Following recent regulatory setbacks for Marqibo (vincristine sulfate liposomes injection), and after a careful evaluation, Enzon determined it will not support further development of the product.
In January 2005, the FDA provided an action letter stating that Marqibo is “not approvable” under the FDA’s accelerated approval regulations for relapsed aggressive non-Hodgkin’s lymphoma. The FDA’s response also stated that additional randomized controlled studies would need to be conducted prior to re-applying for approval.
After a strategic analysis of the FDA’s recommendation, as well as the required investment, development timeframe, and associated development risks, Enzon concluded that it would be in its best interest to redirect its investment to pursue other opportunities.
Enzon said that it expects to pay Inex $5 million for certain contractual obligations, including development expenses and milestone payments.