Adjuvant chemotherapy for gastric cancer with S-1, an oral fluoropyrimidine

BACKGROUND

Advanced gastric cancer can respond to S-1, an oral fluoropyrimidine. We tested S-1 as adjuvant chemotherapy in patients with curatively resected gastric cancer.

METHODS

Patients in Japan with stage II or III gastric cancer who underwent gastrectomy with extended (D2) lymph-node dissection were randomly assigned to undergo surgery followed by adjuvant therapy with S-1 or to undergo surgery only. In the S-1 group, administration of S-1 was started within 6 weeks after surgery and continued for 1 year. The treatment regimen consisted of 6-week cycles in which, in principle, 80 mg of oral S-1 per square meter of body-surface area per day was given for 4 weeks and no chemotherapy was given for the following 2 weeks. The primary end point was overall survival.

RESULTS

We randomly assigned 529 patients to the S-1 group and 530 patients to the surgery-only group between October 2001 and December 2004. The trial was stopped on the recommendation of the independent data and safety monitoring committee, because the first interim analysis, performed 1 year after enrollment was completed, showed that the S-1 group had a higher rate of overall survival than the surgery-only group (P=0.002). Analysis of follow-up data showed that the 3-year overall survival rate was 80.1% in the S-1 group and 70.1% in the surgery-only group. The hazard ratio for death in the S-1 group, as compared with the surgery-only group, was 0.68 (95% confidence interval, 0.52 to 0.87; P=0.003). Adverse events of grade 3 or grade 4 (defined according to the Common Toxicity Criteria of the National Cancer Institute) that were relatively common in the S-1 group were anorexia (6.0%), nausea (3.7%), and diarrhea (3.1%).

CONCLUSIONS

S-1 is an effective adjuvant treatment for East Asian patients who have undergone a D2 dissection for locally advanced gastric cancer. (ClinicalTrials.gov number, NCT00152217 [ClinicalTrials.gov].).

Phase III study comparing oxaliplatin plus S-1 with cisplatin plus S-1 in chemotherapy-naïve patients with advanced gastric cancer

BACKGROUND

We evaluated the efficacy and safety of S-1 plus oxaliplatin (SOX) as an alternative to cisplatin plus S-1 (CS) in first-line chemotherapy for advanced gastric cancer (AGC).

PATIENTS AND METHODS

In this randomized, open-label, multicenter phase III study, patients were randomly assigned to receive SOX (80-120 mg/day S-1 for 2 weeks with 100 mg/m(2) oxaliplatin on day 1, every 3 weeks) or CS (S-1 for 3 weeks with 60 mg/m(2) cisplatin on day 8, every 5 weeks). The primary end points were noninferiority in progression-free survival (PFS) and relative efficacy in overall survival (OS) for SOX using adjusted hazard ratios (HRs) with stratification factors; performance status and unresectable or recurrent (+adjuvant chemotherapy) disease.

RESULTS

Overall, 685 patients were randomized from January 2010 to October 2011. In per-protocol population, SOX (n = 318) was noninferior to CS (n = 324) in PFS [median, 5.5 versus 5.4 months; HR 1.004, 95% confidence interval (CI) 0.840-1.199; predefined noninferiority margin 1.30]. The median OS for SOX and CS were 14.1 and 13.1 months, respectively (HR 0.958 with 95% CI 0.803-1.142). In the intention-to-treat population (SOX, n = 339; CS, n = 337), the HRs in PFS and OS were 0.979 (95% CI 0.821-1.167) and 0.934 (95% CI 0.786-1.108), respectively. The most common ≥grade 3 adverse events (SOX versus CS) were neutropenia (19.5% versus 41.8%), anemia (15.1% versus 32.5%), hyponatremia (4.4% versus 13.4%), febrile neutropenia (0.9% versus 6.9%), and sensory neuropathy (4.7% versus 0%).

CONCLUSION

SOX is as effective as CS for AGC with favorable safety profile, therefore SOX can replace CS.

CLINICAL TRIAL NUMBER

JapicCTI-101021.

Late phase II study of novel oral fluoropyrimidine anticancer drug S-1 (1 M tegafur-0.4 M gimestat-1 M otastat potassium) in advanced gastric cancer patients

