On day 4 at ASCO, several notable abstracts from new and ongoing clinical trials were discussed in oral sessions. These included:
Dr. Andrew Yee from Mass. General Hospital Cancer Center reported on a Phase 2 study of Pomalyst, Velcade, and dex in RRMM patients. 33 patients who had prior Revlimid and Velcade treatment were dosed. They found:
- Best overall response rate was 52%
- Median PFS was 9.7 months
They concluded that treatment was well tolerated with manageable toxicity and confirms retreatment with Velcade and an IMiD is an option for many patients.
Dr. Saad Usmani of Levine Cancer Center in Charlotte NC reported the results of the PAVO study, which is examining the subcutaneous dosing of Darzalex in RRMM patients. Darzalex dosed in this manner can be injected over 3-5 minutes. They found:
- The 25 patients in this study tolerated the subcutaneous dosing quite well, with low Infusion related reactions
- Patients achieved 44% ORR, similar to Darzalex administered IV
- Administration of Darzalex subcutaneously vs IV offers increased convenience to MM patients with no change in efficacy
This is exciting because of the expontentially faster administration without sacrificing efficacy.
Dr. Ajai Chari of Mt. Sinai in NYC reported on a Phase 1b study of isatuximab (ISA), an anti-CD38 antibody, similar to Darzalex that is currently in Phase III clinical trials, in combination with Kyprolis in RRMM.
- A total of 33 patients with at least 2 prior lines of therapy were dosed with Isa-Kd
- ORR was 66%
- The combination of ISA with Kd appears safe and has encouraging anti-MM activity
- Testing will now advance to a Phase 3 trial of ISA-Kd vs Kd
Dr. Sikander Ailawadhi of Mayo Clinic in Jacksonville FL performed a study to rigorously compare low (27 mg/m2) vs high dose (56 mg/m2) of Kyprolis in RRMM.
- Data from 121 patients was collected
- High dose Kyprolis did not provide any PFS or OS benefit over 32 month follow up
- Certain adverse events were more common with high dose Kyprolis; cardiac adverse events were not significantly different between low and high dose groups
Ongoing trials looking at dose and scheduling of Kyprolis will help define how it should be used in RRMM to optimize patient outcomes. These data suggest, however, that higher dosing may not lead to better response.
Dr. Roland Fenk of University Hospital Duesseldorf performed a study to look at the dosing of Revlimid during maintenance therapy in NDMM patients after high dose therapy and ASCT. 188 patients studied received either 25 mg or 5 mg Revlimid until disease progression occurred, after a uniform 25 mg dose for 6 months following ASCT. They found:
- Many patients in the high dose group required dose reductions over the course of therapy
- Dose reductions were due mainly to low blood counts
- Patients receiving the low dose had shorter progression free survival but also had fewer side effects
- Obtaining long term overall survival data will be helpful in determining whether the high dose regimen should be reconsidered.
Additional studies are needed, particularly to understand whether some patients, based on their subtype or disease characteristics, may benefit from either the higher or lower dose.
Dr. Francesca Gay from University of Torino in Italy reported on a study of Kyprolis-Revlimid-dex vs Kyprolis Cyclophosphamide (Cytoxan)-dex in newly diagnosed MM patients (NDMM).
- 474 patients were equally divided between KRd or KCd arms
- Rates of response better than VGPR (75% vs 60%) were higher in the KRd arm vs the KCd arm
- MRD negativity was attained in in 56% of KRd vs 29% of KCd patients
This study provided additional evidence of the strong synergy between Kyprolis and Revlimid, even in the upfront setting.