The biologics center director reportedly became personally involved after the team reviewing the rare blood disorder filing asked for an extension to the CNPV-accelerated timeline.
Disc Medicine has been rocked by a report that FDA biologics center director Vinay Prasad is skeptical of the efficacy of bitopertin, a candidate under the agency’s review to treat the rare blood disorder porphyria.
As part of a broader story on the Commissioner’s National Priority Voucher (CNPV), STAT reported that Prasad has become personally involved in the FDA’s review of Disc’s bitopertin. Prasad reportedly intervened after the FDA team handling Disc’s approval application asked for more time to review the filing, which should be assessed in one to two months under the terms of the CNPV scheme.
Prasad reportedly expressed skepticism about the drug’s efficacy in porphyria. The report sent Disc shares down as much as 21.7% Friday, although the stock recovered somewhat to close down 11.5% at $80.04.
Disc executives held a call with analysts to discuss the situation Friday. Truist Securities analysts said in a note to investors that Disc management was “blindsided” by the STAT report. The analysts titled the note “Hide Your Kids, Hide Your Wife, No One’s Safe From this FDA” and outlined the unprecedented nature of Prasad’s potential influence over the review.
“We are in uncharted territory,” Truist analysts said. “While we think Prasad’s personal involvement in any review naturally warrants some caution, the information available today is far too limited to draw a definitive conclusion on the potential outcome.”
Analysts at Truist and BMO Capital Markets came away from the call with unanswered questions because Disc executives were unable to provide clarity. Disc’s team has no direct interaction with Prasad, Truist analysts said, but executives understand that he participates in “tumor board”-style CNPV reviews. His role, views and influence are unknown. As a small molecule, bitopertin is outside of Prasad’s remit as biologics head.
Citing Disc executives, BMO analysts said the FDA has not communicated any efficacy concerns to the biotech, and no advisory committee has been noted as necessary. The FDA has raised procedural efficacy questions to clarify details such as a correlation between a biomarker and clinical benefit, BMO analysts said, but “the tone and tenor of interactions with FDA remains upbeat and collaborative.”
Truist analysts said Disc executives acknowledged there could be some validity to the report of potential timing constraints affecting the CNPV procedure. Disc’s regulatory team believes the agency has been operating under a compressed review timeline but was on track for the publicly communicated CNPV date, Truist analysts said.
BMO and Truist analysts voiced optimism that bitopertin will be approved, even if it misses the targeted authorization date. Truist said that the next steps if the decision is unfavorable are unclear, given how new the CNPV program is. They added that Disc executives believe the FDA would send a complete response letter.
