the FDA for the treatment of multidrug-resistant tuberculosis since the 1970s. Bedaquiline can cause the side effect of QT prolongation.

[0007]

[0008] In August 2019, the U.S. FDA announced that it had approved the marketing of Pretomanid, developed by the non-profit organization TB Alliance, for use in combination with bedaquiline and linezolid to treat certain highly drug-resistant tuberculosis (TB) patients. This is the third new anti-tuberculosis drug approved by the FDA in nearly 40 years, and the first new tuberculosis drug developed and marketed by a non-profit organization.

[0009]

[0010] The applicant's previous Chinese patent application CN101720325A discloses an oxazolidinone antibacterial compound, which discloses the compound contezolid (MRX-I), which shows high antibacterial activity in both in vivo and in vitro antibacterial models, but there are currently no reports on its use in combined anti-tuberculosis therapy research.

[0011] Summary of the invention

[0012] In view of the above problems, the present invention aims to provide a safe, highly tolerable, fast-acting compound and pharmaceutical composition for treating drug-resistant tuberculosis infection.

[0013] The present invention provides a pharmaceutical composition for inhibiting tuberculosis bacteria, comprising:

[0014] A compound of formula I or a pharmaceutically acceptable salt thereof, a compound of formula II, a compound of formula III, and a pharmaceutically acceptable carrier;

[0015]

[0016] The compound of formula I (contezolid, MRX-I) in the three-drug combination provided by the present invention has comparable anti-tuberculosis activity to linezolid, and its toxicity is significantly lower than that of linezolid in long-term toxicity evaluation experiments in rats and dogs, and has better clinical safety, tolerability and compliance than linezolid. The three-drug combination provided by the present invention has a better inhibitory effect on Mycobacterium tuberculosis than the combination of bedaquiline / Pretomanid.

[0017] Preferably, the mass ratio of the sum of the compound of formula II and the compound of formula III to the mass ratio of the compound of formula I or its pharmaceutically acceptable salt is (0.3-2.4):1.

[0018] More preferably, the mass ratio of the sum of the mass of the compound of formula II and the compound of formula III to the mass ratio of the compound of formula I or its pharmaceutically acceptable salt is (0.5-1.0):1.

[0019] In a preferred example, the mass ratio of the compound of formula II and the compound of formula III to the compound of formula I or its pharmaceutically acceptable salt is 5:8.

[0020] Preferably, the mass ratio of the compound of formula II to the compound of formula III is 1:(0.5-8).

[0021] In a preferred example, the mass ratio of the compound of formula II to the compound of formula III is 1:4.

[0022] The present invention provides for the first time a combination of contezolid (MRX-I) with bedaquiline and pretomanid. The combination is superior to the existing bedaquiline / pretomanid combination and is expected to become a new generation of fast-acting drugs that can treat multidrug-resistant tuberculosis and extensively drug-resistant tuberculosis infections. DETAILED DESCRIPTION

[0023] The present invention is further described below in conjunction with the following embodiments. It should be understood that the following embodiments are only used to illustrate the present invention, rather than to limit the present invention.

[0024] First, the present invention provides a compound of formula I or a pharmaceutically acceptable salt thereof for use in preparing a drug for inhibiting tuberculosis.

[0025]

[0026] The preparation of the compound of formula I (contezolid, MRX-I) can be found in the applicant's previous Chinese patent application CN101720325A.

[0027] Pharmaceutically acceptable salts of the compound of formula I include, but are not limited to, (1) acid addition salts formed by the compound of formula I and an inorganic acid or an organic acid; (2) salts formed by the acidic protons in the compound of formula I being replaced by metal ions or coordinated with organic bases. The inorganic acids include hydrochloric acid, hydrobromic acid, phosphoric acid, etc.; the organic acids include acetic acid, lactic acid, tartaric acid, citric acid, salicylic acid, etc.; the metal ions include sodium ions, potassium ions, calcium ions, etc.; the organic bases include ethanolamine, N-methylglucamine, etc.

