CHICAGO (TheStreet) -- An experimental, targeted immunotherapy developed by Celldex Therapeutics (CLDX) continues to delay tumor growth and extend survival in patients with a certain type of recurrent brain tumor, according to an update of a clinical trial disclosed Sunday.
The clinical benefit of the Celldex therapy, known as Rintega, narrowed somewhat compared to results from the phase II study first disclosed last fall but remain statistically significant.
Rintega combined with Roche's Avastin reduced the risk of death in a genetic subtype of recurrent brain tumor patients by 43% compared to Avastin plus a control agent, according to the study update reported Sunday at the American Society of Clinical Oncology (ASCO) annual meeting. Last November, an earlier analysis of the same study showed Rintega tied to a 53% reduction in the risk of death.
Celldex is meeting with regulators at the U.S. Food and Drug Administration to determine if the Rintega data from the recurrent brain tumor study known as ReACT are strong enough to file for accelerated approval.
Celldex CEO Anthony Marucci said more definitive regulatory plans for Rintega will be announced once those FDA talks are complete.
One of the issues being worked out is how to package the Rintega data for an accelerated approval filing in recurrent brain tumors based on a study with a primary endpoint -- progression-free survival at six months -- not typically used by regulators, said Celldex Chief Medical Officer Tom Davis. Further complicating the regulatory discussions -- in a good way -- is the survival benefit from Rintega observed in the study. The FDA has also already anointed Rintega as a Breakthrough Therapy for the treatment of brain tumors.