Efficacy of Plasmid Elenagen in Combination With Gemcitabine in Patients With Platinum-resistant Ovarian Cancer

Inclusion Criteria: * The patient is 18-70 years old. * Written informed consent of the patient to participate in clinical trials. * Presence of histologically confirmed ovarian cancer. * The return of the disease occurred less than 6 months after the last administration of platinum. * Presence of measurable tumor lesions according to RECIST 1.1 criteria. * Functional status according to ECOG scale is 0-2. * Life expectancy of at least 6 months. * Adequate function of the organs as determined by the following criteria: 1. Absolute number of neutrophils (ANN) ≥1500/mm3 (≥1.5 × 109/l); 2. Platelet count ≥100,000/mm3 (IU: ≥100 × 109/l). 3. Hemoglobin level ≥ 9.0 g/dL determined by analysis performed at least 2 weeks after the last hemotransfusion; 4. The level of AST and ALT in blood serum not exceeding more than 3 times the upper limit of the norm. 5. The level of serum bilirubin not exceeding more than 1.5 times the upper limit of normal. 6. Serum Creatinine ≤ 1.5 mg/dL. * The ability of the patient to follow the directions of the research physician and follow the study regimen. Exclusion Criteria: Criteria by which patients are not included in the study * Platinum-sensitive relapse of ovarian cancer (disease recurrence occurred more than 6 months after the last administration of platinum drugs). * Presence of serious diseases or health conditions: 1. Other malignancies, with the exception of malignancies treated more than 5 years ago without signs of return of the disease. 2. Brain metastases or leptomeningeal metastases. 3. Active infection (e.g. fever ≥38 °C), including active or unresolved pneumonia/pneumonitis. 4. Uncontrolled diabetes mellitus. 5. Myocardial Infarction in the last 12 months, severe/unstable angina, clinically manifested heart failure class III-IV according to the classification of the New York Cardiology Association (NYCA). 6. Gastrointestinal bleeding within the last 2 weeks. 7. Human immunodeficiency virus (HIV), chronic or acute hepatitis B or hepatitis C. 8. Patients with autoimmune disorders or organ transplantation who require immunosuppressive therapy. I. Mental illness that may increase the risk associated with participation in the study or taking the study drug or that may affect the interpretation of the results of the study. K. Polyallergy, bronchial asthma (including aspirin) in history. * Major surgery during the previous 4 weeks (complete wound healing). * Previous chemotherapeutic treatment of the patient according to the scheme GEMCITABINE * Radiotherapy with extended field radiation within the previous 4 weeks or radiotherapy with a limited field radiation within the previous 2 weeks.