S-1 is a novel oral anticancer drug, composed of tegafur (FT), gimestat (CDHP) and otastat potassium (Oxo) in a molar ratio of 1:0.4:1, based on the biochemical modulation of 5-fluorouracil (5-FU). CDHP inhibits dihydropyrimidine dehydrogenase (DPD), an enzyme which degrades 5-FU, and maintains prolonged 5-FU concentrations in the blood and tumours. Oxo is distributed in the gastrointestinal tract at a high concentration after oral administration and alleviates gastrointestinal toxicity due to 5-FU. S-1 improves the tumour-selective toxicity of 5-FU by the actions of two modulators, CDHP and Oxo. We conducted a late phase II clinical trial of S-1 as an open trial in patients with advanced gastric cancer, to confirm its antitumour effect and adverse reactions. 51 patients with advanced gastric cancer were enrolled in the trial. S-1 was administered orally twice daily after meals, at a standard dose of 80 mg/m2/day. One course consisted of consecutive administration for 28 days and 14 days' rest. Administration was repeated over four courses. A complete response was obtained in 1 patient and partial responses in 24 patients, producing a response rate of 49% (25/51) (95% confidence interval (CI) 35.9-62.3%). The incidence of adverse reactions was 78% (40/51) and that of adverse reactions of grades 3 and 4 was 20%. Adverse reactions of grades 3 and 4 included a decrease in the haematocrit, leucopenia, granulocytopenia, diarrhoea, malaise and proteinuria. No serious unexpected adverse reactions were observed. In conclusion, S-1 was effective and well tolerated in patients with advanced gastric cancer.

Phase II study of S-1, a novel oral derivative of 5-fluorouracil, in advanced gastric cancer. For the S-1 Cooperative Gastric Cancer Study Group

PURPOSE

To assess the efficacy and safety of S-1, a novel oral fluoropyrimidine derivative, we conducted a multicenter late phase II study in patients with advanced gastric cancer.

PATIENTS AND METHODS

Fifty-one patients who had received no previous chemotherapy were enrolled. Fifty patients were eligible for efficacy and safety analyses. The overall response was evaluated for the 43 patients who had metastatic lesions. S-1 was administered orally after breakfast and dinner for 28 days, followed by a 14-day break. The dosages were assigned according to the patients' body surface area (BSA): BSA <1.25 m(2), 40 mg; 1.25-1.5 m(2), 50 mg, and BSA > or =1.5 m(2), 60 mg, twice daily.

RESULTS

The overall response to treatment was evaluated as partial response in 19 of the 43 patients (44%; 95% confidence interval 30-59%). The median survival time in all patients was 207 days with 1- and 2-year survival rates of 36.0 and 14.0%, respectively. Grade 3 adverse reactions included decreased hemoglobin values in 2 patients, leukopenia, neutropenia and diarrhea in 1 patient each. No other grade 4 or unexpected adverse reactions were seen.

CONCLUSIONS

S-1 is effective against advanced gastric cancer. This oral treatment is suitable for outpatients because of its mild toxicity. Further therapeutic benefits are likely to be obtained by combining S-1 with other chemotherapeutic agents.

A phase I/II study of gemcitabine-based chemotherapy plus curcumin for patients with gemcitabine-resistant pancreatic cancer

PURPOSE

Curcumin, a plant-derived natural polyphenol, could be a promising anti-cancer drug and shows synergic effects with cytotoxic agents. We evaluated the safety and feasibility of combination therapy using curcumin with gemcitabine-based chemotherapy.

METHODS

Gemcitabine-resistant patients with pancreatic cancer received 8 g oral curcumin daily in combination with gemcitabine-based chemotherapy. The primary endpoint was safety for phase I and feasibility of oral curcumin for phase II study.

RESULTS

Twenty-one patients were enrolled. No dose-limiting toxicities were observed in the phase I study and oral curcumin 8 g/day was selected as the recommended dose for the phase II study. No patients were withdrawn from this study because of the intolerability of curcumin, which met the primary endpoint of the phase II study, and the median compliance rate of oral curcumin was 100% (Range 79-100%). Median survival time after initiation of curcumin was 161 days (95% confidence interval 109-223 days) and 1-year survival rate was 19% (4.4-41.4%). Plasma curcumin levels ranged from 29 to 412 ng/ml in five patients tested.

CONCLUSIONS

Combination therapy using 8 g oral curcumin daily with gemcitabine-based chemotherapy was safe and feasible in patients with pancreatic cancer and warrants further investigation into its efficacy.

Combination gemcitabine plus S-1 versus gemcitabine plus cisplatin for advanced/recurrent biliary tract cancer: the FUGA-BT (JCOG1113) randomized phase III clinical trial

BACKGROUND

Gemcitabine plus cisplatin (GC) is the standard treatment of advanced biliary tract cancer (BTC); however, it causes nausea, vomiting, and anorexia, and requires hydration. Gemcitabine plus S-1 (GS) reportedly has equal to, or better, efficacy and an acceptable toxicity profile. We aimed to confirm the non-inferiority of GS to GC for patients with advanced/recurrent BTC in terms of overall survival (OS).

