A mathematical model suggests that prescribing a generic version of HIV retroviral Atripla (efavirenz plus tenofovir and emtrictabine) could mean a savings between $200,000 and $1 billion for drug coverage providers in the first year of therapy.
The model, conducted by researchers at Harvard Medical School, was presented July 27, 2012, at the XIX International AIDS Conference in Washington, DC. Atripla has been the Department of Health and Human Services' preferred treatment when initiating antiretroviral therapy, leading researchers to focus on that antiretroviral. The medication boasts long-term efficacy, a safe drug profile, and easy-to-use dosing. In addition, generic versions of its components, and generic forms of other, similarly acting drug components are either available now or are slated for approval within a year.
The generics, which include lamivudine (Epivir, Epivir MBV) to be used in place of emtricitabine (Emtriva) and efavirenz (Sustiva), would be combined with brandname Viread (tenofovir). Viread’s patent is set to expire in 2017.
The cost of Atripla is approximately $2080 per month for a once-daily pill regimen, with a yearly price tag of approximately $15,900. The lifetime cost for Atripla therapy is calculated to be approximately $342,800 in the model.
In addition, patients treated with the generic regimen could expect about 12 years of healthy living, whereas those treated with Atripla therapy could expect only 4 additional months of healthy living, according to the model.
With an estimated 75% price reduction on the generic medications, treatment with brand-name Viread and generic efavirenz and lamivudine would cost $766 per month and $9200 per year. The total savings for the health care system could amount to $920 million in the first year based on those estimates. The lifetime cost for treatment with generic medications was calculated at $300,300, which would save approximately $42,500 per patient.
The actual savings for prescription drug coverage could be more than the model anticipates, according to lead researcher Rochelle Walensky, MD. The model uses a very conservative estimate, and thus has the potential to downplay the cost savings and survival loss.
“A switch from first-line branded to generic antiretrovirals will result in a lifetime average savings of $42,500 [per patient] and a modest survival loss of 0.37 quality-adjusted life years [roughly 4 months],” Dr. Walensky told AidsMeds.com
Even with lower price reductions of 20% of the brand name price, the model still predicts a $200,000 savings in the first year. A 95% price reduction would bring the annual costs down further, saving an estimated $1.1 billion in the first year.
The generic regimen would increase the dosing, however, meaning that patients would need to take 3 daily pills rather than 1 pill. The increased pill burden could lead to poorer adherence and health outcomes, Dr. Walensky noted. In addition, substituting lamivudine with emtricitabine could affect treatment potency, particularly if lamivudine is more likely to cause virus mutations that lead to therapy resistance.
The model presents both ethical and economic questions for the researchers, particularly if the generic treatment offers significant savings but lower treatment efficacy. In addition, the authors also noted that the money saved through generic use might not be marked for HIV care.