Concurrent Temozolomide Plus Radiotherapy Fails to Improve Survival for Patients With Non-Codeleted Anaplastic Glioma
According to results from the phase 3 CATNON trial, concurrent temozolomide plus radiotherapy did not improve survival results compared to adjuvant temozolomide plus radiotherapy among patients with non-codeleted anaplastic glioma.
These data were first presented by Martin Van Den Bent, MD, Erasmus Medical Centre Cancer Institute, Rotterdam, Netherlands, at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago, Illinois.
In this study, 751 newly diagnosed patients with non-codeleted anaplastic glioma were enrolled to receive 59.4 Gy of radiotherapy alone or in combination with concurrent or adjuvant temozolomide or 59.4 Gy of radiotherapy with both concurrent and adjuvant temozolomide. The primary end point was overall survival (OS) in the intention-to-treat population and in patients with IDH-mutated (n = 444) and IDH-wild type (n = 216) tumors. At the first and second interim analyses, there was an overall survival benefit seen with adjuvant temozolomide among patients with IDH-mutant tumors, but no benefit with concurrent temozolomide regardless of IDH mutation status.
At a median follow-up of 10.9 years, 499 events occurred in the intention-to-treat population. The hazard ratio (HR) for OS was 0.906 (95% confidence interval [CI], 0.760 to 1.082; P = .28) after concurrent temozolomide and 0.647 (95% CI, 0.541 to 0.773; P < .0001) after adjuvant temozolomide. Median OS was 1.7 years among patients with IDH–wild-type tumors and 8.5 years in patients with IDH-mutated tumors, with 45% of patients still alive. The HR for OS was 0.81 (95% CI, 0.63 to 1.04; P = .09) with concurrent temozolomide and 0.54 (95% CI, 0.42 to 0.69; P < .0001) with adjuvant temozolomide. No benefit was observed with both concurrent and adjuvant temozolomide (HR 0.92; 95% CI, 0.63 to 1.36; P = .69). Median OS for patients with IDH-mutant tumors who received temozolomide was 10.3 years. Median OS for patients who received adjuvant temozolomide was 12.5 years (95% CI, 9.4 to 15.0; P < .0001).
“Despite more follow-up, [concurrent temozolomide] did not improve OS regardless of IDH status,” concluded Dr Van Den Bent et al. “Standard of post-operative care in patients with high grade [IDH-mutant] astrocytoma should be [radiotherapy] followed by 12 cycles [of adjuvant temozolomide].
Source:
Van Den Bent M, Erridge S, Vogelbaum M, et al. Final clinical and molecular analysis of the EORTC randomized phase III intergroup CATNON trial on concurrent and adjuvant temozolomide in anaplastic glioma without 1p/19q codeletion: NCT00626990. Presented at 2025 ASCO Annual Meeting. May 30-June 3, 2025; Chicago, IL. Abstract 2002
