According to new findings from an ongoing Phase 1/2 clinical research trial, a novel investigational immunotherapy resulted in successful response rates for 73 percent of patients with multiple myeloma, a lethal form of blood cancer. Based on these encouraging findings, an application to the US Food and Drug Administration (FDA) to bring the drug to market has been submitted.
Talquetamab: what is it and how does it work?
Talquetamab, the immunotherapy being tested, is a kind of treatment known as a bispecific T-cell engager antibody. It is a fairly unusual type of immunotherapy technique.
Bispecific antibodies, as opposed to typical monoclonal antibodies, are designed to bind to two distinct antigens. Talquetamab binds to CD3, a receptor on immunological T cells, and GPRC5D, a receptor identified in high concentrations on malignant plasma cells.
The purpose of bispecific antibodies is to create a link between immune cells and cancer cells. They simultaneously put a target flag on cancer cells and provide a guide to that target for immune cells.
Although the technology has been in development for decades, bispecific antibodies have just recently entered clinical trials. There are now three FDA-approved bispecific antibody therapeutics on the market (mostly for cancer), as well as more than 100 potential antibodies in clinical trials (for everything from Alzheimer’s to diabetes).
The recently released Phase 1/2 talquetamab trial data included several hundred multiple myeloma patients who were given two different dosages and weekly or fortnightly dosing schedules. The trial discovered that 73 percent of patients responded well to the treatment across all treatment groups.
“With a median follow-up of 14.9 months (range 0.5+ to 29.0), 74.1 percent of patients treated at the SC [subcutaneous] 0.4 mg/kg dose administered weekly achieved a response, 59.4 percent achieved a very good partial response or better, 33.6 percent achieved a complete response or better and 23.8 percent achieved a stringent complete response,” reads a press release from pharmaceutical company Johnson & Johnson.
The Phase 2 study data has yet to be properly published in a peer-reviewed journal, however, The New England Journal of Medicine has just released the Phase 1 data.
According to the data, the majority of patients treated with talquetamab reported mild side effects, and only about 5 percent discontinued treatment due to such side effects.
The FDA gave talquetamab Breakthrough Therapy designation earlier in 2022, based on preliminary positive trial data. This gave the treatment precedence and hastened the approval processes. The company has recently filed a Biologics License Application with the FDA in order to bring this unique medicine to market as quickly as possible.
“We look forward to working with the [FDA] to make this available as a treatment option in the short term and continuing our longer-term investigations of talquetamab as we aim to develop additional options for patients with this complex blood cancer,” said Sen Zhuang, vice president of clinical R&D at Janssen Research & Development.
Source study: The New England Journal of Medicine— Talquetamab, a T-Cell—Redirecting GPRC5D bispecific antibody for multiple myeloma