08:05 AM EDT, 06/18/2025 (MT Newswires) -- Scholar Rock ( SRRK ) said Wednesday that a phase 2 trial showed that apitegromab combined with tirzepatide achieved a 54.9% preservation of lean mass compared with tirzepatide alone, leading to higher quality weight loss.

The trial demonstrated that 30% of total weight loss with tirzepatide alone was due to lean mass loss, which can cause health risks, the company said. Apitegromab supports healthier weight loss by preserving lean mass, according to Scholar Rock ( SRRK ) President of R&D Akshay Vaishnaw.

The combination of the two drugs was generally well tolerated, and apitegromab's safety profile was consistent with prior clinical studies, Scholar Rock ( SRRK ) said.

Scholar Rock ( SRRK ) shares were up nearly 14% in recent premarket activity Wednesday.