A Multicenter Open-Label Single-Arm Multi-Cohort Phase I Study of BCD-100 in Patients With Advanced Solid Tumors

Inclusion Criteria: 1. Patient provides a written informed consent and is able to follow the requirements of the Protocol; 2. Age ≥ 18 years 3. Histologically confirmed cancer (well-documented test results; preferably, block specimens available): * unresectable (stage III/IV) or metastatic (stage IV) melanoma (the drug will be used as the first of subsequent therapy lines); * Locally advanced or metastatic NSCLC (squamous cell carcinoma/adenocarcinoma), progressive after at least the first-line therapy (the drug will be used as a second or subsequent therapy lines); * Metastatic clear cell renal carcinoma, progressive after at least the first-line therapy (the drug will be used as a second or subsequent therapy lines); In addition, by investigator's decision, patients with the following malignancies can also be enrolled in the study : * Pleural mesothelioma progressive after at least one therapy line (the drug will be used as a second or subsequent therapy lines); * Metastatic bladder cancer progressive after at least one therapy line (the drug will be used as a second or subsequent therapy lines); * Triple negative breast cancer (ER-, PR-, HER2-) progressive after at least the first-line therapy (the drug will be used as a second or subsequent therapy lines); 4. ECOG score of 0 to 2; 5. Measurable disease (at least one lesion) according to RECIST v. 1.1 ; 6. Resolved toxicity events from the previous therapy or adverse consequences of surgical interventions to ≤ grade 1 CTCAE v. 4.03, except for chronic/irreversible adverse events not affecting the safety of the study therapy (e.g. alopecia); 7. No severe pathology of organs or systems; 8. Life expectancy of at least 12 weeks from the screening; 9. Patients of childbearing potential enrolled in the study must agree to use reliable contraception methods throughout the study period, beginning 2 weeks before the inclusion in the study and up to 8 weeks after the last dose of BCD-100. Exclusion Criteria: 1. Severe concomitant illnesses or life-threatening consequences (including pleural/pericardial/peritoneal effusion that requires medical intervention , pulmonary lymphangitis, or involvement of \>50% renal parenchyma); 2. Brain metastases, progressive or associated with clinical symptoms (e.g. cerebral edema or spinal cord compression). Exclusions: metastases that do not progress and do not require steroids and/or anticonvulsants within at least 4 weeks before randomization ; 3. Severe cardiovascular disorders within 6 months before screening; 4. Autoimmune diseases; 5. Conditions requiring steroids or any other immunosuppressants; 6. Blood disorders: ANC ≤1,500/mm3; platelets ≤100,000/mm3; or Hb ≤90 g/L; 7. Renal function impairment: creatinine ≥1.5 × ULN; 8. Hepatic function impairment: bilirubin ≥1.5 × ULN; AST and ALT ≥2.5 × ULN (5 × ULN for patients with liver metastases), AlkPh ≥ 5 × ULN; 9. Prior anticancer treatment within 28 days before starting the study drug (surgery, radiation therapy , or chemotherapy); 10. Known history of more than 6 lines of systemic anticancer chemotherapy (including neoadjuvant and adjuvant CTs); 11. Prior treatment with anti-PD1/PDL1 agents or CTLA4 inhibitors; 12. Concurrent malignancy except for radically resected cervical carcinoma in situ or radically resected basal cell/squamous cell carcinoma; 13. Conditions limiting patient's ability to follow the Protocol requirements (dementia, neurological or psychiatric disorders, drug or alcohol abuse, etc.); 14. Simultaneous participation in any other clinical trial; participation in other clinical trials within 30 days before inclusion in the present study; previous participation in the present study. 15. Acute infections or active chronic infections; 16. Documented HIV infection; 17. Positive screening results for Hbs-antigen, hepatitis B core antibodies (anti-HBc Ab) and/or hepatitis C antibodies ; 18. Positive results of microprecipitation reaction together with positive TPHA assay results at the screening; 19. Body weight \> 95 kg. 20. Intravenous administration of the drug is impossible; 21. Intravenous administration of contrast agents is impossible; 22. Hypersensitivity to any component of BCD-100. 23. Known history of hypersensitivity to monoclonal antibodies; 24. Pregnancy or breastfeeding;