Regorafenib in recurrent glioblastoma: Real-world outcomes from a Colombian cohort (REGOMA-COL).

Abstract

2078 Background: Therapeutic options for recurrent glioblastoma (GBM) remain limited, with historically poor outcomes following first progression. The phase II REGOMA trial demonstrated an overall survival benefit of regorafenib compared with lomustine, prompting its adoption in selected patients. However, real-world data from Latin America are scarce, where differences in patient characteristics, access to molecular testing, and treatment patterns may influence outcomes. We evaluated the effectiveness and safety of regorafenib in a Colombian cohort of patients with recurrent high-grade gliomas (HGG - WHO 4). Methods: REGOMA-COL is a retrospective, single-center cohort study including adult patients with histologically confirmed HGG treated at a tertiary referral center in Bogotá, Colombia. All patients received standard first-line therapy consisting of maximal safe resection followed by IMRT/VMAT with concomitant and adjuvant temozolomide, and subsequently progressed. Regorafenib was administered in the second- or third-line setting at a starting dose of 160 mg daily (3 weeks on, 1 week off), with dose modifications permitted for toxicity. Survival outcomes were estimated using the Kaplan–Meier method. Adverse events were graded according to CTCAE v5.0. Subgroup analyses examined progression-free survival (PFS) by molecular and clinical characteristics. Results: Twenty-six patients were included. The median age at diagnosis was 49.3 years, and 80.8% had an ECOG performance status of 1. Most tumors were IDH–wild type (84.6%), and MGMT promoter methylation was present in 38.5%. Regorafenib was administered as second-line therapy in 53.8% of patients and as third-line therapy in 57.7%. Median PFS from regorafenib initiation was 4.9 months (95% CI 3.9–5.7), and median OS from regorafenib was 11.3 months (95% CI 9.3–13.2) (Figure 1). Disease control rate (DCR) with regorafenib was achieved in 69.2% of patients. Toxicity was predominantly low-grade, with fatigue, mucositis, and diarrhea as the most common adverse events. Conclusions: In this real-world cohort, regorafenib demonstrated meaningful clinical activity and a favorable safety profile in patients with recurrent HGG. Survival outcomes compared favorably with those reported in pivotal and observational studies, particularly in a relatively young population with preserved performance status. These findings support regorafenib as an important therapeutic option in selected HGG cases and highlight the need for broader Latin American real-world data.