Listeria Risk Soars With Daratumumab for Multiple Myeloma

By David Douglas

December 05, 2019

NEW YORK (Reuters Health) - Patients with multiple myeloma receiving daratumumab-based therapy are at highly increased risk of infection by Listeria monocytogenes, according to researchers in Canada.

"Although previous clinical trials have demonstrated that daratumumab is relatively safe and associated with only a mild infection risk, we found that daratumumab is associated with a significantly increased risk of listeriosis," Dr. Rodger E. Tiedemann of Princess Margaret Cancer Centre in Toronto told Reuters Health by email.

The findings, online November 27 in JAMA Oncology, were based on an analysis of data from a Listeria outbreak at a commercial restaurant in Dr. Tiedemann's institution.

The study covered a period of nine months in 2018 during which time there were more than 85,000 outpatient visits to the hospital. In total, Dr. Tiedemann and his colleagues identified seven people with listeriosis associated with patronage of the eatery in question. All had cancer and four had multiple myeloma.

Although use of corticosteroids may increase Listeria susceptibility, say the researchers, there were no cases in patients with myeloma who were receiving corticosteroids without daratumumab. Overall the 40 patients who were receiving daratumumab accounted for fewer than 0.3% of potentially exposed individuals, but comprised 43% of cases.

"Daratumumab-treated myeloma patients experienced a 75-fold increased risk of Listeriosis compared to other myeloma patients and a 340-fold risk compared to all other cancer patients. No healthy individuals were infected," said Dr. Tiedemann.

"The findings," he continued, "are consistent with previously-reported mouse studies in which mice lacking the daratumumab target (CD38) were also found to be specifically vulnerable to Listeria infection."

Dr. Tiedemann observed, "The study has several key clinical implications. Firstly, patients receiving daratumumab should avoid foods that may contain Listeria (such as unpasteurized dairy products, undercooked meats or unwashed vegetables). Secondly, treatment of daratumumab-exposed patients with antibiotic prophylaxis should be considered."

"Finally," he concluded, "physicians need to be vigilant for listeriosis in daratumumab-treated patients and offer early treatment. Unfortunately, once listeriosis is established in vulnerable patients it can rapidly cause major complications including brain abscess, coma and death."

Dr. Morie A. Gertz, a professor of medicine and a consultant in the division of hematology at Mayo Clinic in Rochester, Minnesota, told Reuters Health by email, "Patients receiving daratumumab have an increased infection risk."

"This article indicates the need for dietary precautions avoiding unpasteurized product ingestion," added Dr. Gertz, who was not involved in the study.


JAMA Oncol 2019.