gms | German Medical Science

Objective: Glioblastoma (GBM) is the most aggressive brain tumor in adults, accounting for approximately 15% of all primary brain tumors with a substantial proportion of patients at the time of diagnosis aged 65 years or older. Tumor Treating Fields (TTFields) are an established modality for GBM treatment administered through the portable Optune system. The EF-14 phase 3 trial previously demonstrated the efficacy of Optune in newly diagnosed GBM (ndGBM). TTFields plus temozolomide significantly improved survival in all patient subgroups compared to temozolomide alone, including elderly patients ≥ 65 years (median OS: 17.1 vs 13.7 months). No treatment limiting systemic adverse events were observed in the EF-11 trial for recurrent GBM (rGBM) or in the EF-14 trial for ndGBM. Here, we report post-marketing surveillance data from elderly patients (≥ 65 years) treated with Optune.

Methods: This analysis of the post-marketing surveillance safety data compared the adverse event (AE) profile of patients treated with TTFields in two age groups: elderly patients ≥65 years of age as compared to adult patients between 18 and 65 years of age. Global post-market surveillance data (2011 to April 2018) for all patients with TTFields prescription were analyzed for AEs based on the MedDRA (Medical Dictionary for Regulatory Activities) body system (system organ class) preferred terms.

Results: A total of 8025 patients were treated with TTFields (ndGBM 46.1%, rGBM 46.2%, other 7.7%). Amongst those, 2574 patients (32.1%) were aged ≥65 at the time of Optune treatment. 46% of these elderly patients reported ≥1 adverse event. The most prevalent AE was skin reaction, which occurred in 28% of patients. Similarly, 47% of patients ≥18 and <65 years of age (N=5421) experienced at least 1 adverse event and 27% developed skin reaction. Other AEs included general clinical decline (21%), nervous system disorders (12%) and injury (7%), which was fairly equally distributed between both age groups.

Conclusion: This retrospective analysis demonstrates that TTFields are commonly used in elderly patients ≥65 years of age. The AE profile in this group of elderly patients is similar to that of patients younger than 65. The most common AE registered was skin reaction, which is in line with the results of the phase 3 EF-11 trial for rGBM and the EF-14 trial for ndGBM patients. This analysis identifies no additional safety signals on the use of TTFields in the elderly population and underlines the safety profile of Optune.