Triple Compound Shows Promise in Patients With Colorectal and Head-and-Neck Cancers
Phase III data presented at ASCO meeting (June 6)
Positive results from three phase III trials of the cancer drug TS-1 (Taiho Pharmaceutical Co.) were presented at the 49th Annual Meeting of the American Society of Clinical Oncology (ASCO), held in Chicago, Illinois, from May 31 to June 4. All of the studies were conducted in Japan.
In the ACTS-CC trial, TS-1 was compared with standard-treatment uracil/tegafor and leucovorin (UFT/LV) in patients with resected stage III colon cancer.
Three-year disease-free survival (DFS) was 75.5% in the TS-1 group and 72.5% in the UFT/LV group, demonstrating the noninferiority of TS-1 on this endpoint (hazard ratio [HR] = 0.85; noninferiority test, P < 0.0001).
In the SOFT trial, TS-1/oxaliplatin (SOX) + bevacizumab (Bev) was compared with standard-treatment 5-fluorouracil (5-FU)/leucovorin (LV)/oxaliplatin (FOLFOX) + Bev in patients with metastatic colorectal cancer.
Median progression-free survival (PFS) for SOX + Bev was 11.7 months compared with 11.5 months for FOLFOX + Bev, which demonstrated the noninferiority of SOX + Bev in comparison with FOLFOX + Bev on this endpoint (HR = 1.043; non-inferiority test, P = 0.0139).
In the ACTS-HNC trial, TS-1 was compared with UFT in patients who underwent curative treatment for squamous cell carcinoma of the head and neck.
Three-year DFS was 64.1% in the TS-1 group and 60.0% in the UFT group, which did not demonstrate the superiority of TS-1 on this endpoint (HR = 0.87; P = 0.34). However, the 3-year survival rate in the TS-1 group was 82.9% compared with 75.8% in the UFT group, which indicated a statistically significant advantage for TS-1 (HR = 0.64; P = 0.02).
A member of the fluoropyrimidine class of chemotherapeutic agents, TS-1 is a combination of three pharmacological compounds: tegafur, an antimetabolite agent that, after absorption, is converted into 5-FU; gimeracil, which decreases the degradation of 5-FU in the liver; and oteracil, which decreases 5-FU phosphorylation in the gastrointestinal tract. Developed as a gastric cancer treatment, TS-1 was first approved in Japan in 1999. The drug currently has six cancer indications in Japan. It is also used to treat gastric cancer in 15 European countries and in seven countries in Asia.
Source: Taiho Pharmaceutical Co.; June 6, 2013.