A Study of Daratumumab With Pomalidomide, Dexamethasone, and All-Transretinoic Acid in Patients With Multiple Myeloma

Inclusion Criteria:

1. Documented multiple myeloma
2. For cohort A, patients must have been previously exposed to Dara+Len+Dex and must have achieved at least stable disease to this combination.
3. For cohort B, patients must have been exposed to Dara + Pom + Dex and must have achieved at least stable disease to this combination.
4. Histologically confirmed and relapsed multiple myeloma with measurable disease, defined by at least one of the following:

   1. Serum monoclonal protein ≥0.5 g/dL;
   2. Monoclonal protein in the urine on 24-hour electrophoresis ≥200 mg;
   3. Serum immunoglobulin free light chain (FLC) ≥10 mg/dL (100 mg/L) provided serum FLC ratio is abnormal;
   4. New of progressing biopsy proven plasmacytoma on exam or imaging; or
   5. Bone marrow plasma cells ≥20%;
5. Cycle 1 day 1 of study treatment must be within 3 months of last exposure to Daratumumab.
6. Life expectancy \>3 months
7. ECOG PS 0-2
8. Age ≥18
9. Adequate organ function, including bone marrow, renal, hepatic, pulmonary, and cardiac function based on the last assessment performed within the Screening Period, defined as:

   1. Absolute neutrophil count (ANC) ≥1,000/μL;
   2. Platelet count ≥50,000/μL, (≥30,000/μL if bone marrow plasma cells are ≥50% of cellularity);
   3. Hemoglobin ≥7.5g/dL;
   4. Creatinine clearance ≥60 mL/min (assessed as glomerular filtration rate using the Cockcroft-Gault formula);
   5. Alanine aminotransferase or aspartate aminotransferase \<3 x upper limit of normal (ULN);
   6. Total bilirubin \<2 x ULN (except for patients with Gilbert's syndrome confirmed by UGT1A1 mutation);
   7. Left ventricular ejection fraction ≥50% as assessed by echocardiography or multi-gated acquisition (MUGA) scan; and
   8. Must have a minimum level of pulmonary reserve defined as Grade \<2 dyspnea and pulse oxygenation ≥92% on room air;
10. Prior to first dose of study drug, a woman must be either:

    * Not of childbearing potential: premenarchal; postmenopausal (\>45 years of age with amenorrhea for at least 12 months or any age with amenorrhea for at least 6 months and a serum follicle stimulating hormone level \>40 IU/L or mIU/mL\]); permanently sterilized (eg, bilateral tubal occlusion \[which includes tubal ligation procedures as consistent with local regulations\], hysterectomy, bilateral salpingectomy, bilateral oophorectomy); or otherwise be incapable of pregnancy
    * Of childbearing potential and practicing a highly effective method of birth control for 4 weeks before initiating study treatment that is consistent with local regulations regarding the use of birth control methods for subjects participating in clinical studies: e.g., established use of oral, injected or implanted hormonal methods of contraception; placement of an intrauterine device or intrauterine system; barrier methods: condom with spermicidal foam/gel/film/cream/suppository or occlusive cap (diaphragm or cervical/vault caps) with spermicidal foam/gel/film/cream/suppository; male partner sterilization (the vasectomized partner should be the sole partner for that subject); true abstinence (when this is in line with the preferred and usual lifestyle of the subject) Note: If the childbearing potential changes after start of the study (e.g., woman who is not heterosexually active becomes active, premenarchal woman experiences menarche)
    * a woman must begin a highly effective method of birth control, as described above.
11. A woman of childbearing potential must have 2 negative serum (β human chorionic gonadotropin) or urine pregnancy tests during screening, the first one within 28 days prior to the first dose of study drug and the second within 24 hours prior to the first dose of study drug.
12. A man who is sexually active with a woman of childbearing potential and has not had a vasectomy must agree to use a barrier method of birth control e.g., either condom with spermicidal foam/gel/film/cream/suppository or partner with occlusive cap (diaphragm or cervical/vault caps) with spermicidal foam/gel/film/cream/suppository, and all men must also not donate sperm during the study and for 3 months after receiving the last dose of study drug.
13. Subjects must be willing and able to adhere to the prohibitions and restrictions specified in this protocol and referenced in the informed consent form (ICF).

Exclusion Criteria:

1. Major concurrent illness or organ dysfunction
2. Active GVHD requiring systemic corticosteroids in a subject who previously received allogeneic-SCT.
3. Cord compression or CNS involvement
4. Recent/Prior active malignancy requiring active therapy 2 years prior to enrollment excluding non-melanoma skin cancer.
5. Prior life-threatening hypersensitivity to daratumumab or an IMiD
6. Plasma cell leukemia
7. Pregnant or lactating females
8. Men donating sperm during study
9. Seropositive for human immunodeficiency virus (HIV)
10. Seropositive for hepatitis B (defined by a positive test for hepatitis B surface antigen \[HBsAg\]). Subjects with resolved infection (ie, subjects who are HBsAg negative but positive for antibodies to hepatitis B core antigen \[anti-HBc\] and/or antibodies to hepatitis B surface antigen \[anti-HBs\]) must be screened using real-time polymerase chain reaction (PCR) measurement of hepatitis B virus (HBV) DNA levels. Those who are PCR positive will be excluded. EXCEPTION: Subjects with serologic findings suggestive of HBV vaccination (anti-HBs positivity as the only serologic marker) AND a known history of prior HBV vaccination, do not need to be tested for HBV DNA by PCR
11. Seropositive for hepatitis C (except in the setting of a sustained virologic response \[SVR\], defined as aviremia at least 12 weeks after completion of antiviral therapy)
12. Chronic obstructive pulmonary disease (COPD) with a Forced Expiratory Volume in 1 second (FEV1) less than 50% of predicted normal