Telix’s TLX101 Improves Survival In Recurrent High-Grade Glioma, Supporting Earlier Findings

Telix Pharmaceuticals has reported encouraging preliminary results from its Phase 2 IPAX-Linz study, which investigates TLX101 (¹³¹I-iodofalan) for treating recurrent high-grade glioma (HGG), including glioblastoma. In collaboration with investigators, the trial evaluated the safety, tolerability, and early efficacy of TLX101 in combination with external beam radiation therapy (EBRT) in patients experiencing their first or second tumour recurrence. The treatment was well tolerated, with no serious adverse events observed during the trial. 

Professor Josef Pichler, Kepler University Hospital, Austria, Principal Investigator in the IPAX-Linz, IPAX-1, and IPAX-2 studies, commented, “These preliminary results in relapsed patients showed that TLX101 treatment was very well tolerated, with no serious adverse events, at a higher dose than in previous studies. Early efficacy from IPAX-1 was corroborated despite the poor prognostic parameters with MGMT unmethylated tumours and multiple relapses before commencing experimental therapy in this IPAX-Linz study. TLX101 continues showing significant potential to improve outcomes for patients with high-grade glioma. These results also potentially support higher therapeutic doses in subsequent prospective controlled studies.”

The study showed a median overall survival (OS) of 12.4 months from TLX101 treatment initiation or 32.2 months from initial diagnosis, aligning well with outcomes from the earlier IPAX-1 study, which recorded a median OS of 13 months from TLX101 initiation. These results compare favourably against the 9.9 months median survival benchmark for patients treated with EBRT alone. The study enrolled eight patients, using adaptive dosing up to 4 GBq before and 2 GBq after second-line EBRT. Inclusion was based on advanced imaging using TLX101-CDx (Pixclara®) to confirm increased amino acid uptake, indicative of tumour activity. 

Dr. David Cade, Chief Medical Officer at Telix, said, “These are encouraging results, offering new options for patients with historically poor outcomes. We are grateful to Dr. Pichler and his team for building on the IPAX-1 study in a more advanced and complex study cohort representing a real-world patient population.”

Importantly, five of the eight patients had MGMT-unmethylated tumours, a subgroup known for poor prognosis and resistance to standard therapies, further highlighting the potential impact of TLX101. Dr Pichler will present the full preliminary findings at Vienna's Nuclear Medicine and Neurooncology (NMN) Symposium on May 9–10, 2025.