Background: IFN-based treatment of chronic hepatitis C has demonstrated a late relapse rate of <5%, usually occurring within 2 years of treatment. While high rates of SVR12 weeks after completion of directly-acting antiviral combinations has been established, data on long-term durability of SVR achieved through IFN-free regimens are lacking. The objective of this analysis was to analyze data from multiple studies utilizing IFN-free DAA-based regimens to define the durability of SVR and evaluate for associated changes in biomarkers related to liver and metabolic fitness.
Methods: Data on patients who achieved SVR12 from the following clinical trials were included: SPARE (HCV monoinfected, SOF+ RBV x 24 wks, n=38); SYNERGY (HCV monoinfected, SOF/LDV x 12 wks, n=20, SOF/LDV + GS-9669 X 6 weeks, n=19, SOF/LDV + GS-9451 X 6 weeks n=19) and ERADICATE (HIV/HCV coinfected, SOF/LDV X 12 weeks, n=49). HCV viral loads and serum biomarkers were collected up to SVR108. HCV viral loads were measured with Abbott M2000 RealTime HCV assay, with a limit of quantification of <12 IU/mL.
Results: Of 138 patients followed for a period ranging from 1 to 96 weeks (averaging 35 weeks) post SVR12, 138 patients (100%) maintained HCV viral loads at <12 IU/mL (Table 1) with no current evidence of late relapse. At SVR12 timepoint, 86% of patients had ALT within normal range. At the current furthest timepoint, averaging 35 weeks after SVR12, 91% of patients had ALT within normal range.
Conclusions: This study shows the long-term durability of SVR associated with DAA-based therapy during ongoing assessment of up to 2 years. While the rise in percentage of ALT within normal range over the average follow up period was minimal, it may suggest an association with SVR durability. It is plausible that this change reflects the long-term histologic regression of necroinflammation and fibrosis described in patients who achieve SVR. Ongoing data collection including liver biopsy and radiologic studies are underway to continue analysis of this novel population.
| WEEKS POST SVR12 (WEEKS) | 0 | 12 | 24 | 36 | 48 | 60 | 72 | 84 | 88 | 96 | |
| SVR (WEEKS) | SVR12 | SVR24 | SVR36 | SVR48 | SVR60 | SVR72 | SVR84 | SVR96 | SVR100 | SVR108 | |
| HCV VL<12/N | 138/138 | 112/112 | 84/84 | 36/36 | 27/27 | 26/26 | 25/25 | 11/11 | 3/3 | 1/1 | |
| % SVR | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% |