PATIENTS AND METHODS

We undertook a phase III randomized trial in 33 institutions in Japan. Eligibility criteria included chemotherapy-naïve patients with recurrent or unresectable BTC, an Eastern Cooperative Oncology Group Performance Status of 0 - 1, and adequate organ function. The calculated sample size was 350 with a one-sided α of 5%, a power of 80%, and non-inferiority margin hazard ratio (HR) of 1.155. The primary end point was OS, while the secondary end points included progression-free survival (PFS), response rate (RR), adverse events (AEs), and clinically significant AEs defined as grade ≥2 fatigue, anorexia, nausea, vomiting, oral mucositis, or diarrhea.

RESULTS

Between May 2013 and March 2016, 354 patients were enrolled. GS was found to be non-inferior to GC [median OS: 13.4 months with GC and 15.1 months with GS, HR, 0.945; 90% confidence interval (CI), 0.78-1.15; P = 0.046 for non-inferiority]. The median PFS was 5.8 months with GC and 6.8 months with GS (HR 0.86; 95% CI 0.70-1.07). The RR was 32.4% with GC and 29.8% with GS. Both treatments were generally well-tolerated. Clinically significant AEs were observed in 35.1% of patients in the GC arm and 29.9% in the GS arm.

CONCLUSIONS

GS, which does not require hydration, should be considered a new, convenient standard of care option for patients with advanced/recurrent BTC.

CLINICAL TRIAL NUMBER

This trial has been registered with the UMIN Clinical Trials Registry (http://www.umin.ac.jp/ctr/index.htm), number UMIN000010667.

Phase II study of S-1, a novel oral fluorophyrimidine derivative, in patients with metastatic colorectal carcinoma. S-1 Cooperative Colorectal Carcinoma Study Group

This study set out to evaluate, in patients with metastatic colorectal carcinoma, the efficacy and toxicity of S-1, which contains tegafur, 5-chloro-2,4-dihydroxypyridine (CDHP) and potassium oxonate, based on a biochemical modulation of 5-fluorouracil (5-FU) targeted at inhibition of dihydropyrimidine dehydrogenase (DPD). Sixty-three patients with measurable metastatic colorectal carcinoma were enrolled into the study. None of the patients had received prior chemotherapy except for adjuvant setting. S-1 was administered orally twice daily at a standard dose of 80 mg m(-2) day(-1) for 28 days followed by a 14-day rest. This agent is continued until disease progression, unaccepted toxicity, or patient refusal. Twenty-two (35%) of the 62 eligible patients achieved PR with a 95% confidence interval of 25-48%. Five of the 10 patients with a history of adjuvant chemotherapy achieved partial remission. The median survival time was 12 months. Major adverse reactions included myelosuppressive and gastrointestinal toxicities, though their incidence of grade 3 or 4 being 13% in neutropenia and less than 10% in the others. None of the 53 patients treated as outpatients required hospitalization due to adverse reactions: These results suggest that S-1 achieves similar responses to those of infusional 5-FU plus leucovorin and shows the potential of another biochemical modulation with easily manageable toxicity.

Phase II study of docetaxel and S-1 combination therapy for advanced or recurrent gastric cancer

PURPOSE

To evaluate the efficacy and toxicity of docetaxel in combination with a novel oral 5-fluorouracil analogue S-1 for patients with advanced or recurrent gastric cancer.

EXPERIMENTAL DESIGN

Patients with advanced or recurrent adenocarcinoma of the stomach and up to one previous chemotherapy regimen were treated with i.v. docetaxel 40 mg/m2 on day 1 and oral S-1 80 mg/m2/d on days 1 to 14 every 3 weeks.

RESULTS

Forty-eight patients (median age, 65 years; range, 25-75 years) received a total of 272 treatment cycles (median, 4; range, 1-17). No complete responses and 27 partial responses were observed for an overall response rate of 56.3% [95% confidence interval (95% CI), 38-66%]. Eighteen patients (37.5%) had stable disease and three patients (6.3%) had progressive disease as best response. The tumor control rate (complete response + partial response + stable disease) was 93.8% (95% CI, 83-98%). Median overall survival was 14.3 months (95% CI, 10.7-20.3 months) and median time to tumor progression was 7.3 months (95% CI, 4.3-10.0 months). The most common grade 3 to 4 hematologic toxicities were neutropenia (58.3%), leukopenia (41.7%), febrile neutropenia (8.3%), and anemia (8.3%). The most common grade 3 nonhematologic toxicities included anorexia (14.6%), stomatitis (8.3%), and nausea (6.3%). No grade 4 nonhematologic toxicities were reported and all treatment-related toxicities were resolved.

CONCLUSION

Docetaxel/S-1 combination is highly active and well tolerated in advanced or recurrent gastric cancer. Further investigation in randomized studies is warranted.

