Perspective Therapeutics pairs PSV359 with Merck's Keytruda and gains FDA Fast Track status

Perspective Therapeutics has secured access to Merck's best-selling checkpoint inhibitor for a possible combination with its lead sarcoma candidate, while the US regulator has given that candidate faster-track status. The company disclosed both developments on 9 November 2026 with its third-quarter results.

Under the Merck arrangement, which covers drug supply and joint work, Perspective will explore using PSV359 together with pembrolizumab, marketed as Keytruda. No financial terms were disclosed, and nor was the design of any trial, so the commercial value of the deal cannot be judged from the information released. Any combination study would have to establish the safety and dosing of the two agents together.

The FDA granted Fast Track status to PSV359 for solitary fibrous tumours that are positive for fibroblast activation protein (FAP). The programme is meant to speed development and review of treatments for serious conditions with unmet need, and it gives sponsors more frequent contact with the agency.

Elsewhere in the pipeline, bamzireotide navoxetan, aimed at neuroendocrine tumours, received European orphan designation in July 2026. Perspective is targeting an end-of-Phase 2 meeting with the FDA in the first quarter of 2027.

The company reported a third-quarter net loss of $32.4 million and about $202 million in cash. It expects that cash to fund operations into 2028, a guidance figure that rests on its own planning assumptions.