Mesoblast Gets FDA Approval for New Ryoncil Potency Assay

07:32 AM EDT, 09/24/2026 (MT Newswires) -- Mesoblast (MESO) said Thursday that the US Food and Drug Administration approved a new potency assay, T-cell Proliferation Inhibition BioAssay, for release and stability monitoring of all new commercial Ryoncil lots. The assay will be used alongside existing potency tests to detect potential shifts in product potency resulting from manufacturing process changes or production at new facilities, the company said. Mesoblast said the assays are intended to ensure Ryoncil remains consistent and potent and meets the requirements of its biologics license, it added. Mesoblast shares were up 5.9% in premarket activity.