The STaR study compared the side effects and tolerability of two single-tablet regimens to treat HIV infection: rilpivirine/tenofovir/emtricitabine (Complera) and efavirenz/tenofovir/emtricitabine (Atripla). As one of the study's authors, Calvin Cohen, M.D., M.P.H., explained at ICAAC 2014, unlike other trials STaR tried to determine how participants' side effects during the study compared to those they were already experiencing at baseline. When participants were asked which of the two drugs they would prefer to continue after study completion, "patients were more likely to be enthusiastic if they were on rilpivirine than efavirenz," Cohen said in an interview with TheBodyPRO.com's Myles Helfand.
STaR enrolled 786 treatment-naive patients globally with an HIV-1 RNA > 2,500 copies/mL and randomly assigned them to the Complera or Atripla arm. The cohort was overwhelmingly male (93%) and a majority were white (67%-68% in the two arms), with a median age of 35-37 years. At baseline, mean CD4 counts were 385-396 cells/mm3, and the mean HIV-1 RNA was 4.8 log10 copies/mL, with about two thirds of patients at or below 100,000 copies/mL.
By the 48th study week, 82%-86% of participants had experienced virologic success (HIV-1 RNA < 50 copies/mL), and by week 96 that number had dropped to 72%-78%. Mean CD4 counts changed as follows:
- Week 48: Complera +200 versus Atripla +191 (P = .37)
- Week 96: Complera +278 versus Atripla +259 (P = .17)
However, these figures differed significantly depending on a person's baseline viral load. As Cohen explained, "The higher your viral load is, the more virologic failure there was on rilpivirine versus efavirenz. So rilpivirine is clearly important for people whose viral load is less than 100,000 at baseline."
Complera also performed better in terms of HIV symptoms and quality of life. In every category of HIV symptoms for which there was a statistically significant difference between the two treatment arms, more people on Atripla reported symptoms at week 96 than did those on Complera. For example, 49% of participants in the Atripla arm reported feeling depressed while 38% in the Complera arm reported that feeling.
Interestingly, 30.3% of patients in the Complera arm also reported that the depression they had felt at baseline had lifted by week 96, while 19.1% of those in the Atripla arm reported that their depressive feelings had resolved. Conversely, 14% in the Atripla arm and 7.3% in the Complera arm said that they felt depressed at week 96 when they hadn't had such feelings at baseline. Commented Cohen, "What's interesting is how many people have something at baseline and then feel better. For example, some people are fatigued at baseline. But you were more likely to have less fatigue if you took rilpivirine than efavirenz."
This open-label study was completed before Katie R. Mollan published her analysis of suicidality among patients on efavirenz-containing antiretroviral regimens earlier this year. Mollan had concluded that "initial treatment with an efavirenz-containing antiretroviral regimen was associated with a 2-fold increased hazard of suicidality compared with a regimen without efavirenz." There was, in fact, one suicide in the Atripla arm of the STaR study.
The STaR study also asked participants to complete a questionnaire assessing their quality of life at baseline and at study completion 96 weeks later. Patients' physical health improved significantly in the Atripla arm (physical health composite scores: 0.7 in Complera arm versus 1.7 in Atripla arm), while their mental health improved more in the Complera arm (mental health composite scores: 2.9 in Complera arm versus 0.6 in Atripla arm). Based on week 96 questionnaires, treatment satisfaction among participants was also calculated. The mean treatment satisfaction scale total was slightly higher in the Complera arm (57.3) than in the Atripla arm (56.9) (P = .30).
Fewer people in the Complera arm had adverse events emerge during the course of treatment (89% from baseline to week 48, and an additional 3% between week 48 and week 96) than did those in the Atripla arm (93% between baseline and week 48, and an additional 0.8% from week 48 to week 96).
Now that patients have quite a number of different antiretroviral medications to choose from, the question becomes, "If I have 10 choices of how to suppress the viral load (and maybe I have 20) then how do I pick?" Cohen said. "And picking on the basis of 'I feel good' is one [way to answer this question]," he concluded.