Table.
Response During and After Treatment in ION-2
| 12-Week Regimen | 24-Week Regimen | |||
|---|---|---|---|---|
| LDV-SOF (n=109) | LDV-SOF + RBV (n=111) | LDV-SOF (n=109) | LDV-SOF + RBV (n=111) | |
| HCV RNA <25 IU/mL | ||||
| During treatment | ||||
| At 2 weeks | 89 (82%) | 92 (83%) | 89 (82%) | 93 (84%) |
| At 4 weeks | 109 (100%) | 110 (99%) | 108 (99%) | 110 (99%) |
| At the end of treatment | 108 (99%)a | 111 (100%) | 109 (100%) | 110 (99%) |
| After the end of treatment | ||||
| At 4 weeks | 103 (94%) | 107 (96%) | 109 (100%) | 110 (99%) |
| At 12 weeks | 102 (94%) | 107 (96%) | 108 (99%)b | 110 (99%) |
| Virologic breakthrough during treatment | 0 | 0 | 0 | 1 (1%)c |
| Relapse | 7 (6%) | 4 (4%) | 0 | 0 |
HCV, hepatitis C virus; ION-2, Safety and Efficacy of Ledipasvir/Sofosbuvir Fixed-Dose Combination ± Ribavirin for the Treatment of HCV; LDV, ledipasvir; RBV, ribavirin; SOF, sofosbuvir.
One of the 109 patients who received 12 weeks of ledipasvir/sofosbuvir had an HCV RNA level of 42 IU/mL at the week 12 visit but had an undetectable HCV RNA level at the visits occurring at 4, 12, and 24 weeks after the end of treatment.
Among the 109 patients who received 24 weeks of ledipasvir/sofosbuvir, 1 patient withdrew consent after the posttreatment week 4 visit; at this visit, the patients HCV RNA level was less than 25 IU/mL.
This patient did not adhere to the study treatment, as shown by plasma concentrations of ledipasvir and GS-331007 (the predominant circulating metabolite of sofosbuvir) that were below or near the lower level of quantification at weeks 2, 4, and 6 of treatment.
From The New England Journal of Medicine, Afdhal N, Reddy KR, Nelson DR, et al; ION-2 Investigators. Ledipasvir and sofosbuvir for previously treated HCV genotype 1 infection. Volume 370, pages 1483-1493. Copyright © 2014 Massachusetts Medical Society. Reprinted with permission from Massachusetts Medical Society.