Relay's treatment shown to shrink vascular malformations in mid-stage trial

Relay Therapeutics

19/05/2026 11:00

By Sahil  Pandey

May 19 (Reuters) - Relay Therapeutics RLAY.O said on Tuesday a mid-stage trial showed its experimental treatment can shrink vascular malformations and improve symptoms in patients with rare vascular disorders.

Relay's zovegalisib reduced lesion size by at least 20% in about 60% of patients at 12 weeks.

Nearly all patients showed some reduction in lesion size and remained on treatment at the data cut-off, the company said.

Around 89% of doctors and 79% of patients reported improvement in symptoms such as pain and swelling at 12 weeks.

The treatment showed activity in patients previously treated with medicines such as alpelisib and sirolimus, Relay added.

"With a mutant-selective approach, zovegalisib is able to achieve clinical activity with a much better tolerability profile," Don Bergstrom, president of R&D, told Reuters.

No patients discontinued treatment due to side effects, and serious side effects were limited, according to the company.

Lower doses appeared suitable for long-term use, while a higher dose was not considered suitable for further development in this patient group, the company said.

"There have been no discontinuations on our study to date due to adverse events and currently all patients remain on therapy," Bergstrom said.

Relay said the results support a more targeted approach that could avoid side effects seen with older drugs in the same class.

The company is enrolling more patients at selected dose levels in the next stage of the study, it added.

Zovegalisib is also being developed for breast cancer and received U.S. "breakthrough therapy" status in February in combination with fulvestrant for certain patients with advanced disease.

Vascular anomalies are rare conditions where blood or lymph vessels grow abnormally, leading to pain, swelling and other complications.

 (Reporting by Sahil Pandey in Bengaluru; Editing by Shailesh Kuber)

 ((Sahil.Pandey@thomsonreuters.com;))