Darunavir plus cobicistat demonstrates safety, efficacy in younger, older patients
In the more than 35 years since the start of the HIV epidemic, therapeutic advances and preventive strategies have increased the lifespan of patients with the virus and reduced transmission rates. Evidence regarding the aging process in patients with HIV is growing and suggests that these patients may age differently than people who are not infected with HIV. As a result, examination of clinical outcomes among older patients on ART is warranted, according to the results of a study presented at ASM Microbe 2016.
In a session on ART for prevention and treatment, Kimberley Brown, PharmD, U.S. Medical Director of the HIV portfolio for Janssen, a pharmaceutical company of Johnson & Johnson, reviewed results of a single-arm, phase 3b trial of darunavir plus cobicistat in older (aged > 45 years) vs. younger (aged ≤ 45 years) patients (n = 313). The researchers analyzed the efficacy and safety of 800 mg of darunavir (Prezista, Janssen) and 150 mg of cobicistat (Tybost, Gilead Sciences) plus two nucleoside reverse transcriptase inhibitors.
The majority of patients (94%) were treatment-naive (n = 295) and received a tenofovir disoproxil fumarate-based backbone. Mean baseline HIV-1 RNA levels were 4.83 (0.09) and 4.74 (0.05) log10 copies/mL; mean CD4+ counts were 314.3 (21) and 384.3 (13.5) cells/mm3 in older and younger patients, respectively.
About three-quarters of patients (76%) were aged 45 years and older (n = 239). The majority of the patients were male and Caucasian, according to Brown.
“However, we did have a high number of blacks that were enrolled in this trial, which is not a typical cohort in most trials that we’ve seen,” she said.
Following 48 weeks of treatment with darunavir plus cobicistat, 78.4% of older patients and 81.6% of younger patients had HIV-1 RNA levels of < 50 copies/mL, respectively (95% CI of the difference: -7.4%, 13.8%; P =.540). Mean change in CD4+ count was +186.6 and +190.7 cells/mm3.
The overall incidence of adverse events was similar between older and younger patients (87.8% vs. 92.5%). The rate of grades 2 to 4 adverse events and laboratory abnormalities (grades 3 to 4) were low and generally comparable between both groups, according to the study results. One serious adverse event among the older patients was considered related to the study drug vs. two serious adverse events in the younger group. Rates of discontinuation due to an adverse event were similar between groups (2.7% of older patients vs. 2.9% of younger patients).
The safety and efficacy profiles observed in the study “were generally similar in a younger vs. older age cohort,” Brown said during her presentation. Findings were also “consistent” with what was observed in the ARTEMIS trial of darunavir plus ritonavir (Norvir, AbbVie) among older (aged > 45 years) vs. younger patients, according to the study results.
Brown also discussed the “large number of patients” of all ages taking more than 4 concomitant medications in her conclusion.
“Strategies, including fixed-dose combinations and single-tablet regimens, may reduce poly pharmacy and may be beneficial for both younger and older patients,” she said. – by Julia Ernst, MS
Brown K, et al. Darunavir and cobicistat in older HIV-1-infected patients in a 48-week phase 3 trial. Presented at: ASM Microbe; June 16-20, 2016; Boston.
Disclosure: Brown is an employee of Janssen Pharmaceutical. Please see the full study for a list of all other authors’ relevant financial disclosures.