ROCHE NP39403 (BET Inhibitor): This phase I trial is trying to determine whether it is better to give a new drug (RO6870810) alone or in combination with a different anti-cancer drug (daratumumab) when treating patients with advanced Multiple MyelomaOpen-label, Multicenter, Dose-escalation/Expansion Phase Ib Study to Evaluate Safety, Pharmacokinetics, and Activity of BET Inhibitor RO6870810, Given as Mono- and Combination Therapy to Patients With Advanced Multiple Myeloma

Inclusion

• Performance status </=2 on the Eastern Cooperative Oncology Group (ECOG) scale
• Life expectancy > 3 months
• Relapsed or refractory multiple myeloma. Participants with primary refractory myeloma only allowed in dose-escalation phase of the study.
• Prior treatment: Treated with at least three prior lines of multiple myeloma therapy including a proteasome inhibitor and an immuno modulatory agent or who are double refractory to a proteasome inhibitor and an immuno modulatory agent. Prior anti-CD38 antibody (e.g., daratumumab, isatuximab) treatment is acceptable only for participants receiving monotherapy treatment.
• Prior treatment: Treated with two or more lines of prior therapy, with disease refractory to both a proteasome inhibitor and an immunomodulatory agent, and disease progression (as defined by International Myeloma Working Group (IMWG) criteria) following treatment with an anti-CD38 monoclonal antibody given as monotherapy or in combination therapy. The most recent treatment regimen must have contained an anti-CD38 monoclonal antibody.
• Treatment with prior autologous transplant is permitted
• Documented diagnosis of symptomatic multiple myeloma, as defined by the IMWG
• Measurable disease defined as at least one of the following: serum M-protein >/=1 grams/deciliter (g/dL), urine M-protein >/= 200 milligrams/24 hours (mg/24h), serum free light chain (SFLC) assay: involved SFLCs >/= 10 mg/dL (>/= 100 mg/L) and an abnormal SFLC ratio (<0.26 or >1.65).
• Female participants of childbearing potential must have a negative serum pregnancy test within the 7 days prior to the first study drug administration.
• For women of childbearing potential: agreement to remain abstinent (refrain from heterosexual intercourse) or use contraceptive methods that result in a failure rate of < 1% per year during the treatment period and for at least 2 months after the last dose of RO6870810 as monotherapy, or for at least 3 months after the last dose of daratumumab.
• For men: agreement to remain abstinent (refrain from heterosexual intercourse) or use contraceptive measures and agreement to refrain from donating sperm, as defined: With female partners of childbearing potential or pregnant female partners, men must remain abstinent or use a condom during the treatment period and for at least 4 months after the last dose of RO6870810 as monotherapy, or for at least 3 months after the last dose of daratumumab.