CROI 2015People who are coinfected with HIV and hepatitis C virus (HCV) looking to take the HCV drug Olysio (simeprevir) may need to change HIV medications to avoid drug-drug interactions, Healio reports. Researchers conducted a retrospective chart review of the University of Pittsburgh Medical Center’s HIV/AIDS program between June and October 2014, examining data on 133 coinfected patients. They presented their findings at the 2015 Conference on Retroviruses and Opportunistic Infections (CROI) in Seattle.

Eighty-six percent of the coinfected population examined had genotype 1 of hep C, and 94 percent of the population was taking antiretroviral (ARV) therapy for HIV. Thirty-eight percent of those taking ARVs were on a Norvir (ritonavir)–boosted regimen; 34 percent were taking Sustiva (efavirenz), 11 percent took Isentress (raltegravir), 6 percent Edurant (rilpivirine), 4 percent Tivicay (dolutegravir) and 1 percent elvitegravir/cobicistat.

Seventy-seven percent (103 out of 133) of the individuals had to switch ARVs before beginning treatment with Olysio. Forty-seven of them were able to make a straightforward substitution. Forty needed to consult with an HIV clinician before switching ARVs. Sixteen were not able to switch because of resistance to certain ARVs. More than 30 percent of those taking a protease inhibitor were not able to switch.