US FDA places Mersana's ADC trial on partial hold after patient death
The Grade 5 serious adverse effect (AE) reported by the company refers to a patient death. This AE occurred while a patient was on dose level 7 of the company’s XMT-1522 trial. Due to the nature of the death, the investigator has ruled it possibly drug-related.
This partial hold will mean no new patients will be enrolled in the study. However, current participants will continue with the trial consistent with trial protocol.
The clinical trial is still believed to be promising in solid tumor therapy. Mersana stated their interest in working with the FDA and investigators to resolve this clinical hold.
Mersana has been working with Novella, a CRO, on this clinical trial.
XMT-1522 clinical trial
XMT-1522 is an antibody drug conjugate (ADC) that is known to target HER2-expressing tumors. The drug affects a HER2 antibody which is conjugated by Mersana’s Dolaflexin platform. This platform is linked with a proprietary auristatin payload.
XMT-1522 is designed to improve potency while increasing tolerability and has the potential to extend HER2-targeted therapy. This trial evaluates patients with advanced HER2-positive breast and gastric cancer, as well as non-small cell lung cancer.
We spoke with Eva Jack, chief business officer, and David Spellman, the chief financial officer at Mersana Therapeutics, regarding the trial.
According to both Jack and Spellman, patients enrolled in XMT-1522 have HER2 solid tumors and usually their cancers have become metastatic. “To be eligible you have to have failed all other treatment options,” said Spellman.
In this kind of clinical trial, Jack and Spellman reiterated that “patient safety becomes first priority.” Dosages are escalating throughout the trial but it is done while maintaining safety for the patient.
Jack told us their current objective “is to get this hold lifted and enroll new patients.” Both Spellman and Jack stated that Mersana is “working aggressively” with clinical investigators to move forward and get the partial hold lifted.
“1522 [XMT-1522] can offer a very important therapy,” said Spellman. According to Spellman and Jack, Mersana wants to move forward with this trial to provide this therapy to new and current patients with advanced HER2-positive breast and gastric cancer.