**Study Overview:** This study looks at how safe and tolerable a drug called *talquetamab* is when used with other cancer treatments for people with *multiple myeloma*, a type of blood cancer. The goal is to find the right dose of talquetamab in these combinations. **Key Points:** - **Participation involves several visits** to monitor safety and effectiveness. - **Potential benefits and risks** are associated, including possible side effects from the drug combinations. - **Eligibility requirements** include specific health criteria and lifestyle adherence. **Eligibility:** Participants must have been diagnosed with multiple myeloma and have measurable disease markers, like certain proteins in their blood or urine. They should also have a good general health status, as determined by specific tests and scores. Women who can have children must pass pregnancy tests and agree to follow strict pregnancy prevention plans. **Exclusions:** Participants cannot join if they had certain vaccines recently, used high doses of steroids, or have other specific health conditions like brain involvement by the cancer, HIV, or recent strokes or seizures. This study is a chance to contribute to cancer research and possibly receive a new treatment. However, it's important to consider the commitment and risks involved.