HIV/AIDS · White paper
HIV/AIDS Clinical Trials
Approved therapies, the pivotal-trial endpoints they were judged on, the magnitude of benefit — and the drugs that failed their endpoints, and why.
Indication overview
About hiv/aids — and why its trials are hard
HIV attacks CD4 T-cells and, untreated, progresses to AIDS, defined by CD4 counts below 200 cells/mm3 or opportunistic infections. Although no cure exists, combination antiretroviral therapy (ART) has transformed HIV into a manageable chronic condition, suppressing plasma HIV-1 RNA to undetectable levels, restoring immune function, and preventing transmission (undetectable = untransmittable). An estimated 38.4 million people were living with HIV worldwide as of 2021. Modern regimens are dominated by single-tablet and long-acting combinations built from integrase inhibitors, NRTIs, and NNRTIs. Clinical trials center on virologic suppression at weeks 24 and 48, CD4 recovery, resistance, tolerability, and adherence, with growing use of long-acting formulations and pre-exposure prophylaxis (PrEP). Regulatory success typically requires demonstrating non-inferior or superior viral suppression versus an established regimen in diverse populations. Remaining challenges include reservoir persistence, drug resistance, comorbidity management in an aging population, and the unmet goal of a functional cure or an effective preventive vaccine.
Approved therapies & pivotal evidence
What's been approved — and by how much it moved the endpoint
| Drug (brand) | Approved | Setting | Pivotal trial | Primary endpoint | Magnitude of benefit |
|---|---|---|---|---|---|
| Bictegravir/emtricitabine/tenofovir alafenamide (Biktarvy) | 2018 | Once-daily single-tablet regimen for HIV-1 (treatment-naive and virologically suppressed) | GS-US-380-1489/1490 (NCT02607930) | HIV-1 RNA <50 copies/mL at week 48 | Non-inferior high rates of virologic suppression (~90%+); no treatment-emergent resistance observed |
| Dolutegravir/lamivudine (Dovato) | 2019 | Two-drug complete regimen for treatment-naive adults | GEMINI-1/2 (NCT02831673/NCT02831764) | HIV-1 RNA <50 copies/mL at week 48 | Non-inferior to 3-drug dolutegravir + TDF/FTC (~91% suppression) |
| Dolutegravir/abacavir/lamivudine (Triumeq) | 2014 | Once-daily single-tablet regimen (HLA-B*5701-negative) | SINGLE (NCT01263015) | HIV-1 RNA <50 copies/mL at week 48 | Superior to efavirenz/TDF/FTC (~88% vs ~81% suppression) |
| Emtricitabine/tenofovir disoproxil fumarate (Truvada) | 2004 | Backbone for treatment; approved for PrEP in 2012 | iPrEx (NCT00458393, PrEP) | Viral suppression (treatment); HIV incidence reduction (PrEP) | PrEP reduced HIV acquisition ~44% overall, >90% with high adherence |
| Cabotegravir/rilpivirine (long-acting injectable) (Cabenuva) | 2021 | Long-acting maintenance in virologically suppressed adults | ATLAS/FLAIR (NCT02951052/NCT02938520) | HIV-1 RNA <50 copies/mL maintenance | Non-inferior to daily oral ART with monthly/every-2-month dosing |
| Efavirenz/emtricitabine/tenofovir DF (Atripla) | 2006 | First once-daily single-tablet regimen | Study 934 / GS-01-934 | HIV-1 RNA suppression and CD4 increase at week 48 | Durable suppression; efavirenz limited by neuropsychiatric effects |
Where trials have failed
Drugs that missed their endpoint — and what contributed
The most instructive lessons in hiv/aids development come from programmes that failed the endpoint that mattered.
| Drug / trial | Endpoint outcome | What contributed |
|---|---|---|
| Merck Ad5 HIV-1 vaccine (V520/MRKAd5) — STEP study / HVTN 502 (NCT00095576) | Halted early for futility; no protection and a signal of increased HIV acquisition in some Ad5-seropositive/uncircumcised men | Cell-mediated (T-cell) vaccine could not prevent infection; pre-existing Ad5 immunity |
| ALVAC/gp120 vaccine regimen — HVTN 702 (Uhambo, NCT02968849) | Stopped for futility; no reduction in HIV infections versus placebo | Modest, non-durable immune responses; failed to replicate RV144 signal in a high-incidence setting |
| Bivalent gp120 vaccine (AIDSVAX B/E) — VAX003/VAX004 | Failed to prevent HIV infection | Antibody-only gp120 approach did not generate protective neutralizing immunity |
Choosing the right endpoint
Primary endpoints that matter in hiv/aids trials
- Plasma HIV-1 RNA suppression (<50 copies/mL) — Primary efficacy endpoint; FDA snapshot analysis at week 48 (with week 24 support)
- CD4+ T-cell count recovery — Marker of immune reconstitution and reduced opportunistic-infection risk
- Emergence of resistance mutations — Treatment-emergent resistance signals durability and regimen robustness
- Safety, tolerability and adherence — Critical for lifelong therapy; drives long-acting formulation development
- HIV incidence (prevention/PrEP trials) — New infections versus comparator; endpoint for preventive agents and vaccines
How iNGENū runs hiv/aids trials
Physician-led design, built for FDA submission
Endpoint & biomarker strategy
Board-certified specialists design endpoints and patient selection aligned to current FDA guidance for this indication.
FDA-ready data
Built to ICH-GCP and 21 CFR 312.120, with direct FDA submission — data accepted by the FDA, EMA and MHRA.
Faster, lower-cost delivery
~4-week ethics via the TGA CTN scheme, up to 43.5% R&D rebate, and 80–90% below US CRO cost.
The full white paper: approved-product analyses, pivotal endpoints and trial-design strategy. Open-access · no sign-in.
Frequently asked questions
HIV/AIDS clinical trials — FAQs
What is the main efficacy endpoint in HIV treatment trials?
Is there a cure for HIV?
Why have HIV vaccines repeatedly failed?
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