A late phase II study of S-1 for metastatic pancreatic cancer

This study evaluated the antitumor effect and safety of S-1, an oral fluoropyrimidine derivative, in patients with metastatic pancreatic cancer. Chemo-naive patients with pancreatic adenocarcinoma, and measurable metastatic lesions were enrolled. S-1 was administered orally twice daily after meals at a dose of 80, 100, or 120 mg/day for body surface areas (BSAs) of less than 1.25 m(2), between 1.25 m(2) and less than 1.5, or 1.5 m(2) or greater, respectively, for 28 consecutive days, followed by a 14-day rest. Fifteen (37.5%) of 40 patients responded to treatment, including 1 complete response and 14 partial responses. The median time to progression and the overall survival time were 3.7 months (95% confidence interval, 2.2-5.6 months) and 9.2 months (95% confidence interval, 7.5-10.8 months), respectively. The major adverse events were anorexia, fatigue, hemoglobin reduction, nausea and pigmentation change, although most were tolerable and reversible. Although disseminated intravascular coagulation occurred in two patients, the condition resolved with anticoagulant therapy. S-1 is an effective and well-tolerated drug. The effectiveness of this drug should be confirmed in a phase III study.

An early phase II study of oral S-1, a newly developed 5-fluorouracil derivative for advanced and recurrent gastrointestinal cancers. The S-1 Gastrointestinal Cancer Study Group

5-Fluorouracil (5-FU) or a 5-FU derivative 1-(2-tetrahydrofuryl)-5-fluorouracil (FT) has been widely prescribed for patients with gastrointestinal cancer. However, the phosphorylation of 5-FU in the digestive tract causes gastrointestinal toxicities. 5-FU is also rapidly degraded to alpha-fluoro-beta-alanine after contact with dihydropyrimidine dehydrogenase (DPDase) which is mainly present in the liver. Therefore, to overcome these metabolic events, S-1, an antitumor agent was developed, based on the biochemical modulation of FT by 5-chloro-2,4-dihydroxypyridine (CDHP) and potassium oxonate (Oxo), in a molar ratio of 1:0.4:1. The antineoplastic effect of S-1, was examined in Japanese patients with advanced gastric (G) or colorectal (C) cancer in a multicenter early phase II study involving 24 centers throughout Japan. The patients were prescribed a minimum of 2 courses of S-1 orally, with each course consisting of 75 or 50 mg (in terms of FT) twice a day for 28 days followed by withdrawal for 2 weeks. Thirty-one patients with G and 31 C were entered into this study. The clinical response and extent of toxicity were evaluated in G 28 and C 30 cases, respectively. Nine (32.1%) G patients and 14 (46.7%) C patients had been treated previously with other anticancer drugs. In G patients, there was a 53.6% (15/28) and in C patients a 16.7% (5/30) response rate (90% confidence interval G 38.4-68.1% and C 8.4-30.5%) with 15 (53.6%) (G) and 5 (16.7%) (C) partial responses (PR), and these responses persisted for 79 days (G) and 120 days (C) (median value). In particular, the response rate for the primary lesion was 27.8% (5/18) (G) and 33.3% (1/3) (C). No change (NC) in the disease was observed in 4 (14.3%) (G) and 13 (43.3%) (C) patients, and in 6 (21. 4%) (G) and 7 (23.3%) (C) the disease progressed (PD). At the time of analysis, the median survival was 298 days (G) and 358 days (C). Major adverse effects consisted of gastrointestinal symptoms and myelosuppression while toxicities of grade 3 or more occurred in 35. 7% (10/28) (G) and 33.3% (10/30) (C). Based on these data, S-1 is considered to have positive effects in patients with advanced gastrointestinal cancer.

Comparison of the pharmacokinetics and pharmacodynamics of S-1 between Caucasian and East Asian patients

S-1 is an oral fluoropyrimidine anti-neoplastic agent that is converted by CYP2A6 to 5-fluorouracil (5FU). We prospectively studied the pharmacokinetics and pharmacodynamics of S-1 in two groups of East Asian and Caucasian patients with solid malignancy refractory to standard chemotherapy, or for which 5FU was indicated, to elucidate differences in relation to CYP2A6 genotype and phenotype. S-1 was given orally at 30 mg/m(2) b.i.d. for 14 days every 21 days. Dose normalized AUC(0-48 h) for tegafur (P = 0.05) and gimeracil (P = 0.036) were higher in East Asians; conversely, AUC(0-48 h) of fluoro-β-alanine was higher in Caucasians (P = 0.044). Exposure to 5FU was similar in both groups (P = 0.967). Mean cotinine:nicotine ratio was 54% higher in the Caucasian group (P = 0.03), and correlated with oral clearance of tegafur (r = 0.59; P = 0.002). Grade 3/4 gastrointestinal toxicities were more common in Caucasians than Asians (21%vs 0%). Treatment with S-1 yields no significant difference in 5FU exposure between Caucasians and East Asians.

