Long-acting injectable cabotegravir not cost-effective for HIV PrEP
While the long-acting injectable form of cabotegravir has shown superior effectiveness for HIV pre-exposure prophylaxis (PrEP), a cost-effectiveness analysis found that the drug is too expensive at its current price compared to the daily oral medication available as a generic.
A cost-effectiveness analysis found that the long-acting injectable form of cabotegravir (CAB-LA) is too costly at its current price versus generic daily oral emtricitabine-tenofovir disoproxil fumarate (F/TDF) for HIV pre-exposure prophylaxis (PrEP).
In 2020, the international HIV Prevention Trials Network 083 trial was unblinded early after demonstrating the superior effectiveness of CAB-LA versus F/TDF for HIV PrEP. In the current analysis, researchers used the Cost-Effectiveness of Preventing AIDS Complications model to simulate a population of about 476,000 men who have sex with men and transgender women prescribed PrEP with similar risk factors for HIV as the U.S. trial participants (mean age, 30.1 years). They modeled four strategies: no PrEP, generic F/TDF, branded emtricitabine-tenofovir alafenamide (F/TAF), and CAB-LA. Using a 10-year planning horizon, they assessed several outcomes, including primary transmissions, quality-adjusted life-years (QALYs), and health care costs in 2020 U.S. dollars. Results were published Feb. 1 by Annals of Internal Medicine.
Over 10 years, costs would total $33.48 billion for no PrEP, $30.67 billion for generic F/TDF, $60.42 billion for branded F/TAF, and $75.84 billion for CAB-LA (assuming the upper bound of its price), inclusive of primary transmissions, the study found. Compared with generic F/TDF and branded F/TAF, CAB-LA increased life expectancy by 28,000 QALYs and 26,000 QALYs, respectively, among those at very high risk for HIV. The researchers concluded that CAB-LA might be considered cost-effective if it were priced at about $6,600 per year above generic F/TDF, which costs about $360 per year. At 10 years, the study found that CAB-LA could achieve an incremental cost-effectiveness ratio of at most $100,000 per QALY compared with generic F/TDF at a maximum price premium of $3,700 per year versus generic F/TDF (CAB-LA price <$4,100 per year). Branded F/TAF cost more per QALY gained than generic F/TDF compared with no PrEP.
The results indicate that the “incremental clinical benefits of CAB-LA would not justify a large price difference compared with F/TDF,” the study authors wrote. They assumed a stable number of primary transmissions over time and lacked data to incorporate potential changes in quality of life while receiving oral or long-acting PrEP, among other limitations.
The study should lead to future research on nuanced mixed uses of generic F/TDF and CAB-LA across populations at various levels of HIV risk over time, an accompanying editorial noted. “[The] analysis yields important findings about the economic aspects of long-term injectable PrEP and sets the groundwork for addressing questions of pressing policy, programmatic, and social justice import,” the editorialists wrote.