People who inject drugs who are infected with hepatitis C virus can achieve sustained viral response, despite imperfect adherence, according to the results of a new trial.

Although they are at high risk of hepatitis C virus infection and transmission, people who inject drugs tend to be excluded from treatment and coverage of treatment by health insurance because of concerns over adherence to therapy. As this population is most urgently in need of treatment, a team of investigators, led by Elana Rosenthal, MD, assistant professor of medicine in the Division of Clinical Care and Research, at the Institute of Human Virology, of the University of Maryland School of Medicine, in Baltimore, Maryland, set out to evaluate adherence in this population and determine if people who inject drugs are able to achieve cure of hepatitis C virus infection.

For the open-label, nonrandomized observational study—the ANCHOR study (NCT03221309)—Rosenthal and her team evaluated a model of care for the treatment of hepatitis C virus infection in people who inject drugs with chronic hepatitis C virus infection. All patients in the trial are treated with direct-acting antivirals (sofosbuvir/velpatasvir [SOF/VEL] for 12 weeks, dispensed monthly in 28-pill bottles) and are also offered pre-exposure prophylaxis for HIV prevention, as well as buprenorphine for treatment of opioid use disorder when clinically indicated, according to the study design.

Rosenthal sat down with MD Magazine® to discuss the study further (see video).

A total of 160 patients were screened for the trial and 100 were enrolled. The majority of the patients were male (n = 76, 76%), with a median age of 57 years (interquartile range 53-62 years), black (n = 93, 93%) and about half (n = 51, 51%) were unstably housed. More than half (n = 58, 58%) reported daily injection drug use.

Three of the participants were infected with HIV and all 3 were not on treatment for HIV when they started treatment for their hepatitis C virus coinfection. According to Rosenthal, those patients were linked with care for their HIV infection. Two of the patients initiated treatment for HIV, and although 1 did not, his CD4 count was >500c/mL.

“People who have HIV and hepatitis C virus coinfection and in HIV care had already been preferentially treated early on [for their hepatitis C virus coinfection],” Rosenthal explained. “The coinfected people that we saw were not in HIV care. Some of our patients had very low CD4 counts and so we prioritized HIV treatment in those patients.”

After 24 weeks of treatment, Rosenthal and her team found that even with imperfect adherence to treatment, the majority of the participants in the study were able to achieve cure, and the majority had completed all 3 bottles of the treatment (n = 87, 87%). Twenty-one patients had completed the treatment on time (at week 12) and 46 patients completed treatment after week 12.

The team found that having a suppressed viral load (<200 IU/mL) at week 4, was significantly associated with achieving sustained viral response, and about 84 patients achieved this goal. Interestingly, an interruption in treatment did not impact their sustained viral response. Furthermore, although completing the full course of treatment (3 bottles) was associated with sustained viral response (n = 87), so was completing 2 or more bottles (n = 7). Those participants who completed less than 2 bottles did not achieve sustained viral response (n = 6).

Thirteen participants had an interruption in treatment at varying time points in the study period, and these ranged from 3 days to 70 days.

“The most surprising result we had was the number of patients who cured, despite significant nonadherence,” Rosenthal said. “I had 1 patient who completed his medication 5 weeks after week 12, and he still cured. I had a patient who disappeared for 8 weeks and then came back to treatment. He cured. I had a patient with a 70-day interruption. He cured.”

“Our per-protocol sustained viral response was 89%, and I think that is probably more reflective of the sustained in reality because when I look at the patients who are lost-to-follow-up, 7 had undetectable viral load at week 4, 2 had unknown viral load at week 4, and 1 had a detectable viral load at week 4. This leads me to believe that the majority of people who were lost to follow-up were also cured,” Rosenthal continued. She elaborated on these results in her interview (see video).

MD Magazine® asked Rosenthal if the participants’ age had an impact on the results.

“I don’t think patients’ ages impacted the results because we did not really find different outcomes between the men and the women in the study,” she explained. “We were treating patients in Washington, DC, and so [in this region] there are different subgroups of the opioid epidemic. The opioid epidemic that we are seeing now in more rural and suburban areas tends to be a white, younger population. A lot of the patients we are treating [in DC] tend to be from the ‘original’ opioid epidemic that started in the 1970s and 1980s and that tends to be made up of individuals from more urban areas who are ethnic minorities. The people we are seeing are people who have been using heroin for 20, 30, and 40 years already.”

According to Rosenthal, the biggest takeaway from this study is that people who inject drugs should not be excluded from treatment for their hepatitis C virus infection because of concerns regarding treatment adherence. She explained that their findings indicate that there is not a clear factor at the beginning of treatment that should result in a patient being excluded from access to hepatitis C virus infection treatment purely because they are a person who injects drugs.

“The individuals that we were treating in this study were facing so many challenging socioeconomic and demographic factors that, if they can be cured, anyone can be cured,” Rosenthal said. “I think the biggest distinction [among this population] is going to be, interest. If patients are not interested in getting treated, it is unlikely that they are going to take the treatment. However, in anyone who is coming to you and wants to get treated for hepatitis C virus infection, I don’t think having opioid use disorder or ongoing injection drug use should preclude them from being treated and achieving cure. If patients are interested in taking treatment, they can take treatment.”

Data on any reinfections in the population treated are forthcoming; however, Rosenthal explained that if the team ends up seeing reinfections in this population, that indicates they are treating the right population.

“Our goal was to find the people who are actively transmitting [hepatitis C virus]. When you see reinfection, it means you are treating a patient population who continues to transmit the virus,” Rosenthal explained. “That was critical for us: We were not just treating people with hepatitis C virus infection, but we were curing their infection to interrupt transmission to others, and helping to eliminate the epidemic.”

Rosenthal and her colleagues explained that an important component of treating hepatitis C virus infection in people who use drugs and have opioid use disorder is understanding why they have hepatitis C virus infection, and that is their opioid use disorder. Therefore, it is important to address this underlying cause of infection during treatment for their hepatitis C virus infection to improve their overall outcomes (see video).

The study, “High SVR in PWID with HCV Despite Imperfect Medication Adherence: Data from the Anchor Study,” was presented at the 2018 American Association for the Study of Liver Diseases (AASLD) Liver Meeting, November 9-13, 2018, in San Francisco, California.