Hepatitis C Virus Direct-Acting Antiviral Treatment Adherence Patterns and Sustained Viral Response Among People Who Inject Drugs Treated in Opioid Agonist Therapy Programs

Abstract

Background Adequate medication adherence is critical for achieving sustained viral response (SVR) of hepatitis C virus (HCV) among people who inject drugs (PWID). However, it is less known which patterns of direct-acting antiviral (DAA) treatment adherence are associated with SVR in this population or what factors are associated with each pattern. Methods The randomized three-arm PREVAIL study utilized electronic blister packs to obtain daily time frame adherence data in opiate agonist therapy program settings. Exact logistic regressions were applied to test the associations between SVR and six types of treatment adherence patterns. Results Of the 113 participants treated with combination DAAs, 109 (96.5%) achieved SVR. SVR was significantly associated with all pattern parameters except for number of switches between adherent and missed days: total adherent daily doses (exact AOR=1.12; 95%CI=1.04-1.22), percent total doses (1.09; 1.03-1.16), days on treatment (1.16; 1.05-1.32), maximum consecutive adherent days (1.34; 1.06-2.04), maximum consecutive non-adherent days (.85; .74-.95=.003). SVR was significantly associated with total adherent doses in the first two months of treatment, it was not in the last month. Compared to White participants (30.7±11.8(se)), Black (18.4±7.8) and Hispanic participants (19.2±6.1) had significantly shorter maximum consecutive adherent days. While alcohol intoxication was significantly associated with frequent switches, drug use was not associated with any adherence pattern. Conclusion Consistent maintenance of adequate total dose adherence over the entire course of HCV treatment is important in achieving SVR among PWID. Additional integrative addiction and medical care may be warranted for treating PWID experiencing alcohol intoxication.

Excellent hepatitis C virus cure rates despite increasing complexity of people who use drugs: Integrated‐Test‐stage Treat study final outcomes

“…Other studies in PWUD and the homeless have also reported non-adherence to be associated with non-SVR12. [28][29][30] However, since adherence was self-reported in our study, we accept that this may have underestimated the severity of non-adherence. Use of OAT was also a predictor of SVR12 in our study.…”

The use of technology-based adherence monitoring in the treatment of hepatitis C virus

“… 33 Among those taking only DAAs, overall adherence, consecutive days of doses taken or missed, and adherence in the first 4 and 8 weeks of treatment (but not weeks 8–12) were associated with SVR. 34 …”

“…33 Among those taking only DAAs, overall adherence, consecutive days of doses taken or missed, and adherence in the first 4 and 8 weeks of treatment (but not weeks 8-12) were associated with SVR. 34 Electronic pill boxes Electronic pill boxes, such as the Wisepill ® RT2000 (Cape Town, South Africa), 35 are reusable compartmented pill boxes that wirelessly monitor opening of the outer pill box portion (Figure 4). 35 These are equipped with a SIM card connected to a cellular network and are battery powered.…”

More intensive hepatitis C virus care models promote adherence among people who inject drugs with active drug use: The PREVAIL study

“…The PREVAIL study 2 was conducted in opioid treatment program (OTP) settings to test the effectiveness of three models of HCV care for PWID. The trial showed that higher adherence was associated with successful SVR and the adherence level was highest among participants treated with modified directly observed therapy (mDOT) compared to those treated with groups therapy (GT) or standard individual therapy (SIT) 7 . We examined whether more intensive care models such as mDOT or GT would also increase adherence even among participants with active drug use compared to those without at baseline and during treatment.…”