Purpose: Regorafenib is an oral multi-kinase inhibitor that offers an OS benefit to patients with mCRC refractory to standard therapy (Grothey et al., in Lancet 381:303-312, 2013), but comes with potential significant toxicities including grade 3 hand-foot skin reaction (HFSR). The pathogenesis of regorafenib-induced HFSR is not well established, but may be related to alterations in the capillary endothelium. We hypothesized that perindopril, an angiotensin-converting enzyme (ACE) inhibitor, indicated for the treatment of hypertension (Ceconi et al., in Cardiovasc Res 73:237-246, 2007), and which plays a role in preventing endothelial dysfunction, may help to prevent or reduce the severity of regorafenib-induced HFSR.
Patients and methods: In this single-center phase II open-label trial, patients with refractory mCRC were treated with both regorafenib (160 mg/day) and perindopril (4 mg/day) for 21 days per 28-day cycle. The primary end point was to assess the proportion of patients with any grade HFSR toxicity. Secondary end points included time to development of worst (grade 3) HFSR, reduction of all grades of hypertension and all grade toxicities, as well as progression-free survival. All toxicities were evaluated using CTCAE v4.03.
Results: A planned interim analysis was performed after ten evaluable patients had completed their first cycle of study treatment. As 50% (5/10) experienced grade 3 HFSR, enrolment was stopped as the addition of perindopril did not lead to a reduced level of HFSR compared with regorafenib alone. Other grade 3 toxicities included hypertension (16.7%) and increased AST (16.7%).
Conclusion: The addition of an ACE inhibitor perindopril to regorafenib did not reduce HFSR incidence or severity in patients with refractory mCRC.
Keywords: ACE inhibitor; Colorectal cancer; HFSR; Perindopril; Regorafenib.