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SAR446523, an investigational antibody targeting GPRC5D, received FDA orphan drug status and is in phase 1 trials for relapsed/refractory multiple myeloma.
The U.S. Food and Drug Administration (FDA) has granted orphan drug designation to SAR446523 for the potential treatment of patients with relapsed or refractory multiple myeloma, according to a news release from Sanofi.
SAR446523 is a type of antibody therapy designed to help the immune system find and destroy cancer cells by targeting a protein called GPRC5D.
“The orphan drug designation is a significant milestone in our ongoing efforts to develop innovative treatments in multiple myeloma,” Dr. Alyssa Johnsen, Global Therapeutic Area Head, Immunology and Oncology Development at Sanofi, said in the news release. “This underscores our commitment to multiple myeloma, a disease for which we have acquired strong expertise with the development of another widely used and approved immunotherapy treatment.”
SAR446523 is still being studied, and its safety and effectiveness have not yet been reviewed or approved by any regulatory agency.
SAR446523 is an investigational monoclonal antibody designed to target GPRC5D, a protein highly expressed on plasma cells. It features an engineered Fc (fragment crystallizable) domain to boost immune cell–driven killing of cancer cells. This novel approach aims to improve outcomes for people with relapsed or refractory multiple myeloma, a rare and difficult-to-treat blood cancer, according to the release. The drug is being studied as a subcutaneous injection in an ongoing phase 1 trial.
The first-in-human phase 1 study is evaluating SAR446523 in people with relapsed or refractory multiple myeloma. The trial includes two parts. In the dose escalation phase, up to six dose levels of SAR446523 will be tested to determine the maximum administered dose, maximum tolerated dose, and a recommended dose range for two dosing regimens. In the dose optimization phase, participants will be randomly assigned in a 1:1 ratio to one of the selected dose regimens from the first phase using interactive response technology.
The goal is to identify the optimal dose for future studies. Participants may continue treatment until their disease progresses, side effects become unacceptable, or either they or their investigator decide to stop. The study will continue until the last participant completes their final visit.
This study is for people diagnosed with multiple myeloma whose disease can be measured. To join, participants must have tried at least three previous treatments, and their cancer must have returned, not responded to treatment, or they couldn’t tolerate those therapies.
In the first part of the study, it’s okay if participants have had certain prior treatments targeting GPRC5D or the gene BCMA. In the second part, prior treatment targeting GPRC5D is not allowed.
People cannot join if they have a performance status that limits their daily activities, certain other serious health conditions like amyloidosis or plasma cell leukemia, or cancer that has spread to the brain or its lining. They also can’t have had recent myeloma treatments or natural killer cell therapies within the past several weeks, or if their organs or bone marrow don’t function well. Anyone with serious other illnesses that could affect the study is also excluded.
Multiple myeloma is considered a rare disease, yet it is the second most common hematologic malignancy worldwide, with more than 180,000 people diagnosed each year. Despite available treatments, multiple myeloma remains incurable, with an estimated five-year survival rate of 62% for newly diagnosed patients.
New frontline therapeutic options are needed for all patients, especially those who are transplant ineligible, due to high attrition rates in later lines of therapy. Because multiple myeloma cannot be cured, most patients will eventually relapse and stop responding to the treatments they have received.
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