By Lisa Rapaport

(Reuters Health) – A cheaper HIV prevention pill is going on sale soon in the U.S., but the price drop won’t help as many people if doctors instead prescribe a newer, more expensive brand-name drug, experts say.

HIV pre-exposure prophylaxis (PrEP), a cocktail of drugs combined in a single pill taken once a day, can reduce the risk of HIV infections from sex or injected drug use by up to 99%, researchers note in the Annals of Internal Medicine. High costs, however, keep many patients who need PrEP from taking it.

A new generic version of Truvada, a PrEP cocktail pill whose patent is expiring, is expected to cost about $8,300 a year, roughly half the current price of Truvada, researchers estimate.

But doctors may instead choose to prescribe a newer brand-name PrEP pill, Descovy, that costs about $16,600 because it may have a lower risk of certain side effects sometimes seen with Truvada including kidney damage and fractures.

“The rush to transition patients to Descovy and the price being charged for that drug are not justified by its possible benefits,” said lead study author Dr. Rochelle Walensky of Massachusetts General Hospital and Harvard Medical School in Boston.

Over five years, researchers calculated that switching 123,610 patients from Truvada to Descovy might prevent 2,101 fractures and 25 cases of advanced kidney failure.

That benefit, however, would be eclipsed by the missed opportunity to get many more patients at high risk for developing HIV – including men who have sex with men and injection drug users – to take PrEP once the generic version makes it more affordable, the study team argues.

It is estimated that 1.2 million Americans are at risk for HIV and eligible for PrEP, the study team writes.

At the current expected price for Descovy, providing PrEP to every one of these people would consume the entire $900.8 million federal budget for HIV prevention, the researchers calculate. If every person got the new generic pill instead, that would free up funds for other HIV prevention efforts, they say.

Both Truvada and Descovy are made by Gilead Sciences. The company didn’t immediately respond to an email seeking comment.

“There should be no difference in effectiveness if the active ingredients are the same,” said Carlos del Rio, an infectious disease at Emory University in Atlanta who coauthored an editorial accompanying the study.

“There may be a slightly better safety profile for Descovy, but efficacy is the same,” del Rio said by email.

SOURCE: and Annals of Internal Medicine, online March 9, 2020.