Affimed shares dropped 28 percent on Monday following a company announcement that early studies of AFM11 have been put on hold after three patients taking the experimental drug suffered serious adverse events, included one death. The studies were testing the drug in patients with types of non-Hodgkin lymphoma and acute lymphoblastic leukemia.
The company stated that is has notified global health authorities of its decision to put a hold on the studies, and says it will work with regulators, as well as safety monitoring committees and the studies’ clinical investigators, to review the events and determine next steps.
In a press release, Affimed confirmed that the clinical hold will not affect the ongoing development of the company’s NK cell engager programs, which are based on targeting the NK cell receptor CD16A, a different approach than used for AFM11, which targets T cells through CD3.
AFM11, a CD19/CD3-targeting T cell engager, is being studied in two Phase I trials for the treatment of patients with relapsed or refractory CD19 positive B-cell NHL and ALL. Affimed revealed that the serious adverse events were seen in patients enrolled in the highest dose cohorts of each study.
In total, 33 subjects have been administered AFM11 across the two trials.