The Bruton tyrosine kinase inhibitor is already approved for the treatment of adults with mantle cell lymphoma who have received at least one prior therapy, and multiple trials are underway to evaluate the drug’s use in a variety of B-cell malignancies, according to the drug’s sponsor, AstraZeneca.
The current designation was based on preliminary results from two phase 3 trials – ELEVATE-TN and ASCEND. In the three-arm ELEVATE-TN trial, researchers evaluated acalabrutinib alone or in combination with obinutuzumab versus chlorambucil plus obinutuzumab in previously untreated patients with CLL. In the two-arm ASCEND trial, previously treated patients with CLL were randomized to receive acalabrutinib monotherapy or the physician’s choice of either rituximab plus idelalisib or rituximab plus bendamustine.
Interim analyses of the two trials showed that acalabrutinib alone, or in combination, significantly improved progression-free survival without raising safety concerns.
Breakthrough therapy designation allows for an expedited review by the FDA for treatments aimed at treating serious conditions where there is preliminary clinical evidence showing a substantial improvement over an available therapy or a clinically significant endpoint.