The U.S. Food and Drug Administration (FDA) granted breakthrough therapy designation to BeiGene’s zanubrutinib as a treatment candidate for adults with mantle cell lymphoma (MCL) who have received at least one prior treatment.
Breakthrough therapy designation is intended to accelerate the development and review of a potential therapy for a serious or life-threatening disease, with clinical evidence of substantial improvement over existing options. The program’s features include more intensive FDA guidance throughout treatment development — such as ensuring efficient design of clinical trials — and eligibility for priority review.
“We are very excited to receive the Breakthrough Therapy designation from the FDA,” Jane Huang, MD, BeiGene’s chief medical officer, hematology, said in a press release. Huang said the Beijing-based company believes that this designation from the FDA “underscores the potential of zanubrutinib as a meaningful treatment for patients with MCL who have received at least one prior therapy.”
Zanubrutinib is a small molecule inhibitor of Bruton’s tyrosine kinase (BTK). This enzyme is part of a pathway that helps immune B-cells stay alive and divide. Zanubrutinib’s targeting of BTK blocks survival signals in tumor B-cells, leading to their death and halting lymphoma’s progression. Huang said the therapy “has been designed to maximize BTK occupancy and minimize off-target effects.”
Besides MCL, a form of non-Hodgkin’s lymphoma, zanubrutinib is being tested in a Phase 3 trial (NCT03734016) in refractory or relapsed patients with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL). The study, which is enrolling participants, is comparing zanubrutinib to Imbruvica (ibrutinib), also a BTK inhibitor.
Other Phase 3 studies that are part of the medicine’s broad program include a global trial (NCT03053440) for people with Waldenström macroglobulinemia, also comparing zanubrutinib to Imbruvica, and another global study (NCT03336333, also enrolling patients) for previously untreated CLL/SLL patients.
BeiGene is also conducting an open-label Phase 2 study (NCT03520920) in China for patients with relapsed or refractory follicular lymphoma. Two pivotal Phase 2 trials of zanubrutinib in patients with MCL (NCT03206970) and CLL/SLL (NCT03206918) have been completed in China.
Preliminary Phase 1 data presented in September 2018 revealed that zanubrutinib was well-tolerated and had a high rate of activity in several B-cell lymphoma subtypes. Among the two MCL patients included in the study, one had complete response to zanubrutinib and the other had stable disease.
Overall, “more than 1,300 patients worldwide have been treated with zanubrutinib,” Huang said.
Zanubrutinib has received fast track designation from the FDA for patients with Waldenström macroglobulinemia and is being reviewed in China as a potential treatment for previously treated patients with either MCL or CLL/SLL.