A Study to Evaluate the Safety, Pharmacokinetics, and Activity of XmAb24306 in Combination With Cevostamab in Participants With Relapsed/Refractory Multiple Myeloma

The purpose of this study is to evaluate the safety, tolerability, pharmacokinetics, and activity of XmAb24306 in combination with cevostamab in participants with relapsed/refractory multiple myeloma (R/R MM) who have received a minimum of three prior treatments, including at least one immunomodulatory drug (IMiD), one proteasome inhibitor (PI), and one anti-CD38 monoclonal antibody.

Inclusion Criteria:Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1Life expectancy of at least 12 weeksParticipants must have received a minimum of 3 prior lines of therapy, including at least one PI, one IMiD, and an anti-CD38 monoclonal antibody.Documented evidence of progressive disease on or after the last prior therapy, or participants who were intolerant to the last prior therapy.Measurable disease, as defined by the protocolParticipants agree to follow contraception or abstinence requirements as defined in the protocolExclusion Criteria:Any anti-cancer therapy within 3 weeks prior to initiation of study treatment with exception defined by the protocolParticipants with autologous stem cell transplantation (SCT) within 100 days prior to first dose of study treatmentParticipants with prior allogeneic SCT or solid organ transplantationActive or history of autoimmune diseaseParticipants with current or history of Central Nervous System (CNS) disease, or current CNS involvement by Multiple Myeloma (MM)Significant cardiovascular diseaseParticipants with known clinically significant liver diseaseSymptomatic active pulmonary disease requiring supplemental oxygenKnown active infection requiring intravenous anti-microbial therapy within 14 days prior to first study drug administrationOther protocol defined inclusion/exclusion criteria may apply