Triplet Therapy, ASCT Frontline Treatment for Multiple Myeloma
Clinicians are now trying to treat multiple myeloma similar to leukemia, according to George Somlo, MD, who discussed treatment regimens at the 2016 National Comprehensive Cancer Network (NCCN) Annual Congress on Hematologic Malignancies.
In the latest version of the NCCN multiple myeloma guidelines, triplet therapy is recommended over doublet therapy. The preferred frontline therapy for patients with multiple myeloma is induction therapy containing a proteasome inhibitor, immunomodulatory agent, and dexamethasone followed by autologous stem cell transplantation (ASCT), consolidation, and maintenance, said Dr Somlo, who is with the City of Hope Comprehensive Cancer Center in Duarte, California. The goal of primary therapy is to induce a very good partial response (VGPR) or better. In many instances, therapy will involve continued use of ASCT.
He cited a phase 3 study from Cavo and colleagues reported at the 2016 American Society of Clinical Oncology (ASCO) Annual Meeting that compared upfront ASCT with triplet therapy in 1266 patients with newly diagnosed multiple myeloma. Patients received induction therapy with a triplet regimen of bortezomib (Velcade), cyclophosphamide, and dexamethasone and then randomly assigned to receive bortezomib, melphalan, and prednisone (VMP) or high-dose melphalan followed by either a single or double ASCT. Progression-free survival was significantly prolonged in patients randomized to the high-dose melphalan plus ASCT arm. The VGPR or better rates were 84.4% vs 74.0% for the ASCT and VMP arms, respectively.
Following triplet therapy and ASCT, Dr Somlo added that maintenance therapy is an important component of treatment. Presently, the maintenance regimen choice is lenalidomide (Revilimid). He highlighted a study by Attal and colleagues also presented at ASCO that looked at lenalidomide following high-dose melphalan and ASCT in a meta-analysis. The results showed that 7-year overall survival rate was 62% with lenalidomide vs 50% for placebo.
Bortezomib is another potentially effective maintenance option, but currently data is limited for this treatment option to give it a category 1 recommendation in the NCCN guideline, he said.
As for which regimen should be used in the older population, Dr Somlo said triplet therapy has been shown to remain consistent and beneficial in this patient population, but pointed out that comorbidities and not age should be a deciding factor.