Phase II study of S-1 in patients with advanced biliary tract cancer

The aim of this study was to investigate the efficacy and safety of an oral fluoropyrimidine derivative, S-1, in patients with advanced biliary tract cancer. Patients with pathologically confirmed advanced biliary tract cancer, a measurable lesion, and no history of radiotherapy or chemotherapy were enrolled. S-1 was administered orally (40 mg m(-2) b.i.d.) for 28 days, followed by a 14-day rest period. A pharmacokinetic study was performed on day 1 in the initial eight patients. In all, 19 consecutive eligible patients were enrolled in the study between July 2000 and January 2002. The site of the primary tumour was the gallbladder (n=16), the extrahepatic bile ducts (n=2), and the ampulla of Vater (n=1). A median of two courses of treatment (range, 1-12) was administered. Four patients achieved a partial response, giving an overall response rate of 21.1%. The median time-to-progression and median overall survival period were 3.7 and 8.3 months, respectively. Although grade 3 anorexia and fatigue occurred in two patients each (10.5%), no grade 4 toxicities were observed. The pharmacokinetic parameters after a single oral administration of S-1 were similar to those of patients with other cancers. S-1 exhibits definite antitumour activity and is well tolerated in patients with advanced biliary tract cancer.

Randomized phase III study comparing the efficacy and safety of irinotecan plus S-1 with S-1 alone as first-line treatment for advanced gastric cancer (study GC0301/TOP-002)

BACKGROUND

Irinotecan hydrochloride and S-1, an oral fluoropyrimidine, have shown antitumor activity against advanced gastric cancer as single agents in phase I/II studies. The combination of irinotecan and S-1 (IRI-S) is also active against advanced gastric cancer. This study was conducted to compare the efficacy and safety of IRI-S versus S-1 monotherapy in patients with advanced or recurrent gastric cancer.

METHODS

Patients were randomly assigned to oral S-1 (80 mg/m² daily for 28 days every 6 weeks) or oral S-1 (80 mg/m² daily for 21 days every 5 weeks) plus irinotecan (80 mg/m² by intravenous infusion on days 1 and 15 every 5 weeks) (IRI-S). The primary endpoint was overall survival. Secondary endpoints included the time to treatment failure, 1- and 2-year survival rates, response rate, and safety.

RESULTS

The median survival time with IRI-S versus S-1 monotherapy was 12.8 versus 10.5 months (P = 0.233), time to treatment failure was 4.5 versus 3.6 months (P = 0.157), and the 1-year survival rate was 52.0 versus 44.9%, respectively. The response rate was significantly higher for IRI-S than for S-1 monotherapy (41.5 vs. 26.9%, P = 0.035). Neutropenia and diarrhea occurred more frequently with IRI-S, but were manageable. Patients treated with IRI-S received more courses of therapy at a relative dose intensity similar to that of S-1 monotherapy.

CONCLUSIONS

Although IRI-S achieved longer median survival than S-1 monotherapy and was well tolerated, it did not show significant superiority in this study.

S-1 as adjuvant chemotherapy for stage III colon cancer: a randomized phase III study (ACTS-CC trial)

BACKGROUND

S-1 is an oral fluoropyrimidine whose antitumor effects have been demonstrated in treating various gastrointestinal cancers, including metastatic colon cancer, when administered as monotherapy or in combination chemotherapy. We conducted a randomized phase III study investigating the efficacy of S-1 as adjuvant chemotherapy for colon cancer by evaluating its noninferiority to tegafur-uracil plus leucovorin (UFT/LV).

PATIENTS AND METHODS

Patients aged 20-80 years with curatively resected stage III colon cancer were randomly assigned to receive S-1 (80-120 mg/day on days 1-28 every 42 days; four courses) or UFT/LV (UFT: 300-600 mg/day and LV: 75 mg/day on days 1-28 every 35 days; five courses). The primary end point was disease-free survival (DFS) at 3 years.

RESULTS

A total of 1518 patients (758 and 760 in the S-1 and UFT/LV group, respectively) were included in the full analysis set. The 3-year DFS rate was 75.5% and 72.5% in the S-1 and UFT/LV group, respectively. The stratified hazard ratio for DFS in the S-1 group compared with the UFT/LV group was 0.85 (95% confidence interval: 0.70-1.03), demonstrating the noninferiority of S-1 (noninferiority stratified log-rank test, P < 0.001). In the subgroup analysis, no significant interactions were identified between the major baseline characteristics and the treatment groups.

CONCLUSION

Adjuvant chemotherapy using S-1 for stage III colon cancer was confirmed to be noninferior in DFS compared with UFT/LV. S-1 could be a new treatment option as adjuvant chemotherapy for colon cancer.

CLINICALTRIALSGOV

NCT00660894.

An early phase II study of S-1 in patients with metastatic pancreatic cancer

OBJECTIVE

The aim of this study was to evaluate the efficacy and toxicity of S-1 in patients with metastatic pancreatic cancer.

