Reddy KR, et al. - The long-term efficacy and safety of daclatasvir-based regimens administered during clinical studies were assessed in this study. In 99% of recipients of daclatasvir-based regimens, sustained virologic response (SVR)12 was durable. Hepatic disease progression and new hepatocellular carcinoma were rarely observed. Among non-responders, emergent non-structural protein-5A (NS5A) substitutions persisted longer than non-structural protein-3 (NS3) substitutions.

• The researchers recruited patients within 6 months of parent study completion or protocol availability, at the study sites.
• Durability of SVR at follow-up Week 12 (SVR12) was the primary objective.
• Analyzing HCV sequences in non-responders or responders who relapsed, and characterization of liver disease progression were included as secondary objectives.

• The researchers enrolled and began following 1503 recipients of daclatasvir-based regimens (follow-up cut-off, 13-October-2015) between 24-February-2012 and 17-July-2015.
• In this study, 60% were male, 18% aged ≥65 years, 87% had genotype-1a (42%) or -1b (45%) infection, and 18% had cirrhosis.
• Median follow-up from parent study follow-up Week 12 was 111 (range, 11-246) weeks.
• Out of 1489 evaluable patients, 1329 were SVR12 responders; 1316/1329 maintained SVR until their latest visit.
• 12 responders relapsed by (n=9) or after (n=3) parent study follow-up Week 24; 1 was reinfected.
• Relapse occurred in 3 out of 842 (0.4%) and 9 out of 487 (2%) responders treated with interferon-free or interferon-containing regimens, respectively.
• They diagnosed hepatic disease progression and new hepatocellular carcinoma in 15 and 23 patients, respectively.
• Emergent non-structural protein-5A (NS5A) and -3 (NS3) substitutions were replaced by wild-type sequences in 27/157 (17%) and 35/47 (74%) patients, respectively among non-responders.