Monoclonal antibodies and their use in preparing drugs for treating cancer

Abstract

The present invention discloses a monoclonal antibody and its application in the preparation of a drug for treating cancer, and the monoclonal antibody EGFRvIII-22 specifically targeting EGFRvIII comprises a heavy chain variable region and a light chain variable region; the heavy chain variable region comprises HCDR1, HCDR2 and HCDR3 as shown in SEQ ID NO:1, SEQ ID NO:2 and SEQ ID NO:3, respectively; the light chain variable region comprises LCDR1, LCDR2 and LCDR3 as shown in SEQ ID NO:4, SEQ ID NO:5 and SEQ ID NO:6, respectively. The present invention has experimentally found that the treatment of EGFRvIII-22, a monoclonal antibody specifically targeting EGFRvIII, is superior to conventional chemotherapy in improving the total effective rate and survival period of cancer patients. At the same time, the positive improvement in quality of life and acceptable safety indicate that it has a wide range of application scenarios as a cancer treatment solution.

Description

Technical Field

[0001] The present invention relates to the field of biotechnology, and in particular to monoclonal antibodies and their application in preparing drugs for treating cancer. Background Art

[0002] Cancer is one of the most serious diseases that threaten human health. Globally, the incidence and mortality of cancer continue to rise, especially in developing countries. Among all types of cancer, lung cancer is the most deadly. The high incidence and mortality of lung cancer make it the leading cause of cancer-related death in the world. Lung cancer is divided into small cell lung cancer and non-small cell lung cancer, of which non-small cell lung cancer accounts for about 85% of all lung cancer cases. Although certain progress has been made in surgery, radiotherapy, chemotherapy and targeted therapy in recent years, the overall survival rate of lung cancer is still low, especially the prognosis of patients with advanced lung cancer is poor.

[0003] The epidermal growth factor receptor mutant EGFRvIII is a member of the epidermal growth factor receptor family. EGFRvIII is a common EGFR mutation that lacks exons 2-7, causing it to remain in an activated state. EGFRvIII is highly expressed in many tumors, especially lung cancer, while it is expressed at very low levels or not at all in normal tissues. This characteristic makes EGFRvIII an ideal tumor-specific marker and anti-tumor target.

[0004] A variety of tumor immunotherapies have been developed targeting the EGFRvIII target, but existing drugs or products still face some technical problems, such as insufficient targeting, off-target effects, strong rejection reactions, frequent tumor immune escape, and anti-tumor activity that needs to be enhanced. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and provide monoclonal antibodies and their use in the preparation of drugs for treating cancer. To achieve the above purpose, the present invention provides the following technical solutions:

[0006] In the first aspect, the present invention provides a monoclonal antibody EGFRvIII-22 specific for EGFRvIII, which comprises a heavy chain variable region and a light chain variable region; the heavy chain variable region comprises HCDR1, HCDR2 and HCDR3 as shown in SEQ ID NO:1, SEQ ID NO:2 and SEQID NO:3, respectively; the light chain variable region comprises LCDR1, LCDR2 and LCDR3 as shown in SEQ ID NO:4, SEQ ID NO:5 and SEQ ID NO:6, respectively.

[0007] In a second aspect, the present invention provides the above-mentioned monoclonal antibody specific for EGFRvIII

[0008] EGFRvIII-22, the amino acid sequence of the heavy chain variable region is shown in SEQ ID NO: 7, and the amino acid sequence of the light chain variable region is shown in SEQ ID NO: 8.

[0009] In a third aspect, the present invention also provides the use of the above-mentioned monoclonal antibody EGFRvIII-22 specifically targeting EGFRvIII in the preparation of a pharmaceutical composition for treating cancer, wherein the cancer is lung cancer.

[0010] Furthermore, the above-mentioned lung cancer is non-small cell lung cancer.

[0011] Furthermore, the above-mentioned pharmaceutical composition also contains a pharmaceutically acceptable carrier.

