Clinical Hold on Mersana Trial After Patient Death

FDA has placed a clinical hold on a Mersana Therapeutics Phase 1 study of XMT-1522 after the company reported a Grade 5 Serious Adverse Event (patient death) in dose level seven of the therapy. “While the partial clinical hold remains in effect, no new patients will be enrolled in the study, though current study participants in its ongoing dose levels will continue to receive drug and otherwise participate in the trial consistent with its protocol,” the company says. “Based on the totality of the data we have for XMT-1522, we believe that it continues to be a promising drug candidate in the solid tumor setting and we will be initiating the proper steps with the objective of resuming enrollment,” it says. The Phase 1 protocol is evaluating XMT-1522 in patients with advanced HER2-positive breast and gastric cancer, as well as advanced breast cancer with low HER2 expression and non-small cell lung cancer.