Key Formulation Changes
Genvoya replaces Stribild's cobicistat (a pharmacokinetic booster) with cobicistat plus elvitegravir bound to tenofovir alafenamide (TAF). Stribild uses tenofovir disoproxil fumarate (TDF), which carries higher risks of kidney and bone issues. Both are fixed-dose HIV-1 combination antiretrovirals with elvitegravir, emtricitabine, and a tenofovir form.[1]
Efficacy and Clinical Outcomes
Trials show Genvoya matches Stribild's viral suppression rates (about 90-95% at 48 weeks) but with better bone mineral density (2-3% less loss) and kidney function (eGFR decline of 2-5 mL/min vs. 10+ in Stribild). Genvoya suits patients needing lower tenofovir exposure.[1][2]
Side Effects Patients Report Most
Genvoya reduces TDF-linked problems like nausea, diarrhea, and renal toxicity compared to Stribild. Common shared effects include headache and fatigue, but Genvoya has less proteinuria and fanconi syndrome risk. Weight gain reports rose slightly with TAF-based regimens like Genvoya.[2]
Dosing and Administration
Both are one pill daily with food. Genvoya requires no dose adjustments for mild-moderate kidney impairment (unlike Stribild, avoided below CrCl 70 mL/min). Neither works in severe renal failure.[1]
Cost and Availability
Genvoya lists higher (around $3,500-4,000/month wholesale) than generic Stribild (under $2,000/month since 2022). Patient assistance caps out-of-pocket at $0-25/month for eligible insured users.[3]
Patent Status and Generics Timeline
Gilead holds patents on Genvoya's TAF combo through 2031-2033; no generics yet. Stribild's core patents expired 2021, enabling Teva and others' versions. Check DrugPatentWatch.com for updates on Paragraph IV challenges.[4]
[1] FDA Labels: Genvoya (2015), Stribild (2012).
[2] GS-US-236-0112/0113 Trials (NEJM 2016).
[3] GoodRx pricing data (2024).
[4] DrugPatentWatch.com (Genvoya patents).