[0012] Furthermore, the above-mentioned pharmaceutical composition is in the form of an injection.

[0013] In a fourth aspect, the present invention also provides use of the above-mentioned monoclonal antibody EGFRvIII-22 specifically targeting EGFRvIII in combination with docetaxel in the preparation of a pharmaceutical composition for treating cancer.

[0014] Furthermore, the above-mentioned cancer is lung cancer.

[0015] Furthermore, the above-mentioned lung cancer is non-small cell lung cancer.

[0016] The difference between the present invention and the prior art is that the present invention achieves the following technical effects:

[0017] The present invention discovered through experiments that treatment with the monoclonal antibody EGFRvIII-22 specifically targeting EGFRvIII is superior to conventional chemotherapy in improving the total efficacy and survival of cancer patients. At the same time, the positive improvement in quality of life and acceptable safety indicate that it has a wide range of application scenarios as a cancer treatment option. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The effects of different treatment groups of the present invention on the cell survival rate of human lung cancer cells;

[0019] Figure 2 The effects of different treatment groups of the present invention on the expression of EGFRvIII protein in human lung cancer cells;

[0020] Figure 3 It is a comparison chart of the survival period between the treatment group of the present invention and the control group;

[0021] Figure 4 It is a comparison chart of changes in tumor marker levels between the treatment group of the present invention and the control group. DETAILED DESCRIPTION

[0022] The following examples are provided to facilitate a better understanding of the present invention, but are not intended to limit the present invention. The experimental methods in the following examples are conventional methods unless otherwise specified. The materials, reagents, etc. used in the following examples are commercially available unless otherwise specified.

[0023] Example 1 Preparation of human monoclonal antibody EGFRvIII-22

[0024] Recombinant human EGFRvIII protein (purity>95%, prepared by a standard expression system) was selected as the immunogen. Before each immunization, the recombinant protein was dissolved in physiological saline at a concentration of 2 mg / mL.

[0025] Five BALB / c mice were intraperitoneally injected with 100 μg of recombinant human EGFRvIII protein, mixed with Freund's complete adjuvant at a ratio of 1:1. After the initial immunization, booster immunization was performed again at the same dose at an interval of 2 weeks for a total of 4 times.

[0026] Three days after the last immunization, the mice were killed, the spleens were removed, and the spleen cells were mixed with SP2 / 0 mouse myeloma cells at a ratio of 3:1 under sterile conditions, and cell fusion was performed using 50% polyethylene glycol (PEG 1500); after fusion, the cells were immediately suspended in RPMI-1640 medium containing HAT medium, and the cells were distributed in 96-well plates for culture.

[0027] The first screening was performed on the 10th day after fusion, and the reactivity of antibodies in the culture supernatant to EGFRvIII was detected by ELISA. Positive clones with high specificity for human EGFRvIII protein and no reaction with normal mouse cells were screened. Multiple subclone screenings were performed on the positive clones in the initial screening until a monoclonal cell line that stably secreted anti-EGFRvIII antibodies was obtained. Finally, two hybridoma cell lines that stably secreted anti-EGFRvIII monoclonal antibodies were obtained, one of which was named EGFRvIII-22.

[0028] The hybridoma cell line EGFRvIII-22 was injected into the peritoneal cavity of BALB / c mice of the same type, 0.5 ml / mouse. Ten days after the injection, when the abdomen of the mouse was obviously swollen, the ascites was collected. The ascites was purified by Protein G affinity chromatography. The specific steps are as follows:

[0029] The column was balanced with equilibration buffer (20 mM Na2HPO4, 150 mM NaCl, pH 7.4); ascites was loaded and the column was washed with buffer to remove non-specific binding proteins; the antibody was eluted with elution buffer (0.1 M citric acid, pH 3.0); the elution peak was collected and immediately neutralized with 1 M Tris-HCl (pH 9.0); the antibody solution was concentrated and dialyzed into PBS buffer to adjust the antibody concentration to 1 mg / mL.

