Mesoblast's Cell Therapy for Graft-Versus-Host Disease Wins FDA Approval; Stock Soars 42%

Mesoblast's Cell Therapy for Graft-Versus-Host Disease Wins FDA Approval; Stock Soars 42%

The FDA has approved Mesoblast Limited's (NASDAQ: MESO) Ryoncil (remestemcel-L), marking it as the first mesenchymal stromal cell (MSC) therapy in the U.S. and the sole treatment for steroid-refractory acute graft-versus-host disease (SR-aGvHD) in children as young as two months old.

Stock Impact:

Following the announcement, Mesoblast's stock surged 42.6%, reaching $17.47 in premarket trading on Thursday, signaling strong market confidence in the breakthrough therapy.

Significance of Approval:

Ryoncil offers a vital solution for SR-aGvHD, a severe complication affecting approximately 50% of the 10,000 annual U.S. bone marrow transplant patients. Nearly half of these cases fail to respond to steroids, the standard first-line treatment.

Trial Results:

In a Phase 3 trial, 70% of children with severe SR-aGvHD achieved a response by Day 28, a key indicator of survival. Of these, 30% showed complete recovery, and 41% experienced partial improvements. The treatment was well-tolerated, with 85% of participants completing the full course without interruptions.

Mesoblast’s Ryoncil approval addresses a critical unmet need, offering hope to patients and reinforcing the potential of MSC-based therapies in regenerative medicine.