On January 19, 2016, the FDA approved the use of ofatumumab to treat patients with recurrent or progressive chronic lymphocytic leukemia (CLL) who are in complete or partial response following at least two prior treatment therapies.
This is the third time ofatumumab has received FDA approval for the treatment of patients with CLL. Ofatumumab was initially approved in 2009 for the treatment of patients with CLL who are refractory to fludarabine and alemtuzumab, and subsequently approved in April 2014 for use in combination with chlorambucil for previously untreated patients with CLL.
This approval is for the use of ofatumumab as a maintenance therapy. A maintenance therapy is an additional therapy that is administered to a patient after completion of an initial therapy in order to prolong the response achieved.
What is ofatumumab?
Ofatumumab is a human monoclonal antibody designed to target the CD20 molecules found on the surface of CLL cells and B-cell lymphocytes. CD20 molecules are found in over 90% of B-cell lymphomas. Ofatumumab is an immunotherapy that works by attaching itself to the CD20 molecule found on the surface of B-cells and directs the immune system to kill the cancerous B-cells.
Why was ofatumumab granted FDA approval?
Ofatumumab received this FDA approval based on the results from the PROLONG trial. In this phase III study, the use of ofatumumab as maintenance therapy was evaluated against no further treatment of patients who were in a complete or partial response after second or third line CLL treatment. The trial demonstrated an improvement in progression free survival for patients receiving ofatumumab maintenance of 29.4 months compared with 15.2 months for those on observation.
Were there any side effects?
Common side effects included infusion reactions, neutropenia, and upper respiratory tract infection. There were no unexpected, or new side effects observed for the patients receiving ofatumumab maintenance. The most common side effects seen were those previously described with ofatumumab infusions, including infusion reactions, low neutrophil counts, and infections.
How can you access ofatumumab now?
While all available trials for people with CLL at WCM have recently closed, our understanding of how best to use ofatumumab continues to increase. You can look to this space for further updates on CLL trials examining the use of ofatumumab.
A full list of trials open at WCM for patients with CLL is available on our Joint Clinical Trials website.