Their promise is tantalizing: end the HIV epidemic without a vaccine. But how? In an op-ed published this week in The New York Times, two prominent HIV activists and a physician argue “the solution comes in a pill” — albeit a very expensive one.

“Taken daily, Truvada, the brand name for a type of pre-exposure prophylaxis, or PrEP, is up to 99 percent effective at preventing H.I.V. infection,” the op-ed states. “Used as directed, it’s one of the most effective methods of preventing a viral infection ever discovered, as good as the polio vaccine, the miracle of modern medicine.”

The op-ed’s authors — Peter Staley, James Krellenstein and Dr. Aaron Lord — say the problem is not enough of the at-risk population is taking PrEP. They blame “poor policy” and “pharmaceutical price-gouging” for making PrEP “a luxury rather than an imperative,” and they have a plan to change this.

Bottles of antiretroviral drug Truvada are displayed at Jack's Pharmacy in San Anselmo, California on November 23, 2010. Justin Sullivan / Getty Images file

In an interview with NBC News, longtime HIV activist Peter Staley said the plan, aptly dubbed #BreakThePatent, is centered on pushing Gilead Sciences, the manufacturer of Truvada, to either lower the drug’s price or allow a generic manufacturer to sell PrEP in the U.S.

Staley said a national PrEP program could end the HIV epidemic in the U.S. but said it would cost billions of dollars a year unless the price of the drug was significantly reduced.

When Truvada was approved as PrEP in 2012, a month’s supply cost roughly $1,200. The price has inched up in the six years since, and today, the average retail price in a U.S. pharmacy is about $2,000 a month, according to GoodRx. In almost every other country, generic Truvada is available for less than $100 a month. Representatives from Gilead, however, say most Americans on PrEP receive the pills for free by using their insurance and copay assistance cards.

Earlier this year, the Centers for Disease Control and Prevention (CDC) estimated 1.1 million Americans are “at substantial risk for HIV and should be offered PrEP.” While the number of people taking Truvada has increased steadily in the U.S. since it was first approved for prevention purposes, recent data provided by Gilead Sciences estimates just 167,000 people are currently taking the drug.

Those at substantial risk for HIV, according to the CDC, include HIV-negative people in sexual relationships with HIV-positive partners, injection drug users, and men who have sex with men and do not always use condoms. Earlier this week, UNAIDS estimated that globally men who have sex with men are 28 times more likely to acquire HIV than their heterosexual counterparts.

In cities that have robust HIV prevention programs and make PrEP easily accessible — like New York, San Francisco and Washington, D.C. — the number of new HIV diagnoses has consistently decreased since 2012.

New York City overhauled its sexual health clinics and created “HIV one stops,” considered the gold standard in HIV prevention. Instead of delaying the start of PrEP or HIV treatment, a person can walk out of the clinic with a bottle of Truvada the very same day. But Staley said this comes at a cost: New York’s program is borrowing from other health programs, he said, and it is still “busting their budget.”

MARCH-IN RIGHTS

If everyone in that at-risk group were to start PrEP tomorrow, Staley said, new HIV cases would crash, and the epidemic would grind to a halt in the U.S. But he and other activists say they have waited six years since Truvada was first approved for prevention purposes, and so far, less than 10 percent of the people who should be on PrEP are taking the daily pill.

Staley said the idea for the #BreakThePatent movement was spawned a little over a year ago after the Food and Drug Administration made an unexpected decision.

“The FDA shocked all of us by approving Teva Pharmaceutical to make a generic Truvada,” Staley said. “None of us saw that coming, and the FDA was telling us that generic Truvada would be on store shelves within a few weeks.”

But that never happened. In American pharmacies, the only PrEP drug currently available is the one manufactured by Gilead: Truvada.

When the generic never materialized, activists from PrEP4All, the group behind the #BreakThePatent movement, spoke to patent experts and discovered a little-known aspect of the Bayh-Dole Act of 1980, also known as the Patent and Trademark Law Amendments Act. This aspect of the legislation, called “march-in rights,” provides a method for the government to break the exclusivity of a patent.

March-in rights allow the government to require a patent holder “to grant a nonexclusive, partially exclusive, or exclusive license in any field of use to a responsible applicant or applicants” if “such action is necessary to alleviate health or safety needs which are not reasonably satisfied” by the patent holder.

Staley, a co-founder of PrEP4All, said march-in rights could be applied to Gilead, which he said is not reasonably satisfying the need to stem the HIV epidemic.

The federal government and private donors, like the Gates Foundation, footed most of the bill for the research and development that went into PrEP, according to a 2018 report by AVAC, a global HIV advocacy and prevention organization. This is one of the reasons Staley and other activists argue the company should not have the exclusive rights to the drug.

And, since President Trump has said lowering drug prices is one of his “greatest priorities,” and many other politicians on both sides of the aisle have spoken out about drug price inflation, Staley said there may be a window of opportunity to find partners in the current Republican administration, even if it means sticking it to Gilead.

“It’s not lost on AIDS activists that probably the best AIDS president was George W. Bush,” he said, referring to Bush’s signature President’s Emergency Plan for AIDS Relief (PEPFAR) program that provides reduced-price HIV treatments to people in low-income countries around the world.

While three experts told NBC News they had never heard of “march-in rights” being used by the government, James Love, director of Knowledge Ecology International, a nonprofit that works on access to affordable medicine, said “there’s definitely a chance that the tide is going to turn on the march-in issue.”

“It could be this case, it might be the next case, but someone is going to start winning these cases,” Love said.

In a statement provided to NBC News, Gilead Sciences said feedback from patients does not suggestion “cost is a primary obstacle to treatment.”

“The majority of people receiving Truvada for PrEP today who utilize our co-pay coupons pay less than $5 per bottle, and our co-pay assistance program is sufficient to meet the needs of the large majority of people who use it,” according to the statement. “We encourage anyone facing financial difficulties to contact us at www.GileadAdvancingAccess.com.”

The company did not respond to NBC News’ questions regarding the #BreakThePatent movement, Truvada’s price increases and Gilead’s contribution to the research and development funding for PrEP.

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