METHODS

Patients were required to have a histological diagnosis of pancreatic adenocarcinoma with measurable metastatic lesions, and no prior chemotherapy. S-1 was administered orally at 40 mg/m2 twice daily for 28 days with a rest period of 14 days as one course. Administration was repeated until the appearance of disease progression or unacceptable toxicity. A pharmacokinetic study was done on day 1 in the initial 8 patients.

RESULTS

Nineteen patients were entered into this study. Four patients (21.1%) achieved a partial response with a 95% confidence interval of 6.1-45.6%. No change was noted in 10 patients (52.6%), and progressive disease in 5 patients (26.3%). The median survival time was 5.6 months with a one-year survival rate of 15.8%. The major adverse events were gastrointestinal toxicities such as nausea and anorexia, though most of them were tolerable and reversible. There were no large differences in the pharmacokinetic parameters of S-1 in patients with pancreatic cancer and those in patients with other cancers.

CONCLUSION

S-1 is active and tolerated in patients with metastatic pancreatic cancer, which will be confirmed in the following large-scale phase II study.

A phase II study of S-1 in gemcitabine-refractory metastatic pancreatic cancer

PURPOSE

Gemcitabine monotherapy or gemcitabine-containing combination chemotherapy is the standard first-line therapy for advanced pancreatic cancer. After disease progression, there is no standard regimen available. In a previous phase II trial, S-1 has been reported to show considerable efficacy, achieving a response rate of 37.5% in chemo-naïve patients with pancreatic cancer. This study evaluated the efficacy and toxicity of S-1 in patients with gemcitabine-refractory metastatic pancreatic cancer.

METHODS

Eligibility criteria were histologically proven pancreatic adenocarcinoma with confirmation of progressive disease while receiving gemcitabine-based first-line chemotherapy, 20-74 years of age, Karnofsky performance status of 80-100 points, with measurable metastatic lesions, adequate hematological, renal and liver functions, and written informed consent. S-1 was administered orally at 40 mg/m(2) twice daily for 28 days with a rest period of 14 days as one course. Administration was repeated until the appearance of disease progression or unacceptable toxicity. The primary endpoint of this study was an objective response, and secondary endpoints included toxicity, progression-free survival (PFS) and overall survival, as well as clinical benefit response in symptomatic patients.

RESULTS

Forty patients from two institutions were enrolled between September 2004 and November 2005. The most common adverse reactions were fatigue and anorexia, although most of those adverse reactions were tolerable and reversible. One patient developed grade 3 pneumonitis without neutropenia and recovered with appropriate antibiotic treatment. Although no complete response was seen, partial response was obtained in six patients (15, 95% confidence interval, 3.9-26%). Stable disease was noted in 17 patients (43%), and progressive disease in 15 patients (38%). Out of 19 evaluable patients, a clinical benefit response was observed in four patients (21%). The median PFS was 2.0 months, and the median survival time was 4.5 months with a 1-year survival rate of 14.1%.

CONCLUSION

S-1 as monotherapy had marginal anti-tumor activity with tolerable toxicity in patients with gemcitabine refractory metastatic pancreatic cancer.

Phase II trial with S-1 in chemotherapy-naïve patients with gastric cancer. A trial performed by the EORTC Early Clinical Studies Group (ECSG)

S-1 is a new oral fluorinated pyrimidine derivate, in which the oral 5-fluorouracil (5-FU) prodrug, tegafur, was combined with two 5-FU-modulating substances, 5-chloro-2,4-dihydroxypyridine (gimeracil), and potassium oxonate (oteracil), at a molar ratio of 1:0.4:1. The final mechanism of action is exerted by 5-FU. The present study is the first European phase II trial of S-1 in gastric cancer. The primary study objectives were the safety, toxicity and activity of S-1 in non-pretreated patients with gastric cancer. The secondary objective was the duration of response. Patients had to have histologically- or cytologically-verified metastatic or locally advanced, unresectable gastric cancer; S-1 was administered orally twice daily at 40, then 35 mg/m(2) for 28 days every 5 weeks. The starting dose of 40 mg/m(2) was found to be intolerable due to significant non-haematological toxicity, and this dose was rapidly reduced to 35 mg/m(2) twice daily. Of the 7 patients enrolled at the 40 mg/m(2) level, only 3 were evaluable. At 35 mg/m(2), a response rate of 26.1% (95% Confidence Interval (CI) 12.0-45.1%) in 23 enrolled patients, and 31.6% (C.I. 14.7-53.0%) in 19 evaluable patients according to an independent radiology review, was found. The median duration of response at 35 mg/m(2) (6 patients) was 223 days (range, 108-828 days), and of stable disease was 111 days (range 68-411 days). S-1 can be administered with an acceptable safety and toxicity in European patients at a dose of 35 mg/m(2) days 1 - 28 every 5 weeks and is associated with a moderate response rate similar to the results achieved with other fluoropyrimidines.

