FDA panel says Vertex/CRISPR to assess safety risks of gene therapy in follow-up study

Crispr Therapeutics AG

31/10/2023 22:26

Oct 31 (Reuters) - A panel of advisers to the U.S.
health regulator said on Tuesday Vertex Pharmaceuticals  VRTX.O 
and CRISPR Therapeutics  CRSP.BN  could assess potential safety
risks of their sickle cell disease gene therapy after approval.
    If the therapy is approved, Vertex has proposed a 15-year
follow up of patients to evaluate the safety outcomes of the
therapy. 
    The inherited red-blood-cell disorder causes the cells to
become sickle-shaped due to abnormal levels of hemoglobin in the
body. A vaso-occlusive crisis occurs when sickled red blood
cells block blood flow to the point that tissues become deprived
of oxygen and causes pain.
    The panel members said the 15-year follow up will help
generate data from real-time monitoring of the therapy, which
uses the new gene editing CRISPR technology.
    Staff reviewers to the U.S. Food and Drug Administration
said the new type of technology raised concerns about the "off
target", or unintended genomic alterations that can potentially
cause other side effects, but did not raise any concerns about
the therapy's efficacy.
    The therapy, exagamglogene autotemcel or exa-cel, met the
main goal of a late-stage study. Patients who were treated with
the therapy were free from severe vaso-occlusive crisis for 12
months from the infusion of exa-cel.
   "With regards to off target analysis we want to be careful to
not let the perfect be the enemy of the good," said Dr. Scot
Wolfe, professor at the department of molecular, cell and cancer
biology at UMass Chan Medical School.
    Analysts have been optimistic the therapy, which is a
first-of-its-kind product to reach the FDA for review, will win
the health regulator's nod by Dec. 8.
    "It was made pretty clear that any theoretical off-target
editing concerns do not outweigh the benefits of drug approval,"
said Salim Syed, analyst at Mizuho.
    

 (Reporting by Sriparna Roy in Bengaluru; Editing by Krishna
Chandra Eluri)
 ((Sriparna.Roy@thomsonreuters.com;))