A Study to Compare Pharmacokinetics, Efficacy and Safety of Subcutaneous CT-P44 and Darzalex Faspro in Combination With Lenalidomide and Dexamethasone in Patients With Refractory or Relapsed Multiple Myeloma

This study is comparing CT-P44 (a biosimilar version of daratumumab) to the already-approved Darzalex Faspro (daratumumab), both given under the skin (subcutaneously) in combination with lenalidomide and dexamethasone, for patients with relapsed or refractory multiple myeloma. The goal is to show that CT-P44 works as well and is as safe as Darzalex Faspro. **You may be eligible if...** - You are 18 years or older - You have been diagnosed with multiple myeloma that has relapsed (come back) or is refractory (no longer responding to treatment) - You have achieved at least a partial response to at least one prior treatment - Your disease has progressed on your most recent line of therapy **You may NOT be eligible if...** - You have previously received daratumumab or any other anti-CD38 targeted therapy - Your disease is resistant or intolerant to lenalidomide - Your overall health or other conditions would make study participation unsafe or inappropriate Talk to your doctor to see if this trial is right for you.