This is a phase 1/2a trial. Since this is an AHSCT conditioning regimen trial, only one cycle of therapy will be administered for each subject.
PHASE 1 The phase 1 component has a typical 3+3 design.
* Initially up to three subjects will be enrolled in each cohort starting at cohort 0 in the table below.
* If no dose limiting toxicity (DLT) is noted among the 3 initial subjects, 3 additional patients will be accrued at the subsequent cohort.
* If 1/3 subjects experience DLT, 3 additional subjects will be accrued at the cohort. If no additional DLT occur, accrual will continue at the subsequent cohort.
* If 2 or more subjects experience DLT in a given cohort, the dose will be considered higher than the maximum tolerated dose (MTD) and the immediately lower dose will be considered the MTD.
* If accrual is completed in cohort 4 with 0/3 or 1/6 DLT, the MTD will be considered "not reached" and cohort 4 will be expanded in the phase 2 of the trial.
* If 2 subjects experience DLTs in cohort 0, patients will be accrued in cohort -1, one subject at a time, with the subsequent subject only being accrued once the current subject has completed the DLT period (transplant day 30). The doses in cohort -1 will be considered the MTD if 0/3 or 1/6 subjects experience DLT.
* If ≥ 2 subjects experience DLT in cohort -1 the study will be interrupted without proceeding to phase 2a and the combination of carfilzomib and high dose melphalan will be considered too toxic.
PHASE 2 Once the MTD for the combination of carfilzomib and high dose melphalan with AHSCT is found, there will be expansion of the MTD cohort so that 28 individuals will be treated at the MTD of carfilzomib and high dose melphalan.
Screening - Subjects likely to meet eligibility criteria will be offered participation in the study after the investigator verifies with the registration system that there is a current available slot (phase 1). Subjects will sign informed consent prior to any protocol associated procedure. Screening procedures are outlined in Table 3 and will 1) ensure that subject meets all the eligibility criteria, 2) obtain disease assessment to allow efficacy measurements, 3) assess baseline toxicity and 4) provide initial biological samples for pharmacodynamic and correlative studies.
Treatment- Subjects will receive the appropriate dose of carfilzomib (according to assigned cohort in phase 1 and at the determined MTD in phase 2) on days -3 and -2. Carfilzomib will be infused over 30 minutes. On day -2, with 60 to 120 minutes of the end of infusion of carfilzomib, subjects will receive 200 mg/m2 of intravenous melphalan as an intravenous push or a fast infusion. Prophylaxis of chemotherapy induced nausea and vomiting will follow institutional guidelines.
Infusion of autologous cells- Infusion of autologous hematopoietic stem cells will occur on day 0 and follow institutional SOP.
Follow up phase - On day 1 following HSCT patients will receive pegfilgrastim 6 mg subcutaneously as per institutional standard of care aiming at faster engraftment. The follow up phase will last 100 days and will consist of standard post transplantation supportive care and monitoring of adverse events (AE's). For the phase 1 component of the study, dose-limiting toxicities will be captured during the first 30 days after transplantation (DLT period). Patients without progression may continue with carfilzomib maintenance therapy.
Patients will either be randomized in blocks of two to either maintenance therapy Arm 1= AB (two cycles of A followed by two cycles of B), or maintenance therapy Arm 2= BA (two cycles of B followed by two cycles of A). Maintenance regimen A will consist of carfilzomib 36 mg/m2 infused over 30 minutes on days 1,8,15. Maintenance regimen B will consist of carfilzomib 36 mg/m2 infused over 30 minutes on days 1, 2, 15 and 16. Each cycle will have 4 week duration. The first four maintenance therapy cycles will be dictated by a randomized assignment at time of study registration to maintenance therapy. For both maintenance therapy arms, a patient preference questionnaire will be administered to the patient upon completion of the 4th cycle. The remaining 8 cycles (cycles 5-12) will be administered according to the regimen schedule preferred by the patient as documented on the patient preference questionnaire.
Disease assessment- Disease assessment will occur at day 100 (+/- 7 days) and will consist of serum protein electrophoresis, serum and urine immunofixation, 24h urine protein electrophoresis, serum free light chains, bone marrow aspiration and biopsy, complete blood counts and metabolic panel.
