Abstract 3000
Background
High deoxyuridine triphosphatase (dUTPase) in tumor tissue, as a gatekeeper enzyme for 5-fluorouracil (5-FU), is associated with 5-FU resistance. TAS-114 is an oral dUTPase inhibitor which enhance antitumor activity with 5-FU or fluoropyrimidines. Phase I study of TAS-114 in combination with S-1 showed its tolerability and preliminary antitumor signals for patients (pts) with non-small cell lung cancer and advanced gastric cancer (AGC). This phase II study has been conducted to evaluate efficacy and safety of TAS-114 and S-1 combination in pts with AGC.
Methods
The main eligibility criteria is pts with AGC after two or more previous chemotherapy regimens containing fluoropyrimidines, platinum agents, and taxanes or irinotecan. The primary endpoint is objective response rate (ORR) by investigators’ judgement. Using Simon’s optimal two-stage design, 29 pts were required, with one-sided a = 5% and power=80%. The threshold and expected ORRs were 5% and 25%. Protein expression levels of dUTPase and BRCA1 in tumor samples were determined by immunohistochemistry.
Results
The accrual was terminated in June 2018. Of all 20 enrolled pts, the ORR and disease control rate were 5.0% (95% confidence interval [CI], 0.1-24.9%) and 70.0% (95% CI, 45.7-88.1%), respectively. The median progression-free survival (PFS) and overall survival were 2.4 months (95% CI, 1.2-3.3 months) and 7.1 months (95% CI, 5.2-9.4 months), respectively. The median PFS in the groups with high and low dUTPase protein expression in the cytoplasm was 2.8 months (95% CI, 1.4–3.9) and 1.6 months (95% CI, 0.6–2.4), respectively (hazard ratio, 0.40 [95% CI, 0.16–1.04], P = 0.047). Grade 3 or higher treatment-related adverse events were anemia (20%), leucopenia (15%), neutropenia (10%), rash (10%), thrombocytopenia (5%), and Iymphopenia (5%).
Conclusions
TAS-114 with S-1 showed modest antitumor activity with acceptable safety profiles for heavily pretreated pts with AGC.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Taiho.
Disclosure
D. Takahari: Research grant / Funding (self): Taiho Pharmaceutical Co; Research grant / Funding (self): Ono Pharmaceutical Co; Honoraria (self): Eli Lilly Japan; Honoraria (self): Bristol-Myers Squibb; Honoraria (self): Yakult Honsha Co; Honoraria (self): Chugai Pharmaceutical Co., Ltd. A. Kawazoe: Honoraria (self), Research grant / Funding (institution): Taiho. K. Shitara: Honoraria (self): Novartis; Honoraria (self): AbbVie; Honoraria (self): Yakult; Advisory / Consultancy: Astellas Pharma; Advisory / Consultancy: Lilly; Advisory / Consultancy: Bristol-Myers Squibb; Advisory / Consultancy: Takeda; Advisory / Consultancy: Pfizer; Advisory / Consultancy: Ono Pharmaceutical; Advisory / Consultancy: MSD; Research grant / Funding (institution): Astellas Pharma; Research grant / Funding (self): Lilly; Research grant / Funding (institution): Ono Pharmaceutical; Research grant / Funding (institution): Dainippon Sumitomo Pharma; Research grant / Funding (institution): Daiichi Sankyo; Research grant / Funding (institution): Taiho Pharmaceutical; Research grant / Funding (institution): Chugai Pharma; Research grant / Funding (institution): MSD; Research grant / Funding (institution): Medi Science. All other authors have declared no conflicts of interest.
Resources from the same session
3059 - Intraoperative chemotherapy with 5-FU for colorectal cancer patients receiving curative resection (IOCCRC): A randomized, multicenter, prospective, phase III trial
Presenter: Rongxin Zhang
Session: Poster Display session 2
Resources:
Abstract
3082 - Prognostic and predictive role of body mass index (BMI) in metastatic colorectal cancer (mCRC): a pooled analisys of TRIBE and TRIBE-2 studies by GONO
Presenter: Emanuela Dell'Aquila
Session: Poster Display session 2
Resources:
Abstract
3618 - Drug holidays and overall survival in patients treated for metastatic colorectal cancer
Presenter: Silvio Ken Garattini
Session: Poster Display session 2
Resources:
Abstract
6111 - Quality of life during 1st-line FOLFOXIRI+/- panitumumab in RAS wild-type metastatic colorectal cancer: Results from the randomized VOLFI trial (AIO KRK-0109)
Presenter: Michael Geissler
Session: Poster Display session 2
Resources:
Abstract
1042 - A biomarker combination indicating resistance to FOLFOX plus bevacizumab in metastastic colorectal cancer : results of phase I of the PERMAD trial
Presenter: Thomas Seufferlein
Session: Poster Display session 2
Resources:
Abstract
3291 - Microsatellite Instability (MSI) status and prognosis in colorectal cancer: meta-analysis
Presenter: James Toh
Session: Poster Display session 2
Resources:
Abstract
2046 - Choosing the right strategy based on individualized treatment effect predictions: Combination versus sequential chemotherapy in patients with metastatic colorectal cancer.
Presenter: Miriam Koopman
Session: Poster Display session 2
Resources:
Abstract
2589 - Noninferiority on overall survival of every-2-weeks vs weekly schedule of cetuximab for first-line treatment of RAS wild-type metastatic colorectal cancer
Presenter: Stefan Kasper
Session: Poster Display session 2
Resources:
Abstract
4944 - POLAF study: Efficacy and safety of FOLFIRI/aflibercept in a phase II trial in patients with metastatic colorectal cancer: Results of plasmatic prognostic and predictive markers
Presenter: Maria Elena Elez Fernandez
Session: Poster Display session 2
Resources:
Abstract
2042 - The accuracy of the clinical PCI score in patients with peritoneal carcinomatosis of colorectal cancer
Presenter: Nadine De Boer
Session: Poster Display session 2
Resources:
Abstract