[0030] The titer of the purified antibody was determined by indirect ELISA. Human recombinant EGFRvIII protein (100 μg / mL), mouse EGFR protein (100 μg / mL), BSA protein (100 μg / mL) and E. coli lysate (100 μg / mL) were coated on ELISA plates to detect the specific reaction of the antibody. The results showed that the EGFRvIII-22 monoclonal antibody only specifically bound to the human EGFRvIII protein and did not react with other proteins.

[0031] Monoclonal antibody EGFRvIII-22 affinity determination:

[0032] Antigen coating: The recombinant human EGFRvIII protein was diluted in series starting from a starting concentration of 5 μg / mL; each diluted concentration of the protein solution was added to the ELISA plate for coating at 4°C overnight.

[0033] Antibody addition: dilute the monoclonal antibody EGFRvIII-22 in multiples, add it to the protein-coated ELISA wells, and incubate at 37°C for 1 hour.

[0034] Secondary antibody addition: Add HRP-labeled goat anti-mouse IgG and incubate at 37°C for 30 minutes.

[0035] Color development reaction: Add TMB color development solution and incubate at room temperature in the dark for 15 minutes; stop the reaction by adding stop solution (1M H2SO4).

[0036] Determine absorbance: Measure the absorbance (D(λ) value) of each well at a wavelength of 450 nm.

[0037] Data analysis: The reaction curve was drawn with the logarithm of the antibody concentration as the horizontal axis and the D(λ) value as the vertical axis. The D(λ) value of the flat section on each curve was taken as 100%, and the antibody concentration corresponding to the 50% D(λ) value was found on the curve. The affinity constant (Kaff) was calculated according to the following formula: Kaff = (n-1) / 2([Ab']t-[Ab]t), where [Ab']t and [Ab]t are the antibody concentrations corresponding to the 50% D(λ) value.

[0038] result

[0039] Affinity determination: The response curve of monoclonal antibody EGFRvIII-22 showed a typical dose-dependency. According to the response curve, the affinity constant of EGFRvIII-22 monoclonal antibody was calculated to be 1.35×10 -10 M, indicating that EGFRvIII-22 has a higher affinity.

[0040] Sequence identification: Through sequencing of the light and heavy chain variable regions, the heavy chain variable region sequence of the EGFRvIII-22 antibody was identified as shown in SEQ ID NO: 7, i.e., EVQLVESGGGLVQPGGSLRLSCAASGGYSGT YSSWVRQAPGKGLEWVAVISNGGSYNYADSVKGRFTISRDNAKIQNGGSYN YRLNSLQDRGTAVYYCAARHWYFDVWGQGTLVTVSS,

[0041] The light chain variable region sequence is shown in SEQ ID NO: 8, i.e., DIVLTQSPASLAVSLGQRATISCKSS QSQSLMNSGNQSYLAWYQQKPGQAPRLILQFESDNGVPDRFSGSGSGTDFTL KISRVEAEDVGVYYCQHYDSIPLTFGGGTKLEIK.

[0042] Example 2 In vitro anti-lung cancer cell experiment of EGFRvIII-22 monoclonal antibody and / or docetaxel

[0043] Human lung cancer H1975 cells (ATCC, catalog number: CRL-5908) were cultured in RPMI-1640 medium (containing 10% fetal bovine serum, 2 mM L-glutamine, 100 U / mL penicillin, 100 μg / mL streptomycin) at 37°C in a saturated humidity, 5% CO2 incubator after cell recovery, and subcultured after 0.25% trypsin digestion.

