The U.S. Food and Drug Administration (FDA) placed a partial hold on an experimental drug (emavusertib), which treats leukemia, after a patient dies in a clinical trial, according to MedCity News.

Curis, a biotechnology company focused on the development of first-in-class and innovative therapeutics for the treatment of cancer, is conducting the trial of its experimental cancer drug. It said the patient had a complication that is a known risk of the small molecule drug.

The patient experienced a complication that is a known dose-limiting toxic effect called rhabdomyolysis. Rhabdomyolysis is the breakdown or death of muscle tissue that leads to the release of muscle fiber and other contents into the blood. These substances are harmful to the kidney, causing kidney damage.

Curis released no additional details about the patient’s death, but it said the FDA asked for information about the drug’s safety and efficacy, including data about rhabdomyolysis.

Emavusertib is an orally bioavailable, reversible inhibitor of interleukin-1 receptor-associated kinase 4 (IRAK4), with potential antineoplastic, immunomodulating, and anti-inflammatory activities. It has been studied for the treatment of acute myeloid leukemia (AML) or high-risk myelodysplastic syndrome (MDS).

Curis said it has decided to halt enrollment until the leukemia study partial hold is resolved, even though the lymphoma clinical trial is unaffected by the partial hold on the drug for leukemia.

James Dentzer, Curis CEO, said, “We are committed to ensuring the safety of patients in our studies and to working collaboratively with the FDA to develop therapies that meaningfully improve and extend patients’ lives.”

“Given the clinical profile of emavusertib observed to date, we are hopeful that the study can be resumed soon, after appropriate review,” he added. “We continue to be confident in the potential of emavusertib to address the high unmet need of patients with AML or MDS.”