The augmented Berlin-Frankfurt-Muenster (ABFM) regimen with Capizzi-based methotrexate/pegaspargase (C-MTX) yielded excellent event-free survival (EFS) and overall survival (OS) rates in a study of patients with newly diagnosed pediatric T-cell lymphoblastic lymphoma (T-LL; J Clin Oncol. 2020 Jun 17. Epub ahead of print).

“The Children’s Oncology Group (COG) protocol AALL0434 evaluated the safety and efficacy of multi-agent chemotherapy with [C-MTX] in patients with newly diagnosed pediatric [T-LL] and gained preliminary data using nelarabine in high-risk patients,” wrote Robert J. Hayashi, MD, Division of Pediatric Hematology/Oncology, Washington University School of Medicine, St Louis, Missouri, and colleagues.

A total of 299 patients (age, 1-31 years) were enrolled in the study; high-risk (HR) patients had ≥1% minimal detectable disease (MDD) in the bone marrow at diagnosis or had previously been given steroid treatment.

According to the investigators, induction failure was classified as a patient not achieving a partial response (PR) by the end of the 4-week induction.

All patients in the study were given the ABFM C-MTX regimen, while HR patients were randomized to receive (or not receive) six 5-day courses of nelarabine incorporated into ABFM.

Notably, Dr Hayashi et al assigned all patients with induction failure to receive ABFM C-MTX plus nelarabine.

At the end of the induction period, approximately 99% of evaluable patients had at least a PR. The 4-year EFS and OS rates were 84.7% ± 2.3% and 89.0% ± 2.0%, respectively.

From the end of the induction period, the 4-year disease-free survival (DFS) was 85.9% ± 2.6%, and there was no difference in DFS observed between the HR and standard-risk arms (P = .29) or by treatment regimen (P = .55).

“Disease stage, tumor response, and MDD at diagnosis did not demonstrate thresholds that resulted in differences in EFS,” Dr Hayashi and co-investigators wrote, adding that nelarabine did not yield any advantage in HR patients.

“COG AALL0434 produced excellent outcomes in one of the largest trials ever conducted for patients with newly diagnosed T-LL. The COG ABFM regimen with C-MTX provided excellent EFS and OS without cranial radiation,” they concluded.—Hina M. Porcelli