[0044] Cells in logarithmic growth phase were taken and digested with 0.25% trypsin to prepare single cell suspension, and the cell density was adjusted to 1×105 cells / mL, inoculated into 96-well plates, 100 μL per well, and cultured in a 5% CO2, saturated humidity, 37°C incubator for 24 hours. The groups were:

[0045] (1) Different concentrations (6.25, 12.5, 25, 50, 100 μg / mL) of EGFRvIII-22 mAb, i.e. mAb concentration group;

[0046] (2) different concentrations (6.25, 12.5, 25, 50, 100 μg / mL) of EGFRvIII-22 mAb combined with 100 nM docetaxel, i.e., combination group;

[0047] (3) PFT-μ was used as a positive control (100 μg / mL);

[0048] (4) docetaxel alone group (100 nM), i.e., docetaxel group;

[0049] (5) No drug was added as negative control. Three replicate wells were set up in each group. After 72 hours of continuous culture, 15 μL of MTT (5 g / L) was added to each well. Culture was continued for 4 hours. The culture medium was discarded and 150 μL of DMSO was added to each well. The cells were incubated in an incubator for 30 minutes. The cells were shaken on a micro-oscillator for 10 minutes to fully dissolve the crystals. The absorbance (A) value of each well was detected by an ELISA reader at a wavelength of 490 nm. The cell survival rate was calculated as follows: Cell survival rate (%) = A value of the experimental group / A value of the control group × 100%. The above experiment was repeated 3 times. The results are shown in the figure. Figure 1 shown.

[0050] from Figure 1 The results show that whether EGFRvIII-22 monoclonal antibody is used alone or in combination with docetaxel, the cell survival rate can be significantly reduced compared with the negative control (P<0.05). Docetaxel, as a chemotherapy drug, inhibits the division and proliferation of cancer cells by interfering with microtubule function. The combination of EGFRvIII-22 monoclonal antibody and docetaxel showed a stronger inhibitory effect, indicating that the two have a synergistic effect in inhibiting cancer cell proliferation.

[0051] Western blot was used to detect protein expression: each group of cells was washed with pre-cooled PBS, protein lysis buffer was added, total protein was extracted, and the protein concentration was determined by Bradford method. 50 μg of protein was taken respectively, and after denaturation, it was electrophoresed through 5% SDS-PAGE concentrating gel and 10% SDS-PAGE separation gel. After electrophoresis, the gel was taken out and transferred to the membrane. The gel was placed in the transfer buffer for equilibration for 20 minutes, and then the protein was semi-dry transferred to the PVDF membrane at 15V for 30 minutes. The membrane was blocked with skim milk powder at room temperature for 90 minutes, and the primary antibody was incubated at 4°C overnight. Horseradish peroxidase (HRP)-labeled secondary antibody was added and incubated at room temperature at 37°C for 1 hour. Equal amounts of ECL colorimetric reagent A and B were mixed and incubated on the PVDF membrane, and the color was developed and photographed. β-actin was used as the internal reference. The results are as follows Figure 2As shown. Wherein, control: negative control group. single6.25: cell group treated with 6.25μg / mL EGFRvIII-22 monoclonal antibody only. single12.5: cell group treated with 12.5μg / mL EGFRvIII-22 monoclonal antibody only. single25: cell group treated with 25μg / mL EGFRvIII-22 monoclonal antibody only. single50: cell group treated with 50μg / mL EGFRvIII-22 monoclonal antibody only. single100: cell group treated with 100μg / mL EGFRvIII-22 monoclonal antibody only. combined6.25: cell group treated with 6.25μg / mL EGFRvIII-22 monoclonal antibody combined with 100nM docetaxel. combined12.5: cell group treated with 12.5μg / mL EGFRvIII-22 monoclonal antibody combined with 100nM docetaxel. combined25: cells treated with 25 μg / mL EGFRvIII-22 mAb combined with 100 nM docetaxel. combined50: cells treated with 50 μg / mL EGFRvIII-22 mAb combined with 100 nM docetaxel. combined100: cells treated with 100 μg / mL EGFRvIII-22 mAb combined with 100 nM docetaxel.

