Photo by Linda Bartlett
The US Food and Drug Administration (FDA) has granted priority review for an application for ofatumumab (Arzerra) as maintenance therapy in
patients with relapsed chronic lymphocytic leukemia (CLL).
The FDA grants priority review to investigational therapies that, if approved, may offer significant improvements in the treatment, prevention, or diagnosis of a serious condition.
The designation shortens the review period from 10 months to 6 months.
Ofatumumab is a human monoclonal antibody (mAb) designed to target CD20 on the surface of CLL cells and normal B lymphocytes.
The mAb is already FDA-approved to treat patients with CLL that is refractory to fludarabine and alemtuzumab. Ofatumumab is also approved for use in combination with chlorambucil to treat previously untreated patients with CLL for whom fludarabine-based therapy is considered inappropriate.
The FDA said it aims to complete its review of the application for ofatumumab as maintenance therapy in relapsed CLL by January 21, 2016.
PROLONG trial
The application for ofatumumab as maintenance is based on interim results from the phase 3 PROLONG (OMB112517) trial, which were presented at ASH 2014.
In this trial, researchers compared ofatumumab maintenance to no further treatment in patients with a complete or partial response after second-
or third-line treatment for CLL.
Interim results suggested that ofatumumab significantly improves progression-free survival but not overall survival.
The median progression-free survival was about 29 months in patients who received ofatumumab and about 15 months for patients who did not receive
maintenance (P<0.0001).
There was no significant difference in the median overall survival, which was not reached in either treatment arm.
Ofatumumab development
Ofatumumab is approved in more than 50 countries worldwide as monotherapy for CLL patients who are refractory to fludarabine and alemtuzumab.
In the European Union, ofatumumab is approved for use in combination with chlorambucil or bendamustine to treat CLL patients who have not received prior therapy and who are not eligible for fludarabine-based therapy.
Ofatumumab is not approved anywhere in the world as maintenance therapy for relapsed CLL. The drug is being developed by Genmab and Novartis.