Randomized scheduling feasibility study of S-1 for adjuvant chemotherapy in advanced head and neck cancer

The purpose of this study was to determine the feasible adjuvant therapy administration schedule of S-1 for locoregionally advanced squamous cell carcinoma of the head and neck (SCCHN). Patients receiving definitive treatments were randomly assigned to either arm A (51 cases) receiving oral S-1 of 2-week administration followed by 1-week rest for 6 months, or arm B receiving S-1 of 4-week administration followed by 2-week rest for 6 months. Planned treatment was given in 40% of patients in arm A and 29% in arm B. The cumulative rates of the relative total administration dose of S-1 at 100% were 54.9% (95% CI: 40.1–69.7%) in arm A and 34.3% (95% CI: 21.1–47.4%) in arm B, respectively (P=0.054). Adverse events were recorded in 41 patients (82.0%) in arm A and 48 patients (94.1%) in arm B (P=0.060). The incidences of diarrhoea (10 vs 28%; P<0.05) and skin toxicities (18 vs 37%; P<0.05) were significantly higher in arm B. One-year disease-free survival was similar in both arms: arm A 81.2% (95% CI: 70.0–92.4%); arm B 77.0% (95% CI: 65.0–89.0%). The schedule of 2-week administration followed by 1-week rest seems to be more feasible for oral 6-month administration of S-1 in adjuvant chemotherapy of locoregionally advanced SCCHN.

Predictive value of chemotherapy-induced neutropenia for the efficacy of oral fluoropyrimidine S-1 in advanced gastric carcinoma

Myelosuppression that occurs during chemotherapy has been reported to be a predictor of better survival in patients with breast or lung carcinomas. We evaluated the prognostic implications of chemotherapy-induced neutropenia in advanced gastric carcinoma. Data from a prospective survey of oral fluoropyrimidine S-1 for advanced gastric cancer patients in Japan were reviewed. We identified 1055 untreated patients with adequate baseline bone marrow function. During treatment with S-1, a total of 293 (28%) patients experienced grade 1 or higher neutropenia. The adjusted hazard ratio of death for the presence of neutropenia, as compared with the absence of such toxicity, from a multivariate Cox model was 0.72 (95% confidence interval, 0.54–0.95; P=0.0189) for grade 1 neutropenia, 0.63 (0.50–0.78; P<0.0001) for grade 2 neutropenia and 0.71 (0.51–0.98; P=0.0388) for grade 3–4 neutropenia. These findings suggest that the occurrence of neutropenia during chemotherapy is an independent predictor of increased survival in patients with advanced gastric cancer, whereas the absence of such toxicity indicates that the dosages of drugs are not pharmacologically adequate. Monitoring of neutropenia in patients who receive chemotherapy may contribute to improved drug efficacy and favourable survival.

Multicenter phase II study of S-1 monotherapy as second-line chemotherapy for advanced biliary tract cancer refractory to gemcitabine

Gemcitabine is widely used for the treatment of advanced biliary tract cancer (BTC) as first-line chemotherapy. However, there is no standard chemotherapy for patient with advanced BTC refractory to gemcitabine. We conducted a multicenter phase II study of S-1 monotherapy as second-line chemotherapy for patients with advanced BTC that were refractory to gemcitabine. S-1 was administered orally at a dose of 80 mg/m(2) for 28 days, followed by 14 days of rest. This regimen was repeated every 6 weeks. Tumor response was assessed every two cycles using the Response Evaluation Criteria in Solid Tumors version 1.0. Twenty-two patients were enrolled between March 2007 and January 2010, with 14 patients (64%) representing cases of recurrence after surgery. The overall response rate was 22.7%, and the overall disease control rate was 50.0%. The median overall survival time was 13.5 months (95% CI, 7.1-23.1 months) and the median time-to-progression was 5.4 months (95% CI, 2.6-17.2 months). Grade 3/4 toxicities included neutropenia (5%) and anemia (5%). The most common non-hematological toxicities were nausea (27%), anorexia (55%), and pigmentation (32%). In conclusion, S-1 monotherapy is feasible and moderately efficacious second-line chemotherapy for advanced BTC.

Protective effects of Rhizoma smilacis glabrae extracts on potassium oxonate- and monosodium urate-induced hyperuricemia and gout in mice

BACKGROUND

Rhizoma smilacis glabrae (RSG, tufuling) has been widely used in traditional Chinese medicine for deoxidation, dampness relief, and easing joint movement. The chemical composition of RSG has been systematically confirmed, and some of its compounds have been revealed to possess antioxidant, anti-inflammatory, immunomodulatory, hypouricemic, and hepatoprotective effects.