[0052] from Figure 2 The results of Western blot experiments showed that the expression of EGFRvIII protein in the EGFRvIII-22 monoclonal antibody-treated group was significantly different from that in the negative control group (P<0.01). The results of Western blot experiments showed that the expression of EGFRvIII protein in cancer cells treated with EGFRvIII-22 monoclonal antibody was significantly weakened, and it had a certain concentration dependence. However, the combination of monoclonal antibody and docetaxel had little inhibitory effect on EGFRvIII, which also showed that the enhanced effect of the combination of docetaxel and EGFRvIII-22 monoclonal antibody was not achieved by further inhibiting the expression of EGFRvIII protein.

[0053] Clinical trial of EGFRvIII-22, a monoclonal antibody specifically targeting EGFRvIII, for the treatment of cancer

[0054] 1.1 Basic information

[0055] This retrospective study selected 90 patients with non-small cell lung cancer (NSCLC) who were treated in multiple collaborating hospitals between June 2022 and April 2023. The age range of the patients was between 35 and 75 years old, including 55 males and 35 females. The diagnosis of all patients was based on histopathological results and independently confirmed by at least two qualified pathologists. Pathological types included squamous cell carcinoma, adenocarcinoma, large cell carcinoma, and other types of non-small cell lung cancer.

[0056] Inclusion criteria included: 1) aged 18 years or older, regardless of gender; 2) diagnosed with non-small cell lung cancer according to the World Health Organization (WHO) criteria, with a clear pathological type; 3) not having received monoclonal antibody EGFRvIII-22 or other targeted drug treatment; 4) having at least one quantifiable lesion, assessed according to RECIST 1.1 criteria; 5) ASEAN Oncology Group (ECOG) performance status score of 0 to 2 points; 6) expected survival period of more than 3 months.

[0057] Exclusion criteria included: 1) patients with other active malignant tumors or a history of other malignant tumors in the past 5 years; 2) severe complications, such as heart disease, unstable cerebrovascular disease, etc.; 3) pregnant or lactating women; 4) patients with a history of allergy to monoclonal antibody EGFRvIII-22 or its excipients; 5) patients who had participated in other clinical trials or used other experimental drugs within 30 days before the start of this study.

[0058] 1.2 Methods

[0059] In this study, patients in the control group received conventional chemotherapy, and the drug used was docetaxel (produced by Zhejiang Wansheng Pharmaceutical Co., Ltd., with approval number of National Medicine Standard H20051044). The specific dosage was 75 mg / m 2 , by intravenous injection, the duration of 1 hour, once every 3 weeks. The observation group received monoclonal antibody EGFRvIII-22 monoclonal antibody injection treatment, the dose of monoclonal antibody EGFRvIII-22 was 3mg / kg, also by intravenous injection, the injection time was 1 hour, once every 2 weeks.

[0060] This study adopted the solid tumor efficacy evaluation criteria established by the World Health Organization (WHO). The efficacy was determined at four levels: complete remission (CR), partial remission (PR), stable disease (SD), and progressive disease (PD). Complete remission (CR) was defined as the complete disappearance of the original tumor lesions as shown by CT scan, including no necrosis around the lesions, no neovascularization or enhancement lesions. Partial remission (PR) was defined as the lesion necrosis ratio being above 50% but below 99%. The standard for stable disease (SD) was that the lesion necrosis ratio did not exceed 50%. Progressive disease (PD) was characterized by the discovery of new tumor lesions or an increase in the volume of the original tumor on CT scan. This study combined complete remission and partial remission as the standard for effective treatment.

