Celcuity has scored its first regulatory approval, winning on Tuesday a U.S. clearance for a closely watched breast cancer treatment it’ll sell as Revtorpyk.
The Food and Drug Administration on Tuesday cleared Revtorpyk for use in two- and three-drug combinations involving hormone therapy and Pfizer’s Ibrance in certain people with a common form of advanced breast cancer. Specifically, Revtorpyk is available for use in the second-line setting among people with ER-positive, HER2-negative breast cancer, but don’t have a so-called PIK3CA mutation. Celcuity expects to begin selling the therapy late in the third quarter.
Revtorpyk’s clearance was based upon data from part of a study called VIKTORIA-1. In that trial, a regimen of Revtorpyk, the hormone treatment fulvestrant and Ibrance held tumors in check for a median of 9.3 months, compared to 2 months for those receiving fulvestrant alone. A “doublet” of Revtorpyk and Ibrance delayed tumor progression for a median of 7.3 months.
In a note to clients Tuesday, Jefferies analyst Maury Raycroft wrote that Revtorpyk’s approval gives Celcuity a “differentiated foothold” in a setting where competition has largely centered around patients with PIK3CA mutations.
Celcuity has also noted how Revtorpyk was associated with lower patient discontinuation rates due to treatment-related adverse events than what was observed in testing of other approved drug combinations for this patient population.
However, company shares fell by nearly 20% on Wednesday following the news and a subsequent conference call with analysts. The drug’s expected launch timing surprised investors given “prior commentary on launch readiness,” wrote Leerink Partners analyst Andrew Berens. Revtorpyk’s prescribing information also included “higher discontinuation rates than expected,” as the numbers were different than what the company disclosed at a medical meeting last year. In speaking with experts, Berens noted how real-world experience will be “crucial to shaping clinician and patient perception” of Revtorpyk.
Still, others rallied to Celcuity’s defense. In an email to BioPharma Dive Wednesday, Citizens JMP Securities analyst Silvan Turkcan said there was nothing in the drug label that raised concern. He argued, too, that, Revtorpyk represents a meaningful improvement in the second-line setting for people with ER-positive, HER2-negative tumors.
Raycroft, meanwhile, wrote that Celcuity’s “strong” data, “manageable” safety compared to other approved treatments and more recent success in patients with PIK3CA mutations support a “credible path” to a broader sales opportunity. The company plans to submit a supplemental application in the third quarter to expand use.
Celcuity hasn’t yet revealed Revtorpyk’s cost, but said it will price the treatment at a premium compared to current therapies.
