BOSTON – Subcutaneous daratumumab in combination with standard care is comparable to intravenous daratumumab plus standard care in patients with newly diagnosed or relapsed/refractory multiple myeloma, according to a speaker at the International Myeloma Workshop.
Overall response rates (ORRs) observed with subcutaneous daratumumab–based combinations in the phase 2 PLEIADES trial were similar to ORRs observed with intravenous daratumumab–based combinations in three other trials – GRIFFIN, ALCYONE, and POLLUX.
, of the Icahn School of Medicine at Mount Sinai, New York, presented these findings at the workshop, which is held by the International Myeloma Society.
In the, researchers tested subcutaneous daratumumab (D) in combination with:
- Bortezomib, lenalidomide, and dexamethasone (VRd) in transplant-eligible patients with newly diagnosed multiple myeloma
- Bortezomib, melphalan, and prednisone (VMP) in transplant-ineligible patients with newly diagnosed multiple myeloma
- Lenalidomide and dexamethasone (Rd) in patients with relapsed/refractory multiple myeloma who had received at least one prior line of therapy.
There were 67 patients in the D-VRd arm, and they had a median age of 59 years (range, 33-76 years). There were 67 patients in the D-VMP arm, and they had a median age of 75 years (range, 66-86 years). There were 65 patients in the D-Rd arm, they had a median age of 69 years (range, 33-82 years), and they had received a median of one (range, one to five) prior therapies.
Dr. Chari noted that baseline characteristics in this study were “pretty comparable” to characteristics in the studies of intravenous daratumumab. He also pointed out that the median administration time for subcutaneous daratumumab was 5 minutes in this study, which is “substantially” shorter than the typical administration time for intravenous daratumumab.
The median number of treatment cycles was 4 (range, 1-4) in the D-VRd arm, 8 (range, 1-10) in the D-VMP arm, and 12 (range, 1-15) in the D-Rd arm. The median duration of treatment was 2.6 months, 10.6 months, and 11.1 months, respectively.
The proportion of patients who discontinued treatment was 3% in the D-VRd arm, 10.4% in the D-VMP arm, and 20% in the D-Rd arm.
Dr. Chari said response rates in the three arms of PLEAIDES were similar to response rates in corresponding groups from the studies of intravenous daratumumab–based combinations.
After four induction cycles, subcutaneous D-VRd produced an ORR of 97% in PLEAIDES, and intravenous D-VRd produced an ORR of 98% in the GRIFFIN trial ().
Subcutaneous D-VMP produced an ORR of 89.6% at a median follow-up of 11 months. In the ALCYONE trial, intravenous D-VMP produced an ORR of 90.9% at a median follow-up of 16.5 months ().
Subcutaneous D-Rd produced an ORR of 93.8% at a median follow-up of 11.2 months. In the POLLUX trial, intravenous D-Rd produced an ORR of 92.9% at a median follow-up of 13.5 months ().
All patients in PLEIADES had treatment-related adverse events (TEAEs). The rate of serious TEAEs was 28.4% in the D-VRd arm, 38.8% in the D-VMP arm, and 47.7% in the D-Rd arm. The rate of grade 3/4 TEAEs was 56.7%, 68.7%, and 83.1%, respectively. There was one fatal TEAE in the D-VRd arm, two fatal TEAEs in the D-VMP arm, and two in the D-Rd arm.
Infusion-related reactions occurred in 7.5% of all patients (15/199). Most infusion-related reactions were grade 1/2. One patient had a grade 3 reaction, and there were no grade 4 reactions. The median time to onset was 3.3 hours.
“Daratumumab in combination with standard of care, when given subcutaneously, demonstrated comparable clinical activity and safety and corresponded to daratumumab intravenous–containing regimens,” Dr. Chari said. “These results support the use of flat-dose 1,800 mg [subcutaneous daratumumab] in combination with standard treatment regimens.”
The PLEIADES trial was sponsored by Janssen Research & Development. Dr. Chari reported relationships with Janssen and several other companies.
SOURCE: Chari A et al. IMW 2019, .