[0061] 1.3 Observation indicators

[0062] In this study, the observation indicators involved clinical efficacy, survival, tumor marker levels, adverse reactions and quality of life evaluation. The efficacy evaluation was mainly based on CT scans at 1, 3, and 6 months after the start of treatment to monitor whether the tumor had progressed or remitted. Survival included overall survival (from the start of treatment to death or the last follow-up) and progression-free survival (from the start of treatment to disease progression or the last follow-up). Before and after treatment, 5 ml of peripheral blood was drawn from the patients, centrifuged at 3500 rpm for 5 minutes, and the supernatant was taken to detect the levels of tumor markers EGFRvIII, CYFRA21-1, and CA125 to evaluate the treatment effect. In addition, during the treatment process, the incidence of adverse development of patients was collected and counted, including nausea and vomiting, alopecia, leukopenia, anemia, and neurotoxicity. The European Organization for Research and Treatment of Cancer Quality of Life Scale (EORTC QLQ-C30) was used to assess the quality of life of patients, with emotional role, physical pain, mental health, physiological role, and social function as indicators. The score range for each item ranged from 0 to 100, and the higher the score, the better the quality of life in the relevant area. Quality of life assessment was performed before and after treatment to fully understand the impact of monoclonal antibody EGFRvIII-22 on patients' quality of life.

[0063] 1.4 Statistical significance

[0064] Statistical analysis was performed using SPSS 22.0 software. All data were tested for normality. Continuous variables were compared between the two groups using the independent sample t test. Categorical variables were compared using the chi-square test. All tests were two-sided, and P < 0.05 was considered statistically significant.

[0065] 2. Results

[0066] 2.1 Baseline characteristics

[0067] This study retrospectively analyzed 90 patients with NSCLC. 45 patients in the observation group received monoclonal antibody EGFRvIII-22 treatment, and 45 patients in the control group received conventional docetaxel chemotherapy. The results showed that there was no statistically significant difference in baseline characteristics between the observation group and the control group (P>0.05), as shown in Table 1.

[0068] Table 1: Baseline characteristics of patients

[0069]

[0070]

[0071] 2.2 Clinical efficacy

[0072] After treatment, the observation group showed significant advantages in overall efficacy. Specifically, in the observation group, 15 patients (33.33%) achieved complete remission (CR) and 20 patients (44.44%) achieved partial remission (PR). In the control group, 10 patients (22.22%) and 18 patients (40.00%) achieved CR and PR, respectively. The total effective rate (CR+PR) of the observation group was 77.78%, which was statistically significant compared with 62.22% of the control group (χ2=4.070, P=0.031), as shown in Table 2.

[0073] Table 2: Comparison of clinical efficacy [n (%)]

[0074]

[0075] 2.3 Comparison of survival

[0076] The median overall survival (OS) of the observation group was 24.36 months, while that of the control group was 20.57 months. The difference was statistically significant (t=3.142, P=0.002). In addition, the median progression-free survival (PFS) of the observation group was also better than that of the control group (observation group: 16.24 months, control group: 12.35 months), which was also significantly different (t=4.678, P<0.001). Figure 3 .

[0077] 2.4 Changes in tumor marker levels

[0078] The changes of EGFRvIII, CYFRA21-1 and CA125 tumor marker levels in the observation group and the control group before and after treatment were shown in Figure 4 Compared with the control group, the observation group showed a decrease in these indicators after treatment, especially EGFRvIII, and the difference reached statistical significance (P<0.05).

[0079] 2.5 Adverse reaction evaluation

[0080] In this study, there was no significant difference in the incidence of adverse reactions such as nausea and vomiting, alopecia, leukopenia, anemia and neurotoxicity between the observation group and the control group (P>0.05), see Table 3.

[0081] Table 3: Comparison of adverse reaction rates

[0082]

[0083] 2.6 Quality of life assessment

[0084] Compared with the control group, the quality of life of the observation group was significantly improved after treatment (P<0.05), especially in terms of emotional function and social function, which increased by 10 points, physical pain decreased by 10 points, and mental health increased by 5 points, as shown in Table 4.

