Protease-to-integrase switch greatly reduces HIV drug-drug interaction risk, small study finds

About This Study

“Switching to high genetic-barrier integrase inhibitors reduces drug-drug interactions in people living with HIV” was published online on Dec. 19, 2022, in Journal of Acquired Immune Deficiency Syndromes. The lead authors are Ara Askari of Chelsea and Westminster Hospital Foundation Trust in London, UK, and Chhavi Nashier of Imperial College London in London, UK.

Key Research Findings

This Letter to the Editor offered an analysis of a service provided by a multidisciplinary team in London, UK. The goal was to determine the success of switching people living with HIV (PLWH) from boosted protease inhibitors to integrase strand inhibitor-based combinations.

From 2021-2022, 155 PLWH (136 men) were referred to a multidisciplinary team for potential antiretroviral therapy (ART) regimen changes to reduce the risk of interactions with other drugs they were taking. All participants underwent HIV drug resistance testing, with almost 30% of participants showing at least one NRTI resistance mutation.

Ultimately, 95% of participants were offered a second generation integrase inhibitor (62% of switches were to dolutegravir and 38% to bictegravir) combined with two NRTIs. The remaining 5% of participants had too many resistance mutations and remained on boosted protease inhibitors.

Viral suppression rates increased from 91% of participants before changing mediations to 97% of participants after switching ART.

The University of Liverpool HIV interactions website was used to determine the risk of drug-drug interactions (DDIs) and the effectiveness of the changed regimen by evaluating the number of DDIs before and after the switch.

On this website, interactions that are color-coded in red signify that combining the two selected drugs is contraindicated, while amber signifies that special medication management is needed if the two drugs are prescribed for the same patient. In this analysis, a total of 205 red or amber interactions occurred before changing regimens; that total was reduced to 52 potential DDIs after the switch. The most common interaction while on protease inhibitors was with atorvastatin, a cholesterol-lowering medication.

Discussion Highlights and Implications for Practice

Results show that PLWH can be switched to a regimen containing an integrase inhibitor plus NRTIs even if their virus has mutations indicating some NRTI resistance, the study authors wrote. Such a change can significantly expand the pool of medications that may be prescribed for comorbidities, including steroids or chemotherapy. It also reduces the potential for adverse events when medications to lower cardiovascular disease risk, such as statins, are prescribed, they added.

By Barbara Jungwirth