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# Uncertainty for Gene Therapy, Rare Disease & Vaccines in Prasad Exit Wake
- URL: https://www.fdaweb.com/uncertainty-for-gene-therapy-rare-disease-vaccines-in-prasad-exit-wake/
- Published: 2026-03-13T12:00:00.000Z
- Updated: 2026-09-14T13:35:29.000Z
- Author: David McFarland
- Tags: Biologics, #legacy-id-D5160815

CBER director **Vinay Prasad**’s departure at the end of next month is raising questions across the biotechnology sector about how the agency’s approach to vaccines, gene therapies and rare-disease treatments could change in the months ahead. Prasad has had a tumultuous tenure that lasted less than a year but included a series of high-profile regulatory clashes with drugmakers and patient groups and internal staff.

Prasad, an academic oncologist who joined the agency 5/2025, quickly became one of the most polarizing figures there. His tenure was marked by disputes over drug approvals, vaccine policy and rare disease therapies, as well as internal leadership changes at the center. Before joining the agency, he was known as a vocal critic of weak clinical evidence supporting some drugs and vaccines. Once at FDA, he sought to impose stricter evidentiary standards in certain areas, including gene therapies and treatments for rare diseases.

Those efforts drew criticism from patient advocates and some industry groups who said the agency was becoming unpredictable and less flexible for companies developing treatments for small patient populations. At the same time, Prasad helped shape some of the administration’s broader regulatory initiatives, including programs intended to accelerate the review of certain high-priority medicines.

Several disputes with pharmaceutical companies amplified tensions during his tenure. Most recently, CBER has been engaged in a public dispute with uniQure over its experimental gene therapy for Huntington’s disease. Regulators asked the company to conduct an additional study to support approval, a request uniQure and some patient advocates argued would take too long and place additional burdens on patients with the rare neurological condition.

The uniQure dispute culminated last week in an anonymous FDA official bashing the company and the product’s clinical data during a media update with reporters. The official was later identified as Prasad, whose departure from the agency was announced the following day. The episode has also drawn attention because the anonymity request with media occurred within an administration that has repeatedly pledged “radical transparency,” according to a *Biospace* [editorial](https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://www.biospace.com/fda/prasads-request-to-remain-anonymous-shines-light-on-fdas-transparency-problem&ved=2ahUKEwjZrOTdvJ2TAxWjGVkFHf7cMRsQFnoECBwQAQ&usg=AOvVaw10TNxvsU8OVdLZb-7Iq73r).

Another incident involved his overruling staff to issue a "refusal-to-file" letter for a Moderna influenza vaccine, which was later reversed. Prasad also faced internal and external scrutiny for an internal memo in which he claimed Covid vaccines were responsible for the deaths of at least 10 children, a claim that critics said relied on unverified and “incomplete information.”

Additionally, Prasad has faced internal complaints that alleged he fostered a "toxic" work environment, which included allegations of verbally berating staff and retaliating against employees who disagreed with his decisions. These incidents have been investigated by outside firm Professional EEO Services. Media reports indicated that career staff felt intimidated, with some attempting to transfer out of the vaccine center. In a memo to staff, Prasad reportedly demanded that employees who disagreed with him should resign, calling internal disputes "unethical" and "illegal".

The controversies contributed to investor volatility in the sector, with some biotech stocks rising sharply after news of Prasad’s upcoming exit. Analysts say Prasad’s departure could mark a turning point for the FDA’s approach to regulating biologic products. Some investors believe his exit could lead to a more predictable or industry-friendly regulatory environment, particularly for companies developing rare-disease therapies. One analyst note described the leadership change as potentially a “big win for biotech,” especially for firms focused on treatments for small patient populations.

Others caution that the impact will depend heavily on who replaces him. The next CBER director could either continue Prasad’s emphasis on stricter scientific standards or shift toward a more flexible regulatory posture in line with broader administration priorities around faster access to treatments.

Prasad’s exit also comes amid a period of unusual turnover within FDA. The biologics chief had already briefly left the agency once in 2025 before returning weeks later at the request of FDA leadership. His tenure followed the departure of longtime CBER director **Peter Marks**, who had overseen the rapid expansion of gene and cell therapies during the previous decade. There has also been equally choppy leadership stability at CDER. Observers say the rapid succession of leadership changes could affect regulatory consistency at a time when the biologics pipeline — including gene editing, mRNA vaccines and personalized cell therapies—is expanding rapidly.

With Prasad set to return to academia at University of California San Francisco, attention is now shifting to who will lead CBER and how that leader will shape regulatory policy. Biotechnology companies will be watching closely for signals on several issues, including evidentiary standards for rare disease therapies, oversight of gene therapy trials and the FDA’s evolving approach to vaccines.

For an industry already navigating scientific risk, high development costs and shifting political priorities, the direction taken by the next biologics chief could play a significant role in determining how quickly new therapies reach the market — and how much evidence regulators require before approving them.