[0028] In vitro anti-tuberculosis activity test of the compound of formula I

[0029] The MIC (minimum inhibitory concentration) was determined using a microplate to test the inhibitory activity of the compound of formula I against clinically isolated drug-resistant strains FQ-R1, INH-R1, INH-R2, RIF-R1, and RIF-R2 (strains provided by IDRI) (using existing anti-tuberculosis drugs rifampicin, isoniazid, levofloxacin, and linezolid as controls). Experimental method: The compound was dissolved in DMSO and diluted 2-fold in 20 different concentrations into a 96-well plate containing 7H9-Tw-OADC culture medium, with a final DMSO solubility of 2%. The highest drug concentration was 200uM. Each plate contained a solvent control and a 100uM rifampicin control. Various tuberculosis bacteria were added to the 96-well plate and cultured for 5 days. The bacterial growth was measured by OD 590 Detection. The MIC value (minimum concentration at which growth is completely inhibited) was obtained by calculating the dose response curve (using GraphPad Prism6 to simulate the Gompertz model). The results are shown in Table 1 below.

[0030] Table 1:

[0031]

[0032] As can be seen from Table 1, the compound of formula I of the present invention has comparable anti-tuberculosis activity to linezolid, and has no cross-resistance with rifampicin, isoniazid, and levofloxacin, that is, it shows good antibacterial activity against the respective drug-resistant strains of rifampicin, isoniazid, and levofloxacin, and can not only treat tuberculosis infection, but also has the advantage of reducing the generation of drug-resistant bacteria, and also has the potential for clinical combined administration.

[0033] The compound of formula I was subjected to a 13-week continuous administration toxicity evaluation test on SD rats. After oral administration at different doses, the physiological and laboratory test indicators of the rats were observed to confirm the maximum dose (NOAEL) at which no adverse reactions were observed. Experimental method: The compound of formula I was dissolved in 0.5% sodium hydroxymethylcellulose solution and administered to animals by oral oral administration. The administration was twice a day (once in the morning and once in the afternoon, with an interval of about 10 hours between the two times) for 13 consecutive weeks. The administration volume was 10mL / kg / dose. The administration preparation was removed from the refrigerator at least 15 minutes before administration and placed at room temperature, and stirred continuously until the end of administration. The animals were observed twice a day (morning and afternoon), and the main observation indicators were death, abnormal performance, pain or discomfort. The toxicity test animals were observed once a day by the cage in the early stage of administration, the administration period and the recovery period, and the abnormal findings observed were recorded. Among them, during the administration period, cage observation was performed about 1 hour after the morning administration (based on the end time of the last animal / group administration), and the observation time in the recovery period was close to the administration period. Each toxicity test animal was observed clinically in detail before the grouping in the early stage of dosing; observed once before dosing on the first day of the dosing period, then once a week until the 13th week, observed once on the day of sacrifice at the end of the dosing period (limited to animals killed at the end), observed once on the first day of the recovery period, then once a week until the 4th week, and observed once the day before the end of the recovery period. Blood and urine samples were collected once on the 42nd day of the dosing period (all surviving animals), the 92nd day (limited to animals killed at the end of the recovery period), and the 29th day of the recovery period (limited to animals killed at the end of the recovery period). Hematological tests, coagulation tests, blood biochemical tests, urine routine tests, and bone marrow smears were performed. In this test, the NOAEL of the compound of formula I reached 100 mg / kg, and the literature reported that linezolid was only 10 mg / kg in the same test, indicating that the compound of formula I has better safety than linezolid and is more suitable for the requirements of long-term treatment of tuberculosis infection.

[0034] In a second aspect, the present invention provides a pharmaceutical composition for inhibiting Mycobacterium tuberculosis, comprising a compound of formula I or a pharmaceutically acceptable salt thereof, a compound of formula II (bedaquiline), a compound of formula III (pretomanid), and a pharmaceutically acceptable carrier;

[0035]

[0036] In the mouse combined infection model, bedaquiline / Pretomanid, bedaquiline / Pretomanid / linezolid, and bedaquiline / Pretomanid / compound of Formula I were compared by continuous administration of different doses for 4 weeks. The results are shown in Table 2.

