Inclusion Criteria:

• Male or female ≥18 years of age
• Prior diagnosis of MM as defined according to IMWG criteria and relapsed or refractory to the last line of therapy
• Eastern Co-operative Oncology Group (ECOG) performance status of 0 to 2
• Adequate hematological, renal and hepatic function
• Willingness to use highly effective contraceptive measures (if sexually active) with all sexual partners

Exclusion Criteria:

• Use of any investigational agent, chemotherapy, immunotherapy or anticancer agent from a previous clinical study within 14 days or 5 half-lives of first dose of study treatment, whichever is shortest; any antibody based therapy within 30 days
• Prior treatment with p300/CBP bromodomain inhibitors
• Known or suspected severe allergies to any active or inactive ingredients in the study medications (inobrodib, pomalidomide, dexamethasone) or any prior immunomodulatory drug (lenalidomide, thalidomide)
• Treatment with medicines or herbal supplements or foods (e.g. strong CYP3A4 inducers or inhibitors) that would interfere with treatment
• Major surgery within 4 weeks of the first dose of study treatment
• Live vaccine within 4 weeks of study treatment
• Active or unresolved adverse events
• Active malignancies (progressing or requiring change in treatment) in the last 24 months other than multiple myeloma
• Female patients who are pregnant or breast-feeding at any time during the study
• Any illness or medical history that would impact safety or compliance with study requirements or impact ability to interpret study data