First meta-analysis of chemorefractory DLBCL outcomes (SCHOLAR-1)

In August, the results of the SCHOLAR-1 retrospective study were published online in Blood in an article by Michael Crump, from the Canadian Cancer Trials Group at Queen’s University, Kingston, Ontario, Canada, and colleagues. This international, retrospective, multi-cohort study included data collected from four sources, two phase III clinical trials (LYSARC-CORAL and Canadian Cancer Trials Group-LY.12) and two observational groups (MD Anderson Cancer Center and Mayo Clinic/University of Iowa).

The primary objective was to evaluate response and survival rates in refractory Non-Hodgkin Lymphoma patients including patients with DLBCL, PMBCL, and TFL. Refractory, in this study, was defined as being “progressive disease or stable disease as best response at any point during chemotherapy (>4 cycles of first-line or 2 cycles of later-line therapy) or relapsed 12 months of autologous stem cell transplantation” (ASCT). Patients must have received an anthracycline and an anti-CD20 monoclonal antibody treatment regimen to be included.

Highlights:

• Initially, 861 pts included, of which 636 met the defined refractory criteria for inclusion in the analysis set of this study
• Pooled ORR = 26% (20-31%)
• Pooled CR rate = 7% (3-15%)
• Median OS in refractory DLBCL = 6.3 months (95% CI, 5.9–7 months)
• One-year OS = 28%, Two-year OS = 20%
• Pooled subgroup analysis:
  • Primary refractory patients
    • ORR = 20% (11-34%)
    • CR = 3% (1-11%)
  • Refractory to second or later line of therapy
    • ORR = 26% (17-39%)
    • CR = 10% (5-10%
  • Relapse within 12-months of ASCT
    • ORR = 34% (24-45%)
    • CR = 15% (6-31%)

The authors stated that this data was the “largest patient-level pooled analysis to evaluate responses and OR rates in patients with refractory NHL”. The authors acknowledged the limitations of retrospective studies but stated that this data provided a ‘“benchmark” for future work. The authors then concluded that the data presented in this study demonstrated consistent poor outcomes for patients with refractory NHL, and showed that effective treatments for refractory NHL represents a significant unmet need.

Abstract:

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma. Although 5-year survival rates in the first-line setting range from 60% to 70%, up to 50% of patients become refractory to or relapse after treatment. Published analyses of large-scale outcome data from patients with refractory DLBCL are limited. The international, multicohort retrospective non-Hodgkin lymphoma research (SCHOLAR-1) study retrospectively evaluated outcomes in patients with refractory DLBCL, which, for this study, was defined as progressive disease or stable disease as best response at any point during chemotherapy (>4 cycles of first-line or 2 cycles of later-line therapy) or relapsed 12 months of autologous stem cell transplantation. SCHOLAR-1 pooled data from 2 phase 3 clinical trials (Lymphoma Academic Research Organization-CORAL and Canadian Cancer Trials Group LY.12) and 2 observational cohorts (MD Anderson Cancer Center and University of Iowa/Mayo Clinic Lymphoma Specialized Program of Research Excellence). Response rates and overall survival were estimated from the time that salvage therapy for refractory disease was initiated. Among 861 patients, 636 were included based on refractory inclusion criteria. For patients with refractory DLBCL, the objective response rate was 26% (complete response, 7%) to the next line of therapy, and the median overall survival was 6.3 months. Twenty percent of patients were alive at 2 years. Outcomes were consistently poor across patient subgroups and study cohorts. SCHOLAR-1 is the largest patient-level pooled retrospective analysis that characterizes response rates and survival for a population of patients with refractory DLBCL.