Pharmacokinetic and pharmacokinetic/pharmacodynamic characterization of the dolutegravir/rilpivirine two-drug regimen in SWORD-1/-2 phase 3 studies.

AIM: SWORD-1 and SWORD-2 phase 3 studies concluded that switching virologically suppressed participants with HIV-1 from their current three- or four-drug antiretroviral regimen (CAR) to the two-drug regimen of once-daily dolutegravir (DTG, 50 mg) and rilpivirine (RPV, 25 mg) was safe, well tolerated and noninferior for maintaining HIV-1 suppression at week 48 and highly efficacious to week 148. A secondary objective was to characterize drug exposure and exposure-efficacy/safety relationships. METHODS: Adults with plasma HIV-1 RNA <50 copies/mL were randomized to switch to once-daily DTG + RPV on day 1 or to continue CAR for 52 weeks before switching. Trough plasma concentrations (C0) of DTG and RPV, the proportion of participants with HIV-1 RNA <50 copies/mL and adverse events to week 100 were summarized and subjected to exposure-response analyses in the overall population, in the subset of participants who switched from CAR containing enzyme-inducing drugs and by age category (≥50 and <50 years). The relationship between C0avg (individual average C0 across visits) and efficacy/safety was investigated. RESULTS: Although week 2 DTG and RPV C0 were lower in participants switching from enzyme-inducing antiretroviral drugs, C0 and C0avg stayed above in vitro antiviral protein binding-adjusted IC90 and to week 100 with viral suppression >89%. DTG or RPV C0avg showed no relationship with virologic failures or safety. Participants ≥50 years had similar C0avg and safety response to younger participants. CONCLUSION: No clinically relevant relationship between DTG or RPV exposures and virologic or safety response was observed, confirming the DTG + RPV switch for participants as a safe and effective treatment.

Brief Report: Evaluation of Inflammation and Atherogenesis Biomarkers Through 148 Weeks Postswitch to Dolutegravir and Rilpivirine in SWORD-1/SWORD-2.

BACKGROUND: Switching to the 2-drug regimen dolutegravir + rilpivirine demonstrated noninferiority vs continuing a 3-drug or 4-drug current antiretroviral regimen (CAR) at week 48 and maintained high levels of virologic suppression to week 148 in the SWORD studies. We report inflammation and atherogenesis biomarkers postswitch to dolutegravir + rilpivirine. SETTING: SWORD-1: 65 centers, 13 countries; SWORD-2: 60 centers, 11 countries. METHODS: Virologically suppressed adults were randomized to switch to dolutegravir + rilpivirine (early-switch group; n = 513) or continue CAR (n = 511). Participants continuing CAR switched to dolutegravir + rilpivirine at week 52 (late-switch group; n = 477). Biomarkers were evaluated from Baseline to week 48 for dolutegravir + rilpivirine and CAR and noncomparatively for dolutegravir + rilpivirine postswitch through 148 weeks (early-switch) and 96 weeks (late-switch). RESULTS: Through week 48, changes in biomarkers did not significantly differ between dolutegravir + rilpivirine and CAR groups, except for increases in soluble CD14 and decreases in fatty acid-binding protein-2, which favored dolutegravir + rilpivirine. For inflammation biomarkers through week 148, there was no marked change in C-reactive protein, inconsistent changes in soluble CD14 and interleukin-6, and increases in soluble CD163. For atherogenesis biomarkers through week 148, fatty acid-binding protein-2 and soluble vascular cell adhesion molecule-1 showed sustained reductions; D-dimer showed inconsistent increases between early-switch vs late-switch groups. CONCLUSIONS: No consistent pattern of change in biomarkers postswitch to dolutegravir + rilpivirine was observed through weeks 48 and 148 in SWORD-1/SWORD-2, suggesting no association of increased inflammation or atherogenesis with the 2-drug regimen while maintaining virologic suppression.

Fixed-dose combination dolutegravir, abacavir, and lamivudine versus ritonavir-boosted atazanavir plus tenofovir disoproxil fumarate and emtricitabine in previously untreated women with HIV-1 infection (ARIA): week 48 results from a randomised, open-label, non-inferiority, phase 3b study.

BACKGROUND: Dolutegravir is a once-daily integrase strand transfer inhibitor with no need for pharmacokinetic boosting that is approved for the treatment of HIV-1 infection. Because women are often under-represented in HIV clinical trials, we addressed the safety and efficacy of dolutegravir in women with HIV-1. METHODS: The ARIA study is a randomised, open-label, multicentre, active-controlled, parallel-group, non-inferiority phase 3b study done in 86 hospital and university infectious disease clinics, local health clinics, and private infectious disease clinics in 12 countries and one US territory, in North America, South America, Europe, Africa, and Asia. Eligible participants were women aged 18 years or older who had HIV-1 RNA viral loads of 500 copies per mL or greater, had received 10 days or less of previous antiretroviral therapy, and had tested negative for the HLA-B*5701 allele. Pregnant women were excluded. Eligible women were randomly assigned (1:1) to receive either a single-tablet regimen of dolutegravir plus abacavir and lamivudine once a day (dolutegravir group) or a three-tablet combination of ritonavir-boosted atazanavir plus coformulated tenofovir disoproxil fumarate and emtricitabine once a day (atazanavir group). Random treatment group assignment was stratified by plasma HIV-1 RNA viral loads and CD4 cell count at baseline. The primary endpoint was the proportion of participants with HIV-1 RNA viral loads of less than 50 copies per mL at week 48 in all participants who received at least one dose of study medication (intention-to-treat exposed population). We used a non-inferiority margin of -12%. Investigators monitored adverse events to assess safety. This study is registered with ClinicalTrials.gov, number NCT01910402. FINDINGS: Between Aug 22, 2013, and Sept 22, 2015, of 705 women assessed, 499 were randomly assigned to either the dolutegravir group (n=250) or the atazanavir group (n=249); two participants from each group were randomised to treatment but did not receive study medication. At week 48, 203 (82%) of 248 participants in the dolutegravir group compared with 176 (71%) of 247 in the atazanavir group had HIV-1 RNA viral loads of less than 50 copies per mL (mean difference 10·5%, 95% CI 3·1-17·8, p=0·005). One participant in the atazanavir group had nucleoside reverse transcriptase inhibitor-associated resistance that led to reduced emtricitabine susceptibility. Adverse events were similar between the dolutegravir and atazanavir groups; the most common were nausea (46 [19%] of 248 in the dolutegravir group vs 49 [20%] of 247 in the atazanavir group) and headache (28 [11%] vs 32 [13%]). Fewer participants in the dolutegravir group than the atazanavir group reported drug-related adverse events (83 [33%] vs 121 [49%]) or adverse events that led to discontinuation (ten [4%] vs 17 [7%]). One death was reported in each treatment group, but neither was considered related to the study medications. INTERPRETATION: The non-inferior efficacy and similar safety profile of the dolutegravir combined regimen compared with the atazanavir regimen support the use of dolutegravir for HIV-1 infection in treatment-naive women. FUNDING: ViiV Healthcare.