Elotuzumab seemed to provide clinical benefit without clinically significant toxicity when combined with bortezomib/dexamethasone (Bd) vs Bd alone in patients with relapsed/refractory multiple myeloma, according to results of a phase 2 study published in Blood.1
In this proof-of-concept open-label study, patients received elotuzumab, an immunostimulatory antibody, with Bd or Bd alone until disease progression or unacceptable toxicity. Primary endpoint was progression-free survival; secondary endpoints included overall response rate and overall survival. Efficacy and safety analyses were also performed.
A total of 152 patients were included (77 received elotuzumab/Bd; 75 received Bd), 150 were treated (75 in the elotuzumab/Bd group; 75 in the Bd group).
Results showed that progression-free survival was greater with elotuzumab/Bd vs Bd (HR, 0.72; 70% CI: 0.59 – 0.88; stratified log-rank P = .09); median progression-free survival was longer as well, 9.7 months vs 6.9 months, respectively.
An updated analysis revealed that elotuzumab/Bd-treated patients homozygous for the high-affinity FcyRLLLa allele had a median progression-free survival of 22.3 months vs 9.8 in elotuzumab/Bd-treated patients homozygous for the low-affinity allele. Patients in the elotuzumab/Bd had an overall response rate of 66% vs 63%. Patients in the elotuzumab/Bd group had very good partial response or better rate of 36% vs those in the Bd group had 27%.
Early overall survival results, based on 40 deaths showed an HR of 0.61 (70% CI: 0.43 – 0.85). A total of 60 deaths have occurred so far (28 elotuzumab/Bd; 32 Bd).
No significant adverse events occurred with elotuzumab/Bd vs Bd. The rate of grade 1/2 infusion reactions was low (5% in the elotuzumab arm) and controlled with premedication.
- Jakubowiak A, Offidani M, Pegourie B, et al. Randomized phase 2 study of elotuzumab plus bortezomib/dexamethasone (Bd) versus BD for relapsed/refractory multiple myeloma [published online ahead of print April 18, 2016]. Blood. doi: 10.1182/blood-2016-01-694604.