The Mesoblast Limited (ASX: MSB) share price has taken a dive today after the company’s quest to obtain FDA approval for its lead drug candidate hit a speed bump.
Today’s fall comes in the lead up to Mesoblast’s meeting with the Oncologic Drugs Advisory Committee (ODAC) on Thursday. ODAC is an independent panel of experts that provides advice and appropriate recommendations to the US Food and Drug Administration (FDA).
The meeting will review evidence of the effectiveness of Mesoblast’s flagship drug product (DP), remestemcel-L, as a treatment for paediatric patients with steroid-refractory acute graft versus host disease (SR-a-GVHD).
Graft versus host disease is a potentially life-threatening condition that develops when a donor transplant’s immune cells (the graft) attack the recipient’s healthy cells (the host).
Remestemcel-L is currently available for the treatment of SR-a-GVHD in children in Japan, but the company is awaiting approval from the FDA in order to commercialise the drug in the US market.
However, hopes of FDA approval took a hit today after the FDA released a briefing document ahead of the meeting on Thursday.
What did the FDA say?
According to the briefing document, the FDA has concerns over Mesoblast’s license application:
“FDA’s position is that the product attributes the Applicant has identified as related to potency and activity, however, do not have a demonstrated relationship to the clinical performance of specific DP lots, and that the product’s proposed immunomodulatory mechanism of action has not been demonstrated in vivo in study subjects receiving remestemcel-L.”
“Without a demonstrated relationship with clinical effectiveness and/or in vivo potency/activity, controlling these CQAs [critical quality attributes] may not be sufficient to ensure the manufacturing process consistently produces remestemcel-L lots of acceptable quality,” the FDA added.
The meeting is scheduled for Thursday, August 13 and will be conducted throughout the course of the day. The morning session will discuss issues related to the characterisation and CQAs of remestemcel-L (mentioned above), while the afternoon session will discuss the Phase 3 trial results and supporting clinical data.
ODAC will vote in the afternoon session on whether the available data supports the efficacy of remestemcel-L in paediatric patients with SR-a-GVHD.
In an ASX release this afternoon, Mesoblast made sure to note that “although the FDA will consider the recommendation of the advisory committee, the final decision regarding the approval of the product is made by the FDA solely, and the recommendations by the panel are non-binding.”
The company will likely make an announcement regarding the panel’s decision on Friday. In the meantime, be sure to check out our ASX reporting season page for daily updates.