4368 - Safety of Tumor Treating Fields delivery to the torso: Meta analysis from TTFields clinical trials

Background

Tumor Treating Fields (TTFields) are a non-invasive, antimitotic therapy delivered to the tumor via transducer arrays applied to the skin at tumor site. The only TTFields-related adverse event (AE) reported in clinical trials was localized dermatitis beneath the arrays. The safety of TTFields has also been investigated in glioblastoma, non-small-cell lung cancer (NSCLC), mesothelioma, pancreatic and ovarian cancer. This meta-analysis reported AEs in clinical studies with TTFields torso delivery.

Methods

192 patients from 4 pilot studies were included in the analysis: EF-15 (n = 41, advanced NSCLC), PANOVA-2 (n = 40, advanced pancreatic adenocarcinoma), STELLAR (n = 80, malignant pleural mesothelioma) and INNOVATE (n = 31, recurrent ovarian carcinoma). The frequency of TTFields applied was 150 kHz in all except 200 kHz in the INNOVATE study. All patients received standard of care systemic chemotherapy for their disease in addition to TTFields. Severity and frequency, of AEs were reported using CTCAE Version 4 and CTCAE 3 in EF-15. AEs were reported as incidence by body system and MedDRA terms.

Results

The median age was 63 (range: 44-78), 73 (49-81), 67 (27-78) and 60 (45-77) for EF-15, PANOVA-2, STELLAR and INNOVATE, respectively. Patients had an ECOG score of 0-1, except for 7 patients in the EF-15 study with ECOG score of 2. Low grade gastrointestinal (GI) toxicities reported with an incidence ≥5%: constipation (16%), diarrhea (14%), nausea (27%), vomiting (13%). None of the GI toxicities was associated with TTFields, and the incidence of high-grade GI toxicities did not reach 10%. Low grade disorders such as asthenia (12%), fatigue (18%) and anorexia (2%) were common (<20%) but not associated with TTFields. Both low and high grade dyspnea (11% and 5%, respectively) were reported. The incidence of arrhythmia was <2%. 58% of the patients had dermatological AE. Low grade dermatitis was reported in 53% and high grade in only 6%. 9% of patients reported low grade pruritus.

Conclusions

This meta-analysis detected no new safety signals in clinical studies where TTFields were applied to the torso. The incidence of TTFields-related skin toxicity was similar to that reported in glioblastoma patients. The application of TTFields to the torso is safe.

Clinical trial identification

NCT: 01971281, 02244502; 02397928; 00749346.

Editorial acknowledgement

Legal entity responsible for the study

Novocure.

Funding

Novocure.

Disclosure

F. Grosso: Travel / Accommodation / Expenses: Novocure. G.L. Ceresoli: Travel / Accommodation / Expenses: Novocure. All other authors have declared no conflicts of interest.