Impact of tamoxifen on vorinostat-induced human immunodeficiency virus expression in women on antiretroviral therapy: AIDS Clinical Trials Group A5366, the MOXIE …

EP Scully, E Aga, A Tsibris, N Archin… - Clinical Infectious …, 2022 - academic.oup.com
EP Scully, E Aga, A Tsibris, N Archin, K Starr, Q Ma, GD Morse, KE Squires, BJ Howell, G Wu…
Clinical Infectious Diseases, 2022academic.oup.com
Background Biological sex and the estrogen receptor alpha (ESR1) modulate human
immunodeficiency virus (HIV) activity. Few women have enrolled in clinical trials of latency
reversal agents (LRAs); their effectiveness in women is unknown. We hypothesized that
ESR1 antagonism would augment induction of HIV expression by the LRA vorinostat.
Methods AIDS Clinical Trials Group A5366 enrolled 31 virologically suppressed,
postmenopausal women on antiretroviral therapy. Participants were randomized 2: 1 to …
Background
Biological sex and the estrogen receptor alpha (ESR1) modulate human immunodeficiency virus (HIV) activity. Few women have enrolled in clinical trials of latency reversal agents (LRAs); their effectiveness in women is unknown. We hypothesized that ESR1 antagonism would augment induction of HIV expression by the LRA vorinostat.
Methods
AIDS Clinical Trials Group A5366 enrolled 31 virologically suppressed, postmenopausal women on antiretroviral therapy. Participants were randomized 2:1 to receive tamoxifen (arm A, TAMOX/VOR) or observation (arm B, VOR) for 5 weeks followed by 2 doses of vorinostat. Primary end points were safety and the difference between arms in HIV RNA induction after vorinostat. Secondary analyses included histone 4 acetylation, HIV DNA, and plasma viremia by single copy assay (SCA).
Results
No significant adverse events were attributed to study treatments. Tamoxifen did not enhance vorinostat-induced HIV transcription (between-arm ratio, 0.8; 95% confidence interval [CI], .2–2.4). Vorinostat-induced HIV transcription was higher in participants with increases in H4Ac (fold increase, 2.78; 95% CI, 1.34–5.79) vs those 9 who did not (fold increase, 1.04; 95% CI, .25–4.29). HIV DNA and SCA plasma viremia did not substantially change.
Conclusions
Tamoxifen did not augment vorinostat-induced HIV RNA expression in postmenopausal women. The modest latency reversal activity of vorinostat, postmenopausal status, and low level of HIV RNA expression near the limits of quantification limited assessment of the impact of tamoxifen. This study is the first HIV cure trial done exclusively in women and establishes both the feasibility and necessity of investigating novel HIV cure strategies in women living with HIV.
Clinical Trials Registration
NCT03382834.
Oxford University Press