Thalidomide and prednisolone versus prednisolone alone as consolidation therapy after autologous stem-cell transplantation in patients with newly diagnosed multiple myeloma: final analysis of the ALLG MM6 multicentre, open-label, randomised phase 3 study

Limited benefits of thalidomide and dexamethasone maintenance after autologous stem cell transplantation in newly diagnosed multiple myeloma patients: a prospective phase II multi-center study in Korea

Although the clinical outcome of newly diagnosed multiple myeloma has improved with maintenance therapy, maintenance with novel agents is not always available depending on medical expenses or drug accessibility. We intended to investigate the efficacy and toxicity of thalidomide/dexamethasone maintenance in Korean patients. In this multicenter phase 2 study, patients with newly diagnosed myeloma who underwent induction chemotherapy followed by autologous stem cell transplantation (ASCT) were enrolled to receive maintenance treatment of 100mg thalidomide daily for 28 days and 40mg dexamethasone daily for 4 days each cycle. Maintenance was given up to 12 cycles. The primary endpoint was a 1-year event free survival (EFS) rate. It was assumed that EFS at 1-year would be 91% with thalidomide and 1-year EFS below 82% would be of no effect. A total of 43 patients were consecutively enrolled (median age, 58 years [range, 34 - 65]; male, n = 31). With a median follow-up duration of 17.3 months (range, 1.1 - 32.2), EFS at 1 year was 65.1% (95% confidence interval [CI], 48.9 - 77.3). PFS and OS at 1 year was 85.6% (95% CI, 70.7 - 93.3) and 90.4 (95% CI, 76.3 - 96.3), respectively. In terms of side effects, 39 patients (90.7%) experienced adverse events (AEs) of any grade, and 14 patients (32.6%) experienced grade 3 or 4 adverse events. 15 patients (34.9%) failed to complete 12 cycles of maintenance, and the most common reason for premature termination was AEs (n = 6). In Korean patients the benefits of thalidomide maintenance does not seem to outweigh the toxicity of thalidomide, especially in high-risk MM. Considering the long clinical course of MM, preservation of quality of life and finances might be more beneficial for subsequent MM treatment.

The role of novel agents for consolidation after autologous transplantation in newly diagnosed multiple myeloma: a systematic review

Despite the increasing inclusion of novel agents within the multiple myeloma (MM) treatment sequence, their role for posttransplant consolidation therapy remains unclear. We systematically reviewed studies evaluating the efficacy of novel agent consolidation. We identified 11 citations on 12 prospective comparative studies, and 5 citations were single-arm or comparative studies with preliminary results. Nine different regimens were evaluated in 5905 patients. Risk assessment yielded serious risk of bias and heterogeneity across study designs was high. Irrespective of the regimen, deepened responses after consolidation were seen and improvements were more pronounced with multi-agent consolidation. Bortezomib, thalidomide, and dexamethasone improved long-term survival versus duplet consolidation, including in patients with high-risk cytogenetics. The addition of daratumumab to triplet regimens yielded modestly improved responses with significantly increased rates of minimal residual disease negativity but survival results were limited by short follow-up. In high-risk MM, responses were not different, whereas progression-free survival appeared to be improved with consolidation therapy, challenging the association of response and overall outcome in this subgroup. Our findings highlight the necessity of longer follow-up and consistent reporting to ensure comparability of studies to enable better evidence assessment and to identify patients benefitting from consolidation therapy.

Thalidomide maintenance therapy in Japanese myeloma patients: a multicenter, phase II clinical trial (COMET study)

A prospective, multicenter, phase II study was performed to assess the efficacy and safety of thalidomide maintenance therapy at different doses in Japanese multiple myeloma (MM) patients. This study included 34 patients (median age, 74 years) who were previously treated with not more than three prior therapies and whose response status was evaluated as at least stable disease. They were randomized into Group A (no maintenance; 12 patients), Group B (50 mg thalidomide maintenance; 12 patients), and Group C (100 mg thalidomide maintenance; 10 patients), respectively. Thalidomide maintenance therapy resulted in improved depth of response in three cases (13.6%) and sustained response after induction therapy in eight cases (36.4%). Two-year progression-free survival (PFS) was 25.0%, 33.3%, and 77.8% in Groups A, B, and C, respectively, and was significantly higher in Group C than in Group A (p = 0.005). There was no difference in the incidence of hematological or non-hematological adverse events between Groups B and C. The current study demonstrates that maintenance with daily thalidomide at 100 mg, but not 50 mg, improved depth of response and prolonged PFS, and that this treatment was feasible for use in Japanese MM patients.