▼ Summary
– Vinay Prasad, the FDA’s top vaccine regulator, overruled agency scientists to refuse reviewing Moderna’s mRNA flu vaccine.
– Career scientists and a top official objected, with a memo and a meeting arguing the review should proceed.
– Prasad’s rejection was not based on problems with Moderna’s mRNA vaccine itself.
– Instead, he objected to the licensed vaccine Moderna used for comparison in its large Phase 3 trial.
– The FDA had previously reviewed and found Moderna’s trial plans acceptable on multiple occasions.
A significant decision regarding a new flu vaccine was made by a single official, overriding the consensus of scientific experts within the agency. Reports indicate that Vinay Prasad, the Trump administration’s top vaccine regulator at the FDA, personally rejected Moderna’s application for its mRNA flu shot, despite career scientists at the agency being prepared to review it. This move has raised questions about the influence of political appointees on scientific review processes, especially concerning public health innovations.
According to detailed accounts, a team of experienced FDA scientists was ready to evaluate the vaccine candidate. David Kaslow, a senior career official responsible for vaccine reviews, even authored a formal memo objecting to Prasad’s rejection. This document reportedly provided a thorough justification for why the review should move forward, underscoring the professional disagreement within the agency. The situation escalated during a meeting in early January, where scientists directly confronted Prasad about his decision, arguing it was misguided.
The core of Prasad’s objection did not involve safety or efficacy concerns with Moderna’s experimental mRNA technology itself. Instead, his issue centered on the comparator vaccine Moderna used in its large Phase 3 clinical trial. The company’s study, which involved nearly 41,000 adults aged 50 and older, compared its new mRNA shot against an already licensed seasonal flu vaccine. The FDA had reviewed and approved Moderna’s trial design on multiple occasions before the final submission, raising no objections to the plan at that time.
Moderna has acknowledged that during consultations, FDA scientists did suggest a different comparator vaccine for participants aged 65 and older, a group typically eligible for a high-dose flu shot. However, the company emphasizes that the agency ultimately deemed their proposed study design “acceptable.” This context makes the subsequent unilateral rejection by the political appointee more contentious, highlighting a rift between ongoing scientific assessment and a sudden administrative decision.
(Source: Ars Technica)
