PRV Watch

I have a bad track record of hot takes... so here's another. 🔥Hot take: $PRME Prime Medicine should not be eligible for a Priority Review Voucher if they get approval for PM359 in Chronic Granulomatous Disease (CGD). Prime plans to file a BLA for PM359, an ex vivo prime-edited autologous stem cell therapy for CGD. Prime discontinued this program last year due to the commercialization cost and limited opportunity in this indication. Now it's back after several regulatory tailwinds: • FDA reduced requirement from 2 pivotal trials to 1 • CMC expectations eased for cell & gene therapies • New plausible mechanism pathway supporting accelerated approval Prime will be seeking approval following positive proof-of-concept data from two patients treated in its Phase 1/2 study. Those patients were 18 and 57 years old. Eligibility for a Rare Pediatric Disease Priority Review Voucher requires a meaningful pediatric study. From FDA’s 2019 Draft Guidance: "...to be eligible for a voucher, the approved product: • should have been studied in a clinically meaningful pediatric population with the rare disease (although the studies may also include adults in appropriate circumstances), and • the pediatric data should have been critical to obtaining adequate labeling for the pediatric population in terms of safety, effectiveness, and dosage information (although data from studies including adults may also have supported the pediatric labeling in appropriate circumstances)...." Hard to see how that standard is met with two adult patients. That said, these are very different times at the FDA, and issuing a PRV here could meaningfully incentivize R&D in pediatric rare diseases with extremely small patient populations.

NEW FDA vaccines chief Vinay Prasad will leave the agency at the end of April Gift link below