FDA places partial clinical hold on umbralisib and ublituximab trials in CLL and NHL

The U.S. Food and Drug Administration (FDA) has placed a partial clinical hold on a series of trials investigating the use using umbralisib in combination with ublituximab (U2) as a treatment for chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphoma.¹ No new patients will be able to sign up for these trials; although, those already enrolled and experiencing a benefit will be able to continue with consent. Notably, the hold is not based on new data, but on concerns that will be presented later in March/April 2022.

On March 29, 2021, a biologics license application was submitted to the U.S. FDA for U2 based on results from the phase III UNITY-CLL trial (NCT02612311), which showed a progression-free survival benefit of U2 compared with obinutuzumab plus chlorambucil for patients with treatment-naïve and relapsed/refractory CLL. The U2 combination has also previously been granted fast track designation and orphan drug designation by the FDA for the CLL indication.

About U2

The U2 combination regimen comprises the investigational, anti-CD20 monoclonal antibody, ublituximab, and the investigational, once-daily, oral inhibitor of PI3K-delta and CK1-epsilon, umbralisib.