Early Results Show Doravirine Regimen as Effective as Efavirenz Regimen

At the 2016 Conference on Retroviruses and Opportunistic Infections (CROI) in Boston, early 48-week results showed that the experimental NNRTI doravirine suppressed HIV levels as well as efavirenz (Sustiva) but with lower rates of side effects. No NNRTIs are currently listed as a "recommended" starting regimen in the federal Guidelines. Efavirenz was recently moved to "alternative" due to its side effects and another "alternative" NNRTI, rilpivirine, should only be used if starting treatment with a viral load <100,000 copies.

This study evaluated viral suppression <200 copies and <40 copies for those who were new to HIV treatment with starting viral loads below and above 100,000 copies. Earlier study in the lab showed that doravirine is effective against common NNRTI-resistant strains.

A total of 216 people were divided into two groups and took either doravirine or efavirenz with tenofovir/emtricitabine (Truvada). Four out of five were white, 93% men, and average age was 36 years. Average CD4 count was about 440. Average viral load was around 40,000 copies with 35% having viral loads >100,000. Both regimens were taken once a day with or without food.

At 48 weeks, no data were given for changes in CD4 counts, but 77.8% of those on doravirine and 78.7% on efavirenz achieved viral loads <40 copies. Also, no data were given on suppression of HIV in those who started with viral loads >100,000 copies.

No one stopped the study due to drug side effects, and severe side effects occurred in 6.5% (doravirine) and 8.3% (efavirenz) of people. Overall drug side events were less common in those who took doravirine (31.5%) compared to those on efavirenz (56.5%). Common side effects included: diarrhea (0.9% doravirine, 6.5% efavirenz), nausea (7.4%, 5.6%), dizziness (6.5%, 25.9%), headache (2.8%, 5.6%), abnormal dreams (5.6%, 14.8%), insomnia (6.5%, 2.8%), nightmares (5.6%, 8.3%) and sleep disorder (4.6%, 6.5%). Three people on doravirine and six on efavirenz stopped the study for other reasons.

Source

GM Gatell, et al, "Doravirine 100mg QD vs Efavirenz + TDF/FTC in ART-Naive HIV+ Patients: Week 48 Results". 2016 CROI, Boston, MA.