A Study to Investigate the Safety and Efficacy of SAR446523 Injected Subcutaneously in Adult Participants With Relapsed/Refractory Myeloma

This study is looking for adults who have been diagnosed with multiple myeloma and whose cancer can be measured. For women and men, it's important to use birth control methods as advised by the study team.

To join the first part of the study (finding the right dose), you must have already tried at least three different treatments for your myeloma, and your cancer must have either come back or not responded to those treatments. It's okay if you've had certain other types of myeloma drugs before.

For the second part of the study (testing the best dose), you also need to have tried at least three different treatments, including specific types of drugs like certain anti-inflammatory medicines, proteasome inhibitors, and anti-CD38 antibodies, and your cancer must have come back or not responded to them. However, for this part, you can't have had a specific older type of drug called anti-GPRC5D therapy. There are also general health requirements, like having good organ function and not having other serious health conditions, or certain types of nerve damage or problems affecting the brain.

If you decide to take part in this study, the timing of your last visit can vary, as the study will continue until the last person has completed their final check-up. You'll keep receiving the study treatment, SAR446523 (given as an injection under the skin), for as long as it seems to be helping, and you're not experiencing difficult side effects. You, or your doctor, can decide to stop the treatment at any time if it's no longer suitable or if you wish to withdraw.