Fruquintinib: Mechanism of Action, Clinical, and Translational Science

Fruquintinib is a highly selective, oral inhibitor of all three vascular endothelial growth factor receptors (-1, -2, and -3) that was approved, including in China, the United States, and the European Union, for the treatment of previously treated metastatic colorectal cancer (mCRC). The efficacy of fruquintinib for mCRC has been consistently demonstrated in randomized, double-blind, Phase 3 clinical studies, including FRESCO (NCT02314819), which enrolled patients in China, and FRESCO-2 (NCT04322539), which enrolled patients across 14 countries in North America, Europe, Asia, and Australia. In both studies, patients were randomized 2:1 to receive oral fruquintinib 5 mg or a matching placebo once daily, 3 weeks on, 1 week off, in 28-day cycles, plus best supportive care, until progression or unacceptable toxicity. Both FRESCO and FRESCO-2 met their primary endpoints, demonstrating significant improvements in overall survival (OS) with fruquintinib versus placebo: in FRESCO (fruquintinib: n = 278; placebo: n = 138), median OS was 9.3 with fruquintinib versus 6.6 months with placebo (hazard ratio [HR], 0.65; 95% confidence interval [CI], 0.51-0.83; p < 0.001); in FRESCO-2 (fruquintinib: n = 461; placebo: n = 230), median OS was 7.4 with fruquintinib versus 4.8 months with placebo (HR, 0.66; 95% CI, 0.55-0.80; p < 0.001). The most common any-grade treatment-emergent adverse events with fruquintinib (incidence ≥ 20% in either study, excluding laboratory abnormalities) were hypertension, palmar-plantar erythrodysesthesia, proteinuria, dysphonia, diarrhea, asthenia, decreased appetite, hypothyroidism, and fatigue. This mini-review summarizes the mechanism of action, pharmacokinetics, key clinical trials, and clinical efficacy and safety data for fruquintinib.