Upon the announcement of the acceptance of Mesoblast Limited's (NASDAQ: MESO) licensing application by regulatory authorities, the company's shares have witnessed a significant rise on the US stock charts. The price of MESO shares increased by 9.27% to $8.25 as of the most recent check made during the current trading session.

FDA Approves Mesoblast's Application

Mesoblast (MESO) said that their Biologics License Application (BLA) for resubmission has been accepted by the US Food and Drug Administration (FDA). Regarding Ryoncil, this BLA is intended for the treatment of pediatric patients with steroid-refractory acute graft versus host disease (SR-aGVHD).

The company's top product candidate, Ryoncil, is an experimental treatment consisting of culture-expanded mesenchymal stromal cells taken from an unrelated donor's bone marrow and given intravenously over many infusions.

Immunomodulatory characteristics of ryoncil work against the inflammatory pathways linked to SR-aGVHD. This is accomplished by preventing effector T cell activation and proliferation, reducing pro-inflammatory cytokine production, and promoting the migration of anti-inflammatory cells to impacted tissues.

Designations for Priority and Fast Track Reviews

Remetemcel-L, the active component of Ryoncil, has been given Fast Track status by the FDA, which will speed up the research and evaluation of treatments for severe illnesses with unmet medical needs.

It has also been granted the Priority Review classification, which is given to medications that treat critical illnesses and provide considerable increases in either safety or efficacy above currently available therapies.

The FDA's approval of the resubmission is regarded as a full response, and Mesoblast hopes to hear back from the agency by January 7, 2025, the Prescription Drug User Fee Act's (PDUFA) deadline.

In its resubmission on July 8, 2024, Mesoblast addressed the remaining Chemistry, Manufacturing, and Controls (CMC) issues in response to FDA input in March 2024 that said the clinical results from the Phase 3 trial MSB-GVHD001 looked good enough to warrant the BLA submission.

Moreover, no Form 483 was issued as a consequence of the FDA's Pre-License Inspection (PLI) of the remestemcel-L manufacturing process in May 2023.

Implications for Ryoncil Approval

The FDA's acceptance of the BLA resubmission for review marks a critical step towards the potential approval of Ryoncil for treating children with SR-aGVHD, signifying a significant milestone for Mesoblast Limited.