United President, Donald Trump, has discontinued a $258 million HIV vaccine research programme, effectively shutting down two major research hubs that have been instrumental in the decades-long search for a vaccine against the virus.

Officials from the HIV division of the National Institutes of Health (NIH) delivered the news to programme leaders on Friday. The NIH indicated that the move followed an internal review and was based on a decision to focus on existing strategies for eliminating HIV, rather than continuing to fund vaccine research efforts.

The affected teams, including Duke University’s Human Vaccine Institute and the Scripps Research Institute in California, had been collaborating with a wide network of research partners on work that extended beyond HIV, including the development of COVID-19 treatments, snake anti-venom, and therapies for autoimmune diseases. The programme’s termination halts ongoing experiments and disperses research teams that have taken years to assemble.

The development is the latest in a series of cuts to HIV-related initiatives under the Trump administration. In addition to ending the vaccine programme, the NIH has paused funding for a clinical trial of an HIV vaccine developed by Moderna. Separately, funding for state and territorial HIV prevention efforts has also been withheld, causing disruptions in several jurisdictions, including Texas.

This latest decision is expected to significantly delay progress in HIV vaccine development, with experts warning that dismantled programmes and disbanded teams will be difficult to rebuild in the future.