Treatment with trifluridine/tipiracil was safe and showed efficacy in patients with metastatic gastric cancer or gastroesophageal junction cancer regardless of their gastrectomy status, results of a preplanned analysis from the phase 3 randomized TAGS trial showed.
Trifluridine/tipiracil (FTD/TPI) was associated with significantly better overall survival (OS) and progression-free survival (PFS) than placebo in patients who had undergone gastrectomy, reported David H. Ilson, MD, PhD, of Memorial Sloan Kettering Cancer Center, New York, and colleagues.
“The benefits of FTD/TPI were especially noteworthy in the subpopulation of patients who had undergone gastrectomy, who tended to be more heavily pretreated and were less tolerant of therapy. The overall safety profile of the drug, including the incidence of severe AEs [adverse events] was similar among patients who had or had not undergone gastrectomy. No new safety concerns were reported in patients who had undergone gastrectomy,” they wrote in JAMA Oncology.
FTD/TPI is an oral drug combining the thymidine analogue trifluridine and tipiracil, an inhibitor of trifluridine degradation. The drug was approved by the FDA in 2015 under the trade name Lonsurf for the treatment of refractory metastatic colorectal cancer, and in 2019 for patients with metastatic gastric cancer or gastroesophageal junction cancer (mGC/GEJC) that had been treated with at least two lines of chemotherapy.
In a phase 2 study conducted in Japan with 29 patients with metastatic gastric cancer that had progressed after chemotherapy with fluoropyrimidine, platinum, taxanes, or irinotecan, FTD/TPI was associated with a median overall survival of 8.7 months and an investigator-assessed disease control rate of 65.5%,
As previously reported, in the randomized, controlled TAGS (TAS-102 Gastric Study), median overall survival, the primary endpoint, was 5.7 months for patients assigned to receive trifluridine/tipiracil, compared with 3.6 months for patients randomized to placebo.
The current study is a preplanned subgroup analysis from the TAGS trial. Of 507 randomized patients, 221 had undergone gastrectomy, and of this group 147 were randomized to FTD/TPI and 74 to placebo. The remaining 286 patients had not undergone gastrectomy, and of this group 190 were randomized to FTD/TPI and 96 to placebo.
Among patients who had undergone gastrectomy, the hazard ratio for OS of patients treated with FTD/TPI vs. placebo was 0.57 (95% confidence interval, 0.41-0.79), and the HR for PFS was 0.48 (95% CI, 0.35-0.65).
In the no-gastrectomy subgroup, the overall survival HR for patients who received FTD/TPI vs. placebo was 0.80 (95% CI , 0.60-1.06), and the HR for PFS was 0.65 (95% CI, 0.49-0.85).
Grade 3 or greater adverse events with FTD/TPI occurred in 84.1% of gastrectomy patients and 76.3% of no-gastrectomy patients. Grade 3 or greater neutropenia occurred in 44.1% and 26.3%, respectively; grade 3 or greater anemia in 21.4% vs. 17.4%; and grade 3 or greater leukopenia was observed in 14.5% vs. 5.3%.
Dose modifications because of adverse events were required for 64.8% of patients who had undergone gastrectomy, and in 53.2% of those who had not.
Treatment discontinuations because of AEs occurred in 10.3% and 14.7%, respectively.
The study was funded by Taiho Oncology and Taiho Pharmaceutical Company. Dr. Islon reported grants and advisory role support from Taiho and others. Multiple coauthors had similar disclosures.
SOURCE: Ilson DH et al. JAMA Oncol. 2019 Oct 10. doi: 10.1001/jamaoncol.2019.3531.