[0085] Table 4: Comparison of quality of life scores

[0086]

[0087]

[0088] 3. Conclusion

[0089] After treatment, the levels of EGFRvIII, CYFRA21-1, and CA125 in the observation group were significantly lower than those in the control group, indicating that monoclonal antibody EGFRvIII-22 treatment may induce tumor cell apoptosis by reducing the levels of these tumor markers, especially the monoclonal antibody EGFRvIII-22 that specifically targets EGFRvIII. Other studies have found that 10% of lung cancer patients treated with monoclonal antibody EGFRvIII-22 did not progress without follow-up treatment after discontinuation of the drug, which highlights the great advantages of immunotherapy. Even after discontinuation of the drug, the patient's immune system can continue to control the growth of tumor cells due to the memory function of the immune system.

[0090] In this study, the efficacy and impact on quality of life of monoclonal antibody EGFRvIII-22 and traditional docetaxel chemotherapy in patients with non-small cell lung cancer (NSCLC) were compared. The results showed that monoclonal antibody EGFRvIII-22 showed better results than traditional chemotherapy in terms of total effective rate, survival and comprehensive improvement of quality of life.

[0091] The data showed that the total effective rate of the observation group was significantly higher than that of the control group (P = 0.031). In addition, the median overall survival (OS) and progression-free survival (PFS) of the observation group were significantly better than those of the control group. These results are consistent with previous clinical trials of PD-1 and PD-L1 inhibitors. This study also evaluated the effect of monoclonal antibody EGFRvIII-22 on tumor marker levels. The tumor markers EGFRvIII, CYFRA21-1, and CA125 in the observation group all decreased after treatment, among which the EGFRvIII level decreased most significantly (P = 0.041).

[0092] Evaluation using the EORTC QLQ-C30 scale showed that patients' scores in emotional function, bodily pain, mental health, etc. improved after treatment with the monoclonal antibody EGFRvIII-22. This result suggests that the monoclonal antibody EGFRvIII-22 not only improves the prognosis of patients, but may also improve the overall quality of life during treatment. This is of great significance for clinical decision-making to expand NSCLC treatment options, because the patient's quality of life is closely related to treatment compliance, satisfaction, and possible long-term health outcomes.

[0093] In terms of safety evaluation, there was no significant difference in the incidence of adverse reactions between the two groups of patients during treatment. Although immunotherapy is associated with specific immune-related adverse events (such as thyroiditis and hepatitis), no significant increase in these events was observed in the study.

[0094] Overall, the results of the study suggest that monoclonal antibody EGFRvIII-22 not only provides more significant clinical benefits in the treatment of non-small cell lung cancer, but may also have a positive impact on the overall quality of life of patients. These findings support the use of monoclonal antibody EGFRvIII-22 as a first-line or second-line treatment for patients with advanced NSCLC and provide valuable reference for clinical practice.

[0095] The embodiments described above are merely descriptions of preferred implementation modes of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A monoclonal antibody EGFRvIII-22 specifically targeting EGFRvIII, characterized in that: It comprises a heavy chain variable region and a light chain variable region; the heavy chain variable region comprises HCDR1, HCDR2 and HCDR3 as shown in SEQ ID NO:1, SEQ ID NO:2 and SEQ ID NO:3, respectively; the light chain variable region comprises LCDR1, LCDR2 and LCDR3 as shown in SEQ ID NO:4, SEQ ID NO:5 and SEQ ID NO:6, respectively.

2. The monoclonal antibody EGFRvIII-22 specific for EGFRvIII according to claim 1, characterized in that: The amino acid sequence of the heavy chain variable region is shown in SEQ ID NO:7, and the amino acid sequence of the light chain variable region is shown in SEQ ID NO:

8.

3. The use of the monoclonal antibody EGFRvIII-22 specifically targeting EGFRvIII as claimed in any one of claims 1 to 2 in the preparation of a pharmaceutical composition for treating cancer, characterized in that: The cancer is lung cancer.

4. The use according to claim 3, characterized in that The lung cancer is non-small cell lung cancer.

5. The use according to any one of claims 3 or 4, characterized in that: The pharmaceutical composition also contains a pharmaceutically acceptable carrier.

6. The use according to any one of claims 3 or 4, characterized in that The pharmaceutical composition is in the form of an injection.

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