Amgen Inc. has stopped enrollment in two early-stage clinical trials for two separate multiple myeloma drugs as possible heart damage was identified in patients during one of the studies.
The Thousand Oaks, Calif.-based company put a clinical hold on a phase 1 study for a drug it has dubbed AMG 397 "to evaluate a safety signal for cardiac toxicity," according to a Sept. 12 release, indicating one or more patients have experienced heart problems.
Amgen also put a hold on a study for a similar drug called AMG 176, though the company did not indicate any safety signals there.
The company did not disclose the extent of the heart conditions and the number of patients who experienced them.
Both drugs belong to a class called MCL-1 inhibitors, which have shown in animal trials to be associated with sudden onset heart failure, according to a note from SVB Leerink analyst Geoffrey Porges.
"So far the number of cardiac events appears to be small, but so too is the total exposure to the drugs, which raises the significance of these observations," Porges said.
Judging from previous data on MCL-1 drugs, Porges said the trial halt is unexpected and that Leerink had once regarded the class of drugs "as one of the company's more promising emerging oncology development programs."
Amgen will present the data Sept. 14 at the International Myeloma Workshop in Boston.
