With another quarter exceeding analysts’ expectations, Blueprint Medicines has raised its peak sales estimate for rare disease drug Ayvakit to $2 billion.
The Massachusetts biotech unveiled the new target Thursday along with its latest earnings results, which showed that Ayvakit brought in $71 million sales in the fourth quarter. The haul marked a 31% sequential growth and beat Wall Street’s consensus by 8%.
The revenue jump was mainly driven by Ayvakit’s recent expansion into indolent systemic mastocytosis (SM) with an FDA approval in May 2023, Blueprint’s chief operating officer, Christy Rossi, told Fierce Pharma. She didn’t break down the revenue split between indolent and advanced patients, arguing that SM is more of a spectrum of disease than a clear dichotomy.
Blueprint was two full quarters into Ayvakit’s launch in indolent SM before adjusting the peak number from a previous estimate of above $1.5 billion. The chronic subtype of SM represents the majority of the SM population compared with the advanced disease.
The increase didn’t come as much of a surprise given that Blueprint had in January updated its SM market analysis. The number of indolent SM patients in the U.S. who remain uncontrolled with traditional therapy is now estimated at about 9,500, versus 7,500 in Blueprint’s previous calculation. The total SM diagnosis in the U.S. has also risen about 20% year over year to roughly 21,000.
“What we’ve seen over the first couple of quarters very much validates our view of that opportunity, and that we’re on the path,” Rossi said.
Rossi compared Ayvakit’s launch trajectory to that of two other blockbuster rare disease meds, Incyte’s myelofibrosis drug Jakafi and AstraZeneca’s C5 inhibitor Soliris. Although Jakafi’s initial FDA approval happened more than 12 years ago, the drug is still seeing revenue growth despite competitor launches. And as the SM landscape continues to evolve, Rossi said she wouldn’t be surprised if Blueprint in the future dials up Ayvakit’s peak potential even further.
“What you see with these drugs often is that the peak grows because you’re continuing to grow the market as you evolve the launch,” she said.
So far, the number of patients receiving free drugs, patient compliance, treatment duration and international business expansion all look positive, Rossi said.
Ayvakit reached its 1,000 patients in the U.S. in January, compared with about 800 patients as of September. Outside the U.S., Ayvakit got its indolent SM go-ahead from the European Commission in December and treated its first patient in the indication in Germany that month.
Blueprint also continues to grow the number of prescribers across allergists and hematologists as a key strategy for driving Ayvakit’s long-term growth.
“The dynamic that you typically see is that a prescriber will find their first patient and treat that patient, and then that positive experience will enable them to go deeper within their practice and find more patients,” Rossi said.
For 2024, Blueprint expects Ayvakit revenue to come in a range between $360 million and $390 million. At the midpoint, the guidance assumes an 84% year-over-year growth, which is the same as the drug’s revenue growth rate in 2023.
Leerink Partners analyst Andrew Berens, M.D., was less impressed by Blueprint’s 2024 projection. Before Blueprint’s update, his team originally figured Ayvakit could reach nearly $413 million in 2024. Blueprint’s guidance suggests fewer new patients in all of 2024 than those added in the past two quarters since the indolent SM launch, Berens explained to Fierce Pharma.
“We think that’s more of a plateau than expected and makes it hard to see $1.5bn in peak iSM sales without finding many new patients that are candidates for the drug,” Berens said in an email. He figured Blueprint’s internal $2 billion peak sales figure includes $500 million from advanced patients and $1.5 billion from indolent patients.
In addition to Ayvakit, Blueprint also developed Gavreto, which is being returned by Roche because of lower sales expectations. Roche announced the severance in February 2023, and the termination of collaboration is slated to take effect later this month. Blueprint in January unveiled a strategic reprioritization. Besides a couple pipeline cuts, the company also said it’ll wind down Gavreto efforts outside the U.S. and China.
Blueprint has said it won’t bring Gavreto back into the fold and has been looking for a U.S. partner to keep the drug available to patients, and the company in January said it has narrowed down the search to one company.
“We anticipate providing an update, in conjunction with the timing of the termination of the Roche collaboration, which we know will happen by the end of February,” Rossi told Fierce Pharma.
Blueprint is also talking to large companies for a potential partnership around its CDK2 candidate BLU-222, which is being studies in combination with CDK4/6 inhibitors in HR-positive, HER2-negative breast cancer.
Blueprint continues to have “productive discussions” for the agent, Rossi said, pointing to “a lot of strategic interest” in the CDK2 target. She expects the company could potentially pen a deal in the second half of this year before expanding the drug’s clinical development in a meaningful way. Companies that have a portfolio in breast cancer or see breast cancer as a strategic priority are among the parties Blueprint is talking to, Rossi recently told Fierce Pharma in a separate interview.
Editor's Note: The story has been updated with comments from Leerink Partners analyst Andrew Berens, M.D.