- The Food and Drug Administration has agreed to quickly review BioMarin's experimental gene therapy for hemophilia A and make an approval decision by Aug. 21, according to a Thursday announcement from the company.
- Supporting the approval application are interim data from an ongoing late-stage study as well as 3-year data from a Phase 1/2 trial that showed patients given BioMarin's therapy, known as valrox, experienced few — and often zero — bleeding episodes annually. The late-stage study also found the blood-clotting protein missing in hemophilia rose in valrox-treated patients to levels that should prevent them from having severe bleeding episodes for years to come.
- If approved, valrox would likely come with a price tag ranging between $1 million and $3 million, according to BioMarin leadership. Despite the cost, analysts expect valrox to resonate with doctors and payers, and therefore present a competitive challenge to companies with marketed hemophilia drugs as well as those developing their own experimental gene therapies.
Though analysts continue to debate the particulars of a valrox launch, they generally expect the therapy to take a significant chunk of the hemophilia market. Cantor Fitzgerald found through a survey that doctors seem quite willing to prescribe valrox within a few years of its launch. SVB Leerink also saw patient and prescriber enthusiasm in its own research.
"We believe the hemophilia market may be less 'sticky' and more poised for disruption by next generation agents than is generally assumed based on historical behavior," SVB Leerink analysts wrote in an investor note last February.
For BioMarin, a market open for disruption could translate to big sales. According to Jefferies, consensus estimates on Wall Street put valrox sales at $44 million this year, growing to $190 million in 2021 and more than $1.3 billion in 2025. Last May, Jefferies said valrox accounted for 16% the value it modeled for BioMarin's stock price.
On the other end, valrox could threaten leaders in the hemophilia drug space. Roche's blockbuster drug Hemlibra, which comes with convenient dosing and a high list price, looks particularly vulnerable. Survey data from Citi Research cited by BioMarin showed U.S. hematologists said they would switch close to 40% of their Hemlibra-treated patients to a gene therapy within three years of valrox's launch.