Efficacy and Safety of All-Oral Combination of Narlaprevir/Ritonavir and Daclatasvir in Treatment-Naїve Patients With Chronic Hepatitis C Genotype 1b

Inclusion Criteria - Subjects who meet all of the following criteria are eligible for participation in the study: * Are willing and able to provide written informed consent. * Have confirmed chronic HCV infection as documented by: 1. positive anti-HCV antibody (Ab) test or 2. positive HCV RNA or 3. positive HCV genotyping test at least 6 months prior to the Baseline/Day 1 visit. * Have HCV genotype 1b at screening as determined by the Central Laboratory. Any non definitive results must exclude the subject from study participation. * Minimum HCV-RNA level of ≥10,000 IU at baseline. * No evidence of cirrhosis; availability at Baseline of at least one of the following tests, negative results: 1. Liver biopsy within 2 years of screening showing absence of cirrhosis; 2. Fibroscan with a result of ≤ 12.5 kPa within 6 months of baseline/Day1; 3. FibroTest score of ≤ 0.48 AND APRI of ≤ 1 performed during screening. In the absence of a definitive diagnosis of the presence or absence of cirrhosis by the above criteria, a liver biopsy was required. Liver biopsy results supersede the results obtained by Fibroscan or FibroTest. * Have a screening electrocardiogram (ECG) without clinically significant abnormalities (P wave \< 0.1 s; PQ interval 0,12-0,2 s; QRS complex 0,06-0,1 s; QT interval 0,35-0,49 s). * Must have the following laboratory parameters at screening: 1. alanine aminotransferase (ALT) ≤ 10 x the upper limit of normal (ULN); 2. aspartate aminotransferase (AST) ≤ 10 x ULN; 3. Hemoglobin ≥ 12g/dL for male, ≥ 11g/dL for female subjects; 4. Platelets ≥ 50,000cells/mm3; 5. International normalized ratio (INR) ≤ 1.5 x ULN unless subject has known hemophilia or is stable on an anticoagulant regimen affecting INR; 6. Albumin ≥ 3g/dL; 7. Direct bilirubin ≤ 1.5 x ULN; 8. Hemoglobin A1c (HbA1c) ≤ 10%; 9. Creatinine clearance (CLcr) ≥ 60 mL/min, as calculated by the Cockcroft-Gault equation; 10. Have not been treated with any investigational drug or device within 30 days of the screening visit. * A female subject is eligible to enter the study if it is confirmed that she is: 1. Not pregnant or nursing; 2. Of non-childbearing potential (i.e., women who have had a hysterectomy, both ovaries removed, or medically documented ovarian failure, or are postmenopausal women \>50 years of age with cessation \[for ≥12 months\] of previously occurring menses), or 3. Of childbearing potential (i.e., women who had not had a hysterectomy, both ovaries removed, or medically documented ovarian failure). Women ≤ 50 years of age with amenorrhea are considered to be of childbearing potential. These women must have a negative serum pregnancy test at screening and a negative urine pregnancy test on the baseline/Day 1 visit prior to enrollment. They must also agree to one of the following from 3 weeks prior to baseline/Day 1 until 6 months after last dose of the investigational drugs: 1. Complete abstinence from intercourse. Periodic abstinence from intercourse (e.g., calendar, ovulation, sympto thermal, post-ovulation methods) is not permitted Or 2. Consistent and correct use of 1 of the following methods of birth control listed below in addition to a male partner who correctly uses a condom from the date of screening until 6 months after the last dose of the investigational drugs: * intrauterine device (IUD) with a failure rate of \< 1% per year; * female barrier method: cervical cap or diaphragm with spermicidal agent; * tubal sterilization; * vasectomy in male partner; Women of childbearing potential must not rely on hormone-containing contraceptives as a form of birth control during the study. Female subjects using a hormone-containing contraceptive prior to screening must stop their contraceptive regimen use from the date of screening until 6 months after their last dose of investigational drugs. * All male study participants must agree to consistently and correctly use a condom, while their female partner agrees to use either 1 of the non hormonal methods of birth control listed above or a hormone-containing contraceptive listed below, from the date of screening until 6 months after their last dose of investigational drugs: * implants of levonorgestrel; * injectable progesterone; * oral contraceptives (either combined or progesterone only); * contraceptive vaginal ring; * transdermal contraceptive patch; * Male subjects must agree to refrain from sperm donation for at least 6 months after the last dose of investigational drugs. * Are in generally good health as determined by the investigator. * Are able to comply with the dosing instructions for study drug administration and are able to complete the study schedule of assessments. Exclusion Criteria - Subjects with any of the following are not eligible for participation in the study: * Had prior exposure to IFN, RBV, or other approved or experimental DAA targeting the HCV. * Had prior exposure to amiodarone within 24 months before the screening * Are pregnant or nursing female or male with pregnant female partner. * Сhronic liver disease of a non-HCV etiology (e.g., hemochromatosis, Wilson's disease, α1-antitrypsin deficiency, cholangitis). * Are infected with hepatitis B virus (HBV) or human immunodeficiency virus (HIV). * Have history of malignancy diagnosed or treated within 5 years; subjects under evaluation for malignancy are not eligible. * Have chronic use of systemically administered immunosuppressive agents (e.g., prednisone equivalent \> 10 mg/day). * Have clinically relevant drug or alcohol abuse within 12 months of screening. A positive drug screen must exclude subjects unless it can be explained by a prescribed medication; the diagnosis and prescription must be approved by the investigator. * Have excessive alcohol consumption, defined as more than 3 drinks on any single day and more than 7 drinks per week for females, and \> than 4 drinks on any single day and more than 14 drinks per week for males. * Have history of solid organ transplantation. * Have history of clinically significant illness or any other major medical disorder that may interfere with subject treatment, assessment, or compliance with the protocol by Investigators' opinion. * Have history of a gastrointestinal disorder (or postoperative condition) that can interfere with the absorption of the study drug. * Have history of difficulty with blood collection and/or poor venous access for the purposes of phlebotomy. * Usage of any prohibited concomitant medications as described in the protocol (list of drugs with expected drug-drug interactions due to concomitant ritonavir usage) * Have known hypersensitivity to the study investigational medicinal product, the metabolites, or formulation excipients. * Chronic HCV genotype 1b-infected participant who has the presence of genetic variants coding for the NS5A-Y93 С/H/N/S and/or L31 F/M/V/I amino acid substitutions at Screening.