People with HIV who switch from a stable antiretroviral (ARV) regimen to Delstrigo (doravirine/tenofovir disoproxil fumarate/lamivudine) had a high rate of full suppression of the virus at the three-year mark in a large Phase III clinical trial.

Princy Kumar, MD, of Georgetown University, presented findings from the open-label, randomized, active-controlled, noninferiority DRIVE-SHIFT trial at the virtual HIV Drug Therapy Glasgow meeting.

Delstrigo contains the relatively new non-nucleoside reverse transcriptase inhibitor (NNRTI) Pifeltro (doravirine), which, like Delstrigo, was approved in September 2019.

The DRIVE-SHIFT study recruited people with HIV who were taking two nucleoside/nucleotide reverse transcriptase inhibitors plus a boosted protease inhibitor, boosted Vitekta (elvitegravir) or an NNRTI. All the participants needed to have sustained a fully suppressed viral load for at least six months prior to enrolling in the trial.

The participants were randomized on a two-to-one basis to switch to Delstrigo on day 1 of the study (the immediate switch group) or week 24 (the delayed switch group).

Those who remained in the study at the 48-week mark could enter the extension period, which continued through week 144. The 48-week results were presented at the 2018 IDWeek meeting.

The new analysis of the trial presented at the Glasgow conference included 656 participants who switched to Delstrigo. At week 144, 2.7% (12 of 438) of those in the immediate switch group and 4.8% (10 of 209) of those in the delayed switch group had a viral load of 50 or higher.

The average increase in CD4 count by week 144 was 40 cells in the immediate switch group and 56 cells in the delayed switch group.

A respective 2.1% (9 of 438) and 3.3% (7 of 209) of those in the immediate and delayed switch groups experienced virologic failure. Drug resistance testing conducted on the virus of four of these 16 individuals indicated that none had developed viral mutations associated with resistance to any of the three ARVs in Delstrigo.

The participants experienced a reduction in their fasting lipid levels during the first 24 weeks following switching to Delstrigo; they maintained this reduction through week 144.

In the immediate and delayed switch groups, the median weight increase was 3.1 pounds and 2.7 pounds, respectively.   

The most common adverse health events were the common cold (16.2%), headache (12.3%) and diarrhea (9.1%). A total of 4.1% of the participants discontinued Delstrigo due to adverse health events. None of the participants died.

The study authors concluded that Delstrigo is a “generally well-tolerated option for maintaining viral suppression in adults considering a change in therapy.”