The National Institutes of Health plans to close the door on one of the few pathways available to international students on visas to forge a career in biomedical research in the United States.

The agency intends to limit eligibility for its “Pathways to Independence” award to U.S. citizens, permanent residents, and non-citizen nationals, according to an internal presentation viewed by STAT. Historically, it has been one of few programs to offer funding to international scientists on a visa. Without it, experts fear, even the most promising scholars will struggle to find footing to establish themselves in the U.S.

The pathway, referred to as a K99/R00, includes funding for two years of a researcher’s postdoctoral studies, and three years of funding as an independent lab head.