SUMMARY: The FDA on September 22, 2015 approved LONSURF® (Trifluridine/Tipiracil) for the treatment of patients with metastatic ColoRectal Cancer (CRC), who have been previously treated with Fluoropyrimidine, Oxaliplatin and Irinotecan-based chemotherapy, an anti-VEGF biological therapy and if RAS wild-type, an anti-EGFR therapy. The American Cancer Society estimates that approximately 133,000 new cases of ColoRectal Cancer (CRC) will be diagnosed in the United States in 2015 and close to 50,000 are expected to die of the disease. Approximately 15-25% of the patients with CRC present with metastatic disease at the time of diagnosis (synchronous metastases) and 50-60% of the patients with CRC will develop metastatic disease during the course of their illness. Patients with metastatic CRC, whose disease has progressed after treatment with standard therapies, have limited therapeutic options available, to treat their disease.
LONSURF® is a combination of two agents – a novel oral nucleoside, Trifluridine and a thymidine phosphorylase inhibitor, Tipiracil hydrochloride. This combination has a unique mechanism of action. Trifluridine, the active ingredient of LONSURF® incorporates into DNA resulting in DNA damage. Degradation of Trifluridine which occurs when taken orally is prevented by Tipiracil hydrochloride.
The RECOURSE study is a pivotal, global, phase III trial, in which 800 patients with metastatic ColoRectal Cancer, refractory to all standard therapies were randomly assigned in a 2:1 ratio to receive either LONSURF® (N=534) or placebo (N=266). Patients received LONSURF® 35mg/m2 or matching placebo orally, twice daily after meals, on Days 1-5 and 8-12 of each 28 day cycle. Treatment was continued until disease progression or unacceptable toxicity. Eligible patients had metastatic ColoRectal Cancer (mCRC), previously treated with chemotherapy and biological therapy, which included Fluoropyrimidine, Oxaliplatin and Irinotecan-based chemotherapy, an anti-VEGF biological therapy and if RAS wild-type, an anti-EGFR therapy. The primary endpoint of this study was overall survival and the secondary endpoint was progression-free survival.
It was noted that LONSURF® significantly improved Overall Survival compared to placebo (7.1 months vs 5.3 months; HR=0.68; P<0.001), with a 32% reduction in the risk of death. LONSURF® also significantly improved Progression Free Survival compared to placebo (HR = 0.47; P<0.001). The most common grade 3 or more adverse events were leukopenia (21%), anemia (18%) and febrile neutropenia (4%), noted in patients receiving LONSURF®. The authors concluded that LONSURF® significantly improved Overall Survival in patients with refractory metastatic ColoRectal Cancer, providing a novel oral therapeutic option for this patient group. Randomized Trial of TAS-102 for Refractory Metastatic Colorectal Cancer. Mayer RJ, Van Cutsem E, Falcone A, et al. N Engl J Med 2015; 372:1909-1919