A pilot phase II study of ofatumumab monotherapy for extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) lymphoma

Hematol Oncol. 2018 Feb;36(1):49-55. doi: 10.1002/hon.2454. Epub 2017 Jul 10.

Abstract

These are the final results of the Ofatumumab in MALT lymphoma study (O-MA 1), a pilot phase II trial evaluating the capacity and safety of ofatumumab to induce objective responses in patients with Helicobacter pylori eradication refractory or extragastric MALT lymphoma. Ofatumumab was given at 4 weekly doses (1000 mg) followed by 4 doses at 2-month intervals starting at week 8. According to protocol, a total of 16 patients were recruited (median age 69 years; range 38-85). Thirty one percent (5/16) of patients had primary gastric MALT lymphoma while the remaining 69% (11/16) presented with extragastric manifestations. Seventy-five percent (12/16) had localized lymphoma and 4 patients disseminated disease. The overall response rate to treatment with ofatumumab was 81% (13/16), with the median time to best response being 5.5 months. In detail, 50% (8/16) achieved complete remission; 31% (5/16), partial remission; and 19% (3/16), disease stabilization as best response. However, 1 patient with gastric lymphoma and complete remission at second restaging had a relapse at final assessment but ongoing complete remission during further follow-up. Tolerability was excellent accept low-grade infusion reactions occurring in 86% (14/16). At a median follow-up time of 25 months only 1 patient has relapsed suggesting durable responses in the majority of patients. This pilot trial shows clearly that ofatumumab is active and safe for the treatment of MALT lymphoma.

Keywords: MALT lymphoma; extranodal lymphoma; indolent lymphoma; monoclonal antibody; ofatumumab.

Publication types

  • Clinical Trial, Phase II

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antibodies, Monoclonal / pharmacology
  • Antibodies, Monoclonal / therapeutic use*
  • Antibodies, Monoclonal, Humanized
  • Antineoplastic Agents / pharmacology
  • Antineoplastic Agents / therapeutic use*
  • Female
  • Humans
  • Lymphoma, B-Cell, Marginal Zone / drug therapy*
  • Lymphoma, B-Cell, Marginal Zone / pathology
  • Male
  • Middle Aged
  • Pilot Projects

Substances

  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Humanized
  • Antineoplastic Agents
  • ofatumumab