[0037] Table 2

[0038]

[0039]

[0040] Experimental method: Female BALB / c mice were infected with approximately 4 log10 CFU of H37Rv tuberculosis bacteria by aerosol, and after 2 weeks of feeding, they began to receive oral drug treatment. The mice in the control group were killed on the first day after infection and before the start of drug treatment, and the lungs were dissected to determine the bacterial infection load after infection and before treatment. Bedaquiline was prepared every two weeks and dissolved in acidic HPCD solution, Pretomanid was prepared every month and dissolved in CM-2 solution, Linezolid was dissolved in 0.5% methylcellulose solution, and the compound of formula I was dissolved in 0.5% sodium hydroxymethylcellulose solution. As shown in Table 2, bedaquiline (B) 25 mg / kg, Pretomanid (Pa) 100 mg / kg, linezolid (L) 50 mg / kg and 100 mg / kg, and compound of formula I (Mrx) 50 mg / kg, 100 mg / kg and 200 mg / kg were administered in combination (L50 means 50 mg / kg of linezolid administered to the test mice; L100 means 100 mg / kg of linezolid administered to the test mice; Mrx50 means 50 mg / kg of MRX-I administered to the test mice; Mrx100 means 100 mg / kg of MRX-I administered to the test mice; Mrx200 means 200 mg / kg of MRX-I administered to the test mice; BPa means bedaquiline (25 mg / kg) / Pretomanid (100 mg / kg) administered to the test mice; BPaL50 means bedaquiline (2 5mg / kg) / Pretomanid (100mg / kg) / Linezolid (50mg / kg); BPaL100 refers to bedaquiline (25mg / kg) / Pretomanid (100mg / kg) / Linezolid (100mg / kg) administered to the test mice; BPaMrx50 refers to bedaquiline (25mg / kg) / Pretomanid (100mg / kg) / MRX-I (50mg / kg) administered to the test mice; BPaMrx100 refers to bedaquiline (25mg / kg) / Pretomanid (100mg / kg) / MRX-I (100mg / kg) administered to the test mice; BPaMrx200 refers to bedaquiline (25mg / kg) / Pretomanid (100mg / kg) / MRX-I (200mg / kg) administered to the test mice), gavage once a day for 5 consecutive days a week. After 6 weeks of continuous administration, the mice were dissected to determine the amount of bacterial infection in the lungs. As can be seen from Table 2, the drug combination administration regimen provided by the present invention (BPaMrx) is comparable to Bedaquiline / Pretomanid / Linezolid (BPaL) and superior to Bedaquiline / Pretomanid (BPa).Moreover, since the compound of formula I of the present invention has lower toxicity than linezolid and a higher tolerance, the dosage can be increased. For example, BPaMrx200 can eliminate the lung infection of the test mice after six weeks of administration, achieving a rapid therapeutic effect.

[0041] The above drug combination only shows the preferred ratio of each component, and the dosage ratio can be adjusted appropriately. For example, the total dosage of bedaquiline and pretomanid and the compound of formula I is preferably (0.3-2.4):1, more preferably (0.5-1):1, and a preferred example is 5:8. In addition, the dosage ratio of bedaquiline and pretomanid can be 1:(0.5-8), preferably 1:4).

[0042] The pharmaceutical composition can be a composition for injection, oral administration, inhalation or topical administration. For example, it can be formed into a form such as tablets, pills, capsules, suppositories, sterile injections or sterile powders together with carriers known in the art, such as excipients. It should be understood that the pharmaceutical composition can be administered simultaneously or separately for combined administration.

[0043] The above-described aspects are brief statements of the present invention, and those with ordinary skills in the art can make changes, equivalent substitutions and other types of changes to the invention proposed herein after reading the foregoing description. Therefore, the description should be regarded as exemplary.

Claims

1. A pharmaceutical composition for inhibiting Mycobacterium tuberculosis, characterized in that: The pharmaceutical composition comprises: A compound of formula I or a pharmaceutically acceptable salt thereof, a compound of formula II, a compound of formula III, and a pharmaceutically acceptable carrier; in, The mass ratio of the compound of formula II and the compound of formula III to the compound of formula I or a pharmaceutically acceptable salt thereof is 5:8; the mass ratio of the compound of formula II to the compound of formula III is 1:4.

Images