A phase II study of tarloxotinib (a hypoxia activated prodrug of a pan-erb tyrosine kinase inhibitor) in patients with recurrent or metastatic squamous cell carcinoma of the head and neck or skin.

Background: Tarloxotinib, a hypoxia-activated prodrug of an irreversible pan-ErbB tyrosine kinase inhibitor, represents a novel therapeutic which exploits the tumor-specific hypoxic environment as a mechanism for tumor-specific targeting. This study evaluated the safety and activity of tarloxotinib in recurrent or metastatic (R/M) cutaneous (CSCC) or head and neck squamous cell carcinoma (HNSCC).
Methods: This was a phase II two-stage multi-centre study for patients with R/M HNSCC or CSCC. All patients received tarloxotinib 150 mg/m2 on days 1,8,15 and 22 in a 28-day cycle. Stage 1 enrolled patients in three cohorts: p16-negative HNSCC, p16-positive oropharyngeal SCC, and CSCC. In order for a cohort to proceed to stage 2 a minimum response rate of 5% was required.
Results: 30 patients were enrolled: 23% were female with median age of 63.3 years. The median duration of follow-up was 20 weeks. The median progression-free survival was 2.0 months (95%CI 1.8-3.4) and median overall survival 5.7 months (95%CI 3.6-8.0). Treatment was well tolerated. The objective response rate was 3% with one patient with CSCC having a partial response.
Conclusions: Hypoxia-activated prodrugs represent a novel approach to cancer treatment, however, no clinically meaningful benefit for tarloxotinib in R/M HNSCC or CSCC was identified in this study.
Trial Registration Number: NCT02449681 (May 20, 2015).
(© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)