DURBAN, SOUTH AFRICA – The all-oral, interferon-free, triple- or double-direct-acting antiviral regimens informally known as 3D and 2D proved effective and safe for treatment of chronic hepatitis C due to HCV genotypes 1 and 4 in HIV-coinfected patients taking various antiretroviral combinations in the phase III, multicenter TURQUOISE-1, Part 2 trial, Jürgen K. Rockstroh, MD, reported at the 21st International AIDS Conference.
TURQUOISE-1, Part 2 included 228 patients coinfected with HCV/HIV. Of the 154 with HCV genotype 1a and 44 with genotype 1b, 21 of whom had compensated cirrhosis, 98% of subjects achieved a sustained virologic response (SVR) 12 weeks after conclusion of the 3D regimen, or SVR12, in a modified intent-to-treat analysis. A handful of patients with missing data, or those who stopped treatment for reasons other than virologic failure, were excluded from the analysis.
Bruce Jancin/Frontline Medical News
Dr. Jürgen Rockstroh
In the 28 patients coinfected with HCV genotype 4, none of whom had cirrhosis, the modified SVR12 rate was 100%.
The so-called 3D regimen consists of the NS5A inhibitor ombitasvir coformulated in once-daily, fixed-dose fashion with the NS3/4A protease inhibitor paritaprevir boosted with ritonavir, along with twice-daily dasabuvir, a nonnucleoside NS5B RNA polymerase inhibitor. This combination has received Food and Drug Administration approval and is marketed as Viekira Pak for treatment of HCV genotype 1 in HIV-coinfected patients on the basis of the TURQUOISE-1, Part 1a trial (JAMA 2015;313[12]:1223-32). But this study was confined to 63 U.S. patients, and European investigators wanted to see how 3D worked in a larger, more diverse population, explained Dr. Rockstroh, professor of medicine and head of the outpatient HIV clinic at the University of Bonn (Germany).
In TURQUOISE-1, Part 2, patients with HCV genotype 1a without cirrhosis received 12 weeks of the 3D regimen plus ribavirin, while those with compensated cirrhosis got 24 weeks. Patients with genotype 1b received 12 weeks of 3D without ribavirin, regardless of whether or not they had compensated cirrhosis.
Because dasabuvir is ineffective against HCV genotype 4, those patients got 12 weeks of the 2D regimen – the coformulated ombitasvir/paritaprevir/ritonavir – along with ribavirin.
All subjects were on antiretroviral regimens based upon either darunavir (Prezista), atazanavir (Reyataz), raltegravir (Isentress), or dolutegravir (Tivicay). Nearly all (97%) of the patients had an HIV RNA viral load of less than 40 copies/mL at baseline. Those on ritonavir-boosted antiretroviral therapy discontinued the ritonavir and received it instead via their 3D or 2D hepatitis C therapy.
HIV suppression was well maintained throughout the study. Intermittent episodes of HIV viremia affected 4% of participants, but in all cases the peak was less than 200 copies/mL. None of the episodes met standard criteria for HIV genotypic resistance testing, according to Dr. Rockstroh.
In contrast to the former standard therapy consisting of pegylated interferon and ribavirin, which had an SVR of about 30% in HCV/HIV coinfected patients and was fraught with serious side effects, no one discontinued treatment due to adverse events in TURQUOISE-1, Part 2. No cases of hepatic decompensation occurred. The only serious adverse event deemed possibly treatment related was a single case of depression. Mild fatigue, nausea, diarrhea, insomnia, headache, or itching each occurred in 10%-20% of subjects.
As effective antiretroviral therapy enables HIV-infected patients to have a lifespan approaching normal, HCV coinfection has emerged as a major issue. Roughly one-third of HIV-positive individuals are coinfected with HCV, and the rate of death due to HCV-related liver disease in coinfected patients exceeds the rate of death due to HIV. HCV genotype 1 accounts for three-quarters of chronic hepatitis C in the United States, while genotype 4 predominates in Africa, where the bulk of HIV infections occur.
During the AIDS 2016 conference, the Food and Drug Administration approved Viekira XR, an extended-release coformulation of the 3D regimen. Each tablet contains 200 mg of dasabuvir, 8.33 mg of ombitasvir, 50 mg of paritaprevir, and 33.33 mg of ritonavir. The standard dosing is three oral tablets taken once daily.
The TURQUOISE-1, Part 2 trial was sponsored by AbbVie. Dr. Rockstroh is a consultant to AbbVie and seven other pharmaceutical companies.