A new therapy that prompts the immune system to kill cancer cells in the bone marrow was successful in 73 percent of patients in two clinical trials, according to researchers at The Tisch Cancer Institute at the Icahn School of Medicine at Mount Sinai in New York, USA .
The therapy, known as a bispecific antibody, attaches to both T cells and multiple myeloma cells and directs T cells – white blood cells that can be used to fight disease – to destroy multiple myeloma cells.
The success of commercially available immunotherapy, called talquetamab, it was seen even in patients whose cancer was resistant to all approved therapies for multiple myeloma.
The new therapy uses a different target than other approved treatments, a receptor expressed on the surface of cancer cells known as GPRC5D, according to Medical Xpress.
Talketamag immunotherapy, the first type of effective therapy in patients with multiple myeloma
All study participants had previously been treated with at least three different therapies without achieving lasting improvement, suggesting that talquetamab could offer new hope for patients with hard-to-treat multiple myeloma.
“This means that almost three-quarters of these patients now have a new chance at life. Talquetamab induced a substantial response among patients with heavily pretreated, relapsed, or refractory multiple myeloma, the second most common blood cancer. It is the first bispecific agent to target the GPRC5D protein in patients with multiple myeloma,” said Ajai Chari, director of Clinical Research in the Multiple Myeloma Program at The Tisch Cancer Institute.
About all myeloma patients who receive standard therapies relapse.
A 73% response rate
Patients received a variety of doses of therapy, either intravenously or injected under the skin; future studies will focus on doses administered just under the skin, either weekly or every other week.
The response rate of the two groups included in the study was 73%, according to Dr. Chari. More than 30% of patients in both groups had a complete response, and nearly 60% had a “very good partial response” or better (which indicates a substantial reduction in cancer, but not necessarily to zero).
The median duration to response was one to two months in both groups, and the duration of response to date is 9.3 months with weekly dosing.
Few patients discontinued treatment due to side effects
Side effects were relatively common but usually mild. About three-quarters of patients experienced cytokine release syndrome, which is a cluster of symptoms, including fever, common with immunotherapies.
About 60% experienced skin-related side effects such as rashes, about half reported taste changes, and about half reported nail disorders. The researchers stated that very few patients (5 to 6%) discontinued treatment with talquetamab because of side effects.
Dr. Chari explained that the response rate observed in the study is higher than that of most therapies available today. The fact suggests that talquetamab it could offer a viable option for patients whose myeloma no longer responds to most available therapies, offering a chance to prolong life.
The study explaining the new type of therapy was published in New England Journal of Medicine.