A Study of the Safety and Tolerability of ABBV-467 in Adult Participants With Relapsed/Refractory (R/R) Multiple Myeloma

Inclusion Criteria:

Documented diagnosis of multiple myeloma (MM).

Measurable disease defined as at least 1 of the following:

Serum monoclonal protein >= 1g/dL.
Urine M-protein >= 200mg/24 hours.
Serum immunoglobulin free light chain (FLC) >= 10 mg/dL (100 mg/L), provided serum FLC ratio is abnormal.
Relapsed after or are refractory or intolerant to all established MM therapies that are both known to provide clinical benefit and locally available.
Received at least 3 prior lines of therapy including 1 or more immunomodulatory agents, 1 or more proteasome inhibitors, and 1 or more anti-CD38 treatment-should-you-receive-monoclonal-antibodies/" >monoclonal antibodies.
Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1, or 2.
Adequate hematologic, renal and hepatic function as described in the protocol.
Echocardiogram with ejection fraction >= 50% and no other clinically significant findings that would increase the participant's susceptibility to cardiac toxicity.

Exclusion Criteria:

Prior exposure to any targeted myeloid cell leukemia-1 (MCL-1) inhibitor.
Antineoplastic therapy (including any cytotoxic, targeted and/or investigational therapy; but not including corticosteroids), within 28 days or 5 half-lives, whichever is shorter, prior to the first dose of study drug and through the last dose of study drug.
Autologous stem cell transplant within 90 days prior to start of study drug.
Allogenic stem cell transplant within 180 days prior to start of study drug.
History of acute or chronic pancreatitis.
Significant unresolved liver disease.
History of hepatitis B or human immunodeficiency virus (HIV) infection.