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Analysts believe that Gilead’s new PrEP drug Yeztugo could reach peak sales of $4.5 billion. Not if GSK has anything to say about it.
Gilead is mounting a bid to tighten its grip on the HIV market. Having
secured
approval for twice-yearly HIV prevention product Yeztugo, the company has a shot at wresting more market share from GSK and generics manufacturers.
HIV products
generated
$19.6 billion for Gilead last year. Biktarvy, a once-daily pill for treating HIV, is the cornerstone of the portfolio, generating $13.4 billion in 2024. Descovy, a once-daily drug to treat and prevent HIV, is Gilead’s other main HIV product. The company reported $2.1 billion in Descovy sales last year, most of which came from its use in HIV prevention.
Descovy competes with GSK’s Apretude, an injectable preventive given every two months, in the pre-exposure prophylaxis (PrEP) market. Talking on an earnings call in April, Johanna Mercier, Gilead’s chief commercial officer,
said
Descovy maintained an “over 40% market share and grew more than 2% year-over-year.”
An HIV doctor told Mizuho analysts that 45% to 50% of their 125 PrEP patients are on Descovy. One-third of the doctor’s patients take Apretude, although the analysts said the average could be 20% to 25% in the northeast U.S. and varies with the commercial insurance rates of individual practices. Around 20% of patients take Truvada, Gilead’s old PrEP drug, or generic copies of the off-patent molecule.
Yeztugo’s Path to $4.5B Peak Sales
The analyst consensus is that Yeztugo will achieve peak sales of around $4.5 billion. Talking at a Goldman Sachs event in June, Gilead CEO Daniel O’Day
outlined
three pools of patients the big biotech will target as it seeks to grow Yeztugo sales.
First, the company will seek to convert the 400,000 to 450,000 current PrEP users in the U.S. to Yeztugo, O’Day said. The new drug could improve treatment compliance, which O’Day said is around 50% for daily pills.
The HIV doctor expects Yeztugo to be popular with current PrEP users, telling Mizuho analysts the “vast majority” of Apretude users and the “majority” of daily oral PrEP users could switch to the new drug. Up to 10% of the doctor’s patients may want to stay on an oral regimen because of needle aversion. Another doctor Mizuho spoke with, however, was more conservative, estimating that just 30 to 40% of their private practice PrEP patients will switch.
If the first doctor is right, Yeztugo will rapidly reshape the PrEP market. That doctor said “most” patients who want to switch to Yeztugo will be able to do so within 12 months. O’Day has predicted Yeztugo will have 70% to 75% payer coverage after six months, rising to 90% by the end of the drug’s first year on the HIV market.
Gilead’s second group of target patients is the 750,000 to 800,000 people in the U.S. who could benefit from PrEP but do not currently take a drug to prevent HIV. O’Day said most PrEP users are men who have sex with men who live in large urban areas. Gilead has been less successful at reaching other groups of at-risk individuals, O’Day said.
The company will target the current and potential U.S. PrEP patients from the start of the Yeztugo launch. The HIV doctor said some patients, mainly men who have sex with men, who do not currently take a PrEP drug have contacted them about Yeztugo. O’Day said it will take time to raise awareness and drive demand among underserved communities.
Gilead’s third group of patients is a longer-term play. PrEP is largely a U.S. phenomenon today, O’Day said, but Gilead believes Yeztugo represents good value to payers in other countries. Preventing a case of HIV in the U.S. saves about $1.1 million in eventual lifetime healthcare costs, according to the CEO. Gilead plans to talk to health ministries about programs where Yeztugo could serve targeted populations.
GSK Gears Up for Market Share Fight
The anticipated reshaping of the PrEP market is a threat to one of GSK’s growth drivers. Developed by the U.K. pharma’s HIV joint venture ViiV Healthcare, Apretude sales rose around 90% last year to hit 279 million pounds ($383 million). A wholesale switch to Yeztugo, as the HIV doctor foresees, could cause Apretude sales to contract.
GSK sees things differently. ViiV Chairman David Redfern
said
on an earnings call in February that the company “certainly [expects] Apretude to continue to grow this year,” arguing that the market is still “significantly underdeveloped” and that the launch of another long-acting PrEP drug will “help grow the market for all of us.” Redfern also expects some patients to prefer Apretude to Yeztugo.
“The competitive product definitely won’t be for everyone,” Redfern said. “We now know that there’s quite a high frequency of nodules that people experience in their abdomen, where the two injections are given. For potential PrEP users who are body image conscious, which will be quite a proportion of them, I think that potentially is an issue.”
Given the relative size of the HIV treatment and prevention markets, GSK could still have a big franchise even if Gilead starts dominating the PrEP sector. Redfern has valued the total HIV market at 22 billion pounds ($30.2 billion), with treatments accounting for 90% of all sales. Gilead’s Mercier said Biktarvy has a 51% share of the U.S. treatment market but GSK is advancing molecules to challenge the incumbent.
GSK’s pipeline includes VH184, an integrase strand transfer inhibitor the company said has the best resistance pro to date, and broadly neutralizing antibody N6LS. Those drug candidates, plus the capsid inhibitor VH499, are part of GSK’s plans to launch a twice-yearly HIV treatment between 2028 and 2030. GSK is aiming to launch a twice-yearly PrEP drug, matching the Yeztugo regimen, in the same timeframe.
While GSK is seeking to use its long-acting injectable capabilities to win market share, Gilead is also moving next-generation candidates through the clinic. Gilead has 12 clinical programs in HIV lined up to help defend its empire through potential launches including a once-yearly version of the active ingredient in Yeztugo.