The trial intends to study the safety and efficacy of Remaxol® (succinate + methionine + inosine + nicotinamide; POLYSAN Ltd., Russia),solution for infusion for the reduction of hyperbilirubinemia in patients with obstructive jaundice caused by tumor (malignancy).

The study will recruit in-hospital surgical patients with obstructive jaundice caused by malignancies of pancreatic and hepatobiliary zone.

The study consists of the following periods:

• Screening - preliminary examination of patients (duration up to 3 days).
• Period of therapy (including surgery and postoperative period) - treatment with the investigational product Remaxol®, solution for infusions, (NTFF POLYSAN Ltd., Russia) or placebo, as part of standard infusion therapy during the postoperative period of patients with mechanical jaundice of malignant origin (duration 10 days).
• The period of follow-up (duration - 3 weeks after the end of treatment).

After the screening, patients who meet the inclusion criteria and do not have exclusion criteria will be randomly assigned to three groups (1:1:1):

• Group I: treatment with Remaxol® 400 ml IV, and placebo (Ringer solution) 400 ml IV, once a day for 10 days, along with standard infusion therapy.
• Group II: treatment Remaxol® 800 ml IV, once a day for 10 days, along with standard infusion therapy.
• Group III: patients will receive placebo ((Ringer solution) 800 ml IV, once a day for 10 days, along with standard infusion therapy.

Assessment will include physical examination data, vital signs, blood tests (CBC, biochemistry - protein, albumin, AST, ALT, APG, GGTP, LDH, total bilirubin, direct bilirubin, amylase, glucose, electrolytes, creatinine, urea, uric acid, C -reactive protein, lipid profile; coagulogram; urine samples), ECOG assessment, repeated abdominal ultrasound, neurophysiological test for the evaluation of encephalopathy, record of bile volume by drainage (if applicable).

All patients will be followed up for 31 days.

Inclusion Criteria:

1. Presence of signed informed consent for participation in the study.

2. Men and women over 18 years of age (incl.).

3. Demonstrated by one or several instrumental methods (ultrasound, cholangiography, CT or MRI) enlargement of intrahepatic bile ducts with visualized obturation of the main bile ducts caused by tumor.

4. Duration of mechanical jaundice less than 30 days, including the first day of the screening period.

5. The status by the classifications Eastern Cooperative Oncology Group (ECOG) scale is 0-2.

6. Life expectancy of more than 3 months.

7. Laboratory data corresponding to the following cutoff limits :

   hemoglobin ≥90 g / l; neutrophils ≥ 1.5x109 / l; Platelets ≥ 75 x 109 / L; AsAT and / or AlAT above 3 х normal but less than 25 х normal Serum creatinine not exceeding 2 × normal, Serum potassium within normal limits

8. Negative urine test for pregnancy in women of reproductive age.

9. For reproductive age: consent to use adequate methods of contraception or for complete abstinence from sexual activity for the period of the study.

Exclusion Criteria:

1. Radical surgery planned within 10 days from the date of randomization.
2. Liver metastases with the biliary block at the level of segmental ducts.
3. Suspicion of metastases in the central nervous system or metastatic arachnoiditis during physical examination; clinically significant ascites.
4. Acute destructive pancreatitis, diffuse peritonitis, ongoing bleeding of any etiology, sepsis (procalcitonin test of 10 ng / ml and above).
5. Liver cirrhosis
6. Presence of clinically significant cardiovascular diseases: chronic cardiac insufficiency III-IV functional class by NYHA, uncontrolled arterial hypertension, acute stroke or acute myocardial infarction in the previous 3 months, unstable angina, uncontrolled arrhythmia and severe heart rhythm disturbances.
7. Pregnancy or lactation.
8. Hypersensitivity to any component of the study drug / placebo and / or intolerance to any component of the study drug / placebo.
9. Regular intake of medications prohibited or not permitted by the study protocol within 4 weeks prior to enrollment or medical indication tio start any medication prohibited or not permitted by the study protocol
10. Concomitant chronic systemic immune or hormonal therapy.
11. Gout.
12. Alcohol and/or drug dependence.
13. Active tuberculosis, HIV infection, syphilis, acute viral hepatitis.
14. Any other conditions / diseases that may interfere with the patient's compliance with the requirements of the Protocol.
15. Mental, physical and other reasons that do not allow the patient to comply with the requirements of the study protocol.
16. Any other significant (by judgement of the investigator) condition that prevents the patient from entering the study.
17. Participation in any clinical trial in the previous 3 months.
18. Staff of the research center and their family members.