Regorafenib for Patients with Metastatic Colorectal Cancer Who Progressed After Standard Therapy: Results of the Large, Single-Arm, Open-Label Phase IIIb CONSIGN Study

Background In the phase III CORRECT trial, regorafenib significantly improved survival in treatment-refractory metastatic colorectal cancer (mCRC). The CONSIGN study was designed to further characterize regorafenib safety and allow patients access to regorafenib before market authorization. Methods This prospective, single-arm study enrolled patients in 25 countries at 186 sites. Patients with treatment-refractory mCRC and an Eastern Cooperative Oncology Group performance status (ECOG PS) <= 1 received regorafenib 160 mg once daily for the first 3 weeks of each 4-week cycle. The primary endpoint was safety. Progression-free survival (PFS) per investigator assessment was the only efficacy evaluation. Results In total, 2,872 patients were assigned to treatment and 2,864 were treated. Median age was 62 years, ECOG PS 0/1 was 47%/53%, and 74% had received at least three prior regimens for metastatic disease. Median treatment duration was three cycles. Treatment-emergent adverse events (TEAEs) led to dose reduction in 46% of patients. Regorafenib-related TEAEs led to treatment discontinuation in 9%. Grade 5 regorafenib-related TEAEs occurred in <1%. The most common grade >= 3 regorafenib-related TEAEs were hypertension (15%), hand-foot skin reaction (14%), fatigue (13%), diarrhea (5%), and hypophosphatemia (5%). Treatment-emergent grade 3-4 laboratory toxicities included alanine aminotransferase (6%), aspartate aminotransferase (7%), and bilirubin (13%). Ongoing monitoring identified one nonfatal case of regorafenib-related severe drug-induced liver injury per DILI Working Group criteria. Median PFS (95% confidence interval [CI]) was 2.7 months (2.6-2.7). Conclusion In CONSIGN, the frequency and severity of TEAEs were consistent with the known safety profile of regorafenib. PFS was similar to reports of phase III trials. : .