NIH Suspends 40 Pathogen Studies Under Trump Gain-of-Function Order, Leaving Researchers in the Dark

The National Institutes of Health has suspended at least 40 pathogen research grants it identified as potentially constituting dangerous gain-of-function work, acting under a May 2025 executive order from President Trump. The agency reviewed more than 71,000 funded projects to produce that list, and suspension notices went out in waves starting in late June. That's the factual core. What the record also shows is that the criteria used to select those 40 projects are contested, the appeals process doesn't exist, and NIH's own staff don't know what the rules will be once a permanent policy arrives.

According to an exclusive report in Science, NIH Deputy Director Matthew Memoli described the agency's posture in a July 3 draft letter to the White House: "NIH has identified 40 projects that may meet the definition of dangerous gain-of-function research. ... Erring on the side of caution, all projects potentially meeting the definition are being suspended." That word "potentially" is doing real work. For 17 of those 40 projects, the rationale column in the NIH spreadsheet reads "suspended out of an abundance of caution", not a determination of risk, but a hedge.

The scope of what got swept in is a legitimate concern. Science's reporting identifies suspended studies covering tuberculosis bacteria, COVID-19, influenza, dengue, Zika, and a project to modify a flu virus to treat cancer. One suspended project studied protective antibodies to two deadly viruses without using the actual pathogens. Richard Chaisson, a tuberculosis researcher at Johns Hopkins, told Science one of the paused Mtb projects studied a loss of function, not a gain. Stanford microbiologist David Relman, who has pushed for stronger gain-of-function oversight for years, reviewed the NIH list and said it was difficult to determine why many of those projects were selected.

The dual-use ambiguity here is real and worth naming directly. Gain-of-function experiments sit at the center of a long-running biosecurity debate because the same techniques that help scientists understand how pathogens evolve could, in the wrong hands or with deliberate design, make a pathogen more dangerous. Executive Order 14292 targets what it defines as "dangerous" gain-of-function research, but as Science notes, the executive order's definition was considered so broad by many infectious disease scientists that it could cover relatively low-risk work. NIH provided some guidance after the order, but the new permanent policy is still being written, by the White House, not NIH, according to NIH Director Jayanta Bhattacharya.

That governance gap is creating operational paralysis. Volker Briken, who studies Mycobacterium tuberculosis at the University of Maryland, told Science he received his suspension letter on June 27 "completely out of the blue," responded within two days as instructed, and then heard nothing back, including missing a June 1 funding installment. The American Society for Microbiology called on NIH to be more transparent and said, in a statement obtained by Science, that "this is all compounded by the lack of an appeals process."

The leadership picture at NIH's infectious disease institute compounds the uncertainty. Nature reported in May that eight of the top ten officials at NIAID have been pushed out since Trump took office. A separate Science investigation found that NIAID's acting director John Beigel was replaced in December 2025 after a clash over a seasonal flu grant that his division hadn't flagged during the summer review. That grant, held by University of Illinois Urbana-Champaign virologist Christopher Brooke, was for a five-year, $2.5 million study of how surface proteins on seasonal influenza strains evolve under immune pressure. NIH deemed it potentially able to produce viruses capable of escaping immunity, work that HHS had not historically classified as posing pandemic potential. Brooke told Science he was told by NIH staff there'd be "no discussion about redesign or rescoping of experiments."

According to a CSIS analysis published in May 2026, the FY2026 budget proposal already threatened cuts to NIH of $18 billion and to the Administration for Strategic Preparedness and Response of $240 million, and the White House Office of Pandemic Preparedness had already lost its top official. The suspension wave lands on top of that institutional thinning.

Assessment confidence on the following is low-to-moderate: whether the 40-project list accurately captures the actual risk profile the executive order was designed to address. The policy definition remains unfinalized, the selection rationale is not publicly documented in detail, and affected researchers have no formal recourse. That's not a biosecurity posture; it's an interim state that leaves both the research enterprise and the oversight architecture in limbo.

Sources cited:
- Science / AAAS, Exclusive: NIH suspends dozens of pathogen studies over 'gain-of-function' concerns (https://www.science.org/content/article/exclusive-nih-suspends-dozens-pathogen-studies-over-gain-function-concerns)
- NIH Notice NOT-OD-25-127, Implementation Update: Terminating or Suspending Dangerous Gain-of-Function Research (https://grants.nih.gov/grants/guide/notice-files/NOT-OD-25-127.html)
- Science / AAAS, NIH official resigns after flap over risks of seasonal flu virus study (https://www.science.org/content/article/nih-official-resigns-after-flap-over-risks-seasonal-flu-virus-study)
- Nature, Exclusive: NIH ousts infectious-disease leaders as COVID scientists face US charges (https://www.nature.com/articles/d41586-026-01558-w)
- CSIS, Opportunities to Strengthen U.S. Biosecurity from AI-Enabled Bioterrorism: What Policymakers Should Know (https://www.csis.org/analysis/opportunities-strengthen-us-biosecurity-ai-enabled-bioterrorism-what-policymakers-should)