Merck announced that it is pausing enrollment onto 2 phase 3 trials of pembrolizumab (Keytruda®) in combination with other agents to treat multiple myeloma (MM).
An external Data Monitoring Committee recommended the trial be interrupted “to allow for additional information be collected to better understand more reports of death” in the pembrolizumab groups in the KEYNOTE-183 and KEYNOTE-185 trials.
Patients currently enrolled on the trials can continue to receive treatment. Other pembrolizumab trials are continuing without changes.
Merck in its statement did not disclose the number of deaths nor provide any other details on the deaths.
Pembrolizumab is a humanized monoclonal antibody that blocks interaction between the programmed cell death protein 1 (PD-1) and its receptor ligands, PD-L1 and PD-L2.
The US Food & Drug Administration approved pembrolizumab to treat unresectable or metastatic melanoma after ipilimumab treatment.
Pembrolizumab has also been approved to treat non-small cell lung cancer, head and neck squamous cell cancer, classical Hodgkin lymphoma, urothelial carcinoma, and microsatellite instability-high solid tumors.
KEYNOTE-183 (NCT02576977), which has an estimated enrollment of 300 patients, is comparing the combination of pembrolizumab, pomalidomide, and low-dose dexamethasone to pomalidomide and low-dose dexamethasone alone in patients with relapsed or refractory MM who have undergone at least 2 lines of prior therapy.
KEYNOTE-185 (NCT02579863), which has an estimated enrollment of 640 patients, is comparing the combination of pembrolizumab, lenalidomide, and low-dose dexamethasone to lenalidomide and low-dose desamethasone alone in patients with newly diagnosed and treatment-native MM who are ineligible for autologous stem cell transplant.
The comparator agents pomalidomide (Pomalyst®) and lenalidomide (Revlimid®) are products of Celgene Corporation.