Patient-Reported Symptoms over 48 Weeks in a Randomized, Open-Label, Phase 3b Non-inferiority Trial of Adults with HIV Switching to Coformulated Elvitegravir, Cobicistat, Emtricitabine, and Tenofovir DF Versus Continuation of Ritonavir-Boosted Protease Inhibitor with Emtricitabine and Tenofovir DF

BACKGROUND: Coformulated elvitegravir, cobicistat, emtricitabine, and tenofovir disoproxil fumarate (EVG/COBI/FTC/TDF; Stribild(®)) is a recommended integrase inhibitor-based regimen in treatment guidelines from the US Department of Health and Human Services and the British HIV Association. The purpose of this analysis was to determine the change in patient-reported symptoms over time among HIV-infected adults who switch to Stribild(®) versus those continuing on a protease inhibitor (PI) with FTC/TDF. METHODS: A secondary analysis was conducted on the STRATEGY-PI study (GS-US-236-0115, ClinicalTrials.gov NCT01475838), a randomized, open-label, phase 3b trial of HIV-infected adults taking a PI with FTC/TDF who were randomly assigned (2:1) either to Stribild(®) (switch) or continuation of their existing regimen (no-switch). Logistic regressions and longitudinal modeling were conducted to evaluate the relationship of treatment with bothersome symptoms. RESULTS: At week 4 as compared with baseline, the switch group experienced a statistically significantly lower prevalence in five symptoms (diarrhea/loose bowels, bloating/pain/gas in stomach, pain/numbness/tingling in hands/feet, nervous/anxious, and trouble remembering). The lower prevalence of diarrhea/loose bowels, bloating/pain/gas in stomach, and pain/numbness/tingling in hands/feet observed at week 4 was maintained over time. While there were no significant differences between groups in the prevalence of sad/down/depressed and problems with sex at week 4 or week 48, longitudinal models indicated the switch group had a statistically significantly decreased prevalence in both symptoms from week 4 to week 48. As compared with the no-switch group, higher levels of satisfaction with treatment were experienced by patients in the switch group at the first follow-up visit and at week 24. CONCLUSIONS: In this study sample, a switch from a ritonavir-boosted PI, FTC, and TDF regimen to coformulated EVG/COBI/FTC/TDF was associated with more treatment satisfaction and a reduction in the prevalence of patient-reported diarrhea/loose bowel symptoms, which was maintained over the 48-week study period.