EHA 2018 | Efficacy of 2-year rituximab maintenance vs observation in patients with MZL

On Friday 15^th June an oral abstract session took place at the 23^rd Congress of the European Hematology Association (EHA). Abstract S102 was presented by Mathias Rummel, University Hospital Giessen, Germany, on the outcomes of the StiL NHL7-2008 MAINTAIN trial.

The MAINTAIN trial is a prospective, randomized, multi-center phase II study assessing two-years rituximab maintenance compared with observation after first-line treatment with bendamustine plus rituximab (B-R) in patients with non-Hodgkin lymphoma (NHL) and small lymphocytic leukemia. The results presented focused on patients with marginal zone lymphoma (MZL). The objective of the StiL NHL7-2008 study was to demonstrate progression-free survival (PFS) improvement of 2-year rituximab maintenance over observation after induction with B-R.

Study Overview

• The primary endpoint was progression-free survival (PFS) and the secondary endpoints were overall survival (OS), time to next treatment (TTNT), response rates, adverse events, short- and long-term toxicity, secondary primary malignancies
• 104 patients diagnosed with MZL were randomized to receive either B-R and then observation (n = 51) or B-R and then 2 years’ rituximab maintenance every 2 months (n = 53)

Key Findings

• After 78-month median follow-up, the PFS for observation was a median of 92 months vs R-maintenance was not yet reached, hazard ratio 0.33 (95% CI, 0.16–0.71), P = 0.0047
• After 78-month median follow-up the difference in OS was not significantly different. For the observation group the median OS was not yet reached for both observation and R-maintenance, hazard ratio 0.53 (95% CI 0.20–1.43), P = 0.2143
• The most frequent grade ≥3 adverse events (AEs) for observation vs R-maintenance
  • Infections = 4% vs 6%
  • Gastrointestinal = 0% vs 6%
• 28 patients died during the study due to lymphoma (6%), infection (4%), secondary malignancy (2%) and other/unknown reason (8%)

Dr Rummel concluded that the 2 years R-maintenance cohort had prolonged PFS after B-R but there was no statistically significant difference in OS between the two groups. He noted that the study confirmed high anti-lymphoma activity of B-R in patients with MZL. Additionally, Dr Rummel said that B-R followed by R-maintenance appeared to be a very effective treatment approach in patients with nodal and splenic MZL.