Primary Purpose Phase Ib. To determine the Maximum Tolerated Dose (MTD) and establish the Recommended Phase IIa Dose (RP2D) of Purinostat Mesylate for Injection combined with fixed-dose Pomalidomide Capsules and Dexamethasone in patients with relapsed or refractory multiple myeloma.
Phase IIa. To further evaluate the safety and tolerability of Purinostat Mesylate for Injection at the RP2D combined with fixed-dose Pomalidomide Capsules and Dexamethasone in patients with relapsed and refractory multiple myeloma (RRMM).
Secondary Objectives Phase Ib
1. To evaluate the safety and tolerability of Purinostat Mesylate for Injection combined with fixed-dose Pomalidomide Capsules and Dexamethasone in the treatment of relapsed or refractory multiple myeloma. 2. To assess the pharmacokinetic (PK) parameters of the combination therapy in patients with relapsed or refractory multiple myeloma. 3. To observe the preliminary efficacy of the combination therapy in patients with relapsed or refractory multiple myeloma.
Phase IIa
1. To evaluate the preliminary efficacy of the combination therapy in patients with relapsed and refractory multiple myeloma (RRMM). 2. To characterize the population pharmacokinetic (PPK) profile of the combination therapy in patients with relapsed or refractory multiple myeloma (RRMM).
Diagnosed with multiple myeloma (MM) by reference to the diagnostic criteria of the Chinese Guidelines for the Diagnosis and Treatment of Multiple Myeloma (Revised 2022);
Those who have received at least one line of prior systemic antimyeloma therapy (which must include lenalidomide and proteasome inhibitors; see Appendix 4 for counts of myeloma treatment lines) and meet the definition of relapse or refractory; Definition of relapse: disease progression that occurs at least 60 days from the last treatment after the efficacy of a prior treatment regimen was evaluated at MR or better (except for those who relapsed more than 1 year after treatment); Definition of refractory: progression during prior therapy or progression within 60 days of the last treatment; or failure to achieve MR or better after at least 2 prior courses of therapy; or treatment intolerance.
Serum M protein ≥ 0.5 g/dL (5 g/L);
Urine M protein ≥ 200 mg/24h;
Those with prior antitumor therapy with histone deacetylase (HDAC) inhibitors (except cedarbenazine), antibody-coupled degradation agents (DAC), HSP90 inhibitors, or valproic acid; or those who, in the judgment of the investigator, are intolerant to treatment with the same type of drug as HDAC inhibitors, pomalidomide, thalidomide, lenalidomide, or the like (e.g., grade ≥3 rash during prior use, severe refractory myelosuppression, etc.);
Those with disease progression following prior treatment with standard dose pomalidomide;
Allergic reactions to the components of the test drug involved in this trial;
A diagnosis of non-secretory MM (defined as a subject who is completely non-secretory or who has a small amount of free light chain but the affected light chain is less than 100 mg/L), or MM in combination with amyloidosis, or plasma cell leukemia, either primary or during the course of therapy