PURPOSE

We aimed to clarify whether a RSG extract attenuates hyperuricemia, paw edema, and renal injury in mice with potassium oxonate (PO)- and monosodium urate (MSU)-induced chronic hyperuricemia and gout.

METHODS

RSG water extract was obtained and analyzed by HPLC-DAD-MS/MS. To establish a murine model with chronic hyperuricemia and gout, PO was orally administered daily from day 0 to day 24, whereas MSU was injected into the tibiotarsal joint on day 21. The mice in the drug intervention groups were treated once daily with doses of allopurinol or RSG extract from day 21 to day 24. The diameter of the ankle joints was measured with calipers. Serum TNF-α and IL-1β concentrations, hepatic XOD activity, and uric acid, creatinine, and blood urea nitrogen (BUN) levels were also determined. The right kidney and articular cavities were fixed, cut into sections, and stained with hematoxylin and eosin.

RESULTS

Nine compounds in the RSG water extract were unambiguously identified as 5-O-caffeoylshikimic acid, neoastilbin, astilbin, taxifolin, neoisoastilbin, isoastilbin, engeletin, isoengeletin, and trans-resveratrol. The RSGE treatment dose-dependently reduced PO- and MSU-induced paw edema, serum TNF-α, IL-1β, IL-6, IL-12, uric acid, and BUN, while significantly elevated serum IL-10, urinary uric acid and creatinine levels as compared with the respective values in the hyperuricemic and gouty mice group (vehicle group). Moreover, the hepatic XOD activity was dose-dependently reduced by the RSGE treatment. In addition, RSGE treatment not only ameliorated the infiltration of inflammatory cells, tubular dilation and vacuole formation in renal tubular, but also improved the synovial hyperplasia, reduced inflammatory cells infiltration into the synovium, and diminished the erosive damage in the cartilage.

CONCLUSION

The murine model with chronic hyperuricemia and gout be built in present study is consistent with the clinical symptoms of patients with long-standing hyperuricemia and acute gouty arthritis. RSG water extract has potent efficacy in ameliorating murine hyperuricemia and gout induced by PO and MSU.

A multicenter phase II study of combined chemotherapy with docetaxel, cisplatin, and S-1 in patients with unresectable or recurrent gastric cancer (KDOG 0601)

PURPOSE

We conducted a phase II study to evaluate the efficacy and safety of a triplet regimen of docetaxel, cisplatin, and S-1 in patients with unresectable or recurrent gastric cancer.

METHODS

Docetaxel (40 mg/m(2)) and cisplatin (70 or 60 mg/m(2)) were given on day 1 of a 28-day cycle. S-1 (40 mg/m(2)) was given twice daily on days 1-14. Treatment with this regimen was continued for a maximum of 6 cycles. Subsequently, patients with no disease progression received a combination of docetaxel and S-1.

RESULTS

Fifty-nine patients were enrolled. The median number of administered cycles was 8 (range, 1-25). Because some patients had serious myelosuppression and renal dysfunction with 70 mg/m(2) of cisplatin, dose of cisplatin was reduced to 60 mg/m(2) after 19 patients had been treated. Common severe toxic effects of grade 3 or 4 were leukocytopenia (44%), neutropenia (72%), anemia (15%), and febrile neutropenia (14%). The overall response rate of this group was 81% (95% confidence interval (CI), 71-91%). The median overall survival and progression-free survival were 18.5 (95% CI, 15.6-21.5) and 8.7 (95% CI, 6.7-10.7) months, respectively.

CONCLUSIONS

Triplet of docetaxel, cisplatin, and S-1 is a well-tolerated and highly active regimen for advanced or recurrent gastric cancer. A 60 mg/m(2) of cisplatin is as effective as 70 mg/m(2) of cisplatin.

A phase II study of S-1 in patients with metastatic breast cancer — A Japanese trial by the S-1 cooperative study group, breast cancer working group

BACKGROUND

S-1 is a newly developed novel oral dihydrouracil dehydrogenase inhibiting fluoropyrimidine drug consisting of 1 M tegafur (FT), 0.4 M 5-chloro-2, 4-dihydroxypyrimidine (gimeracil), and 1 M potassium oxonate (oteracil), with efficient antitumor activity and low gastrointestinal toxicity which is widely used in Japan against advanced gastric, head and neck cancers. We investigated its clinical efficacy against metastatic breast cancer.

METHODS

A non-blind phase II study was carried out to evaluate the efficacy and toxicity in metastatic breast cancer patients. Patients with measurable metastasis foci (n=111) were enrolled, and 108 patients were regarded as eligible. S-1 was administered orally at a standard dose of 80 mg/m2/day b.i.d. One course consisted of 28 consecutive days of administration followed by a 14-day rest, and courses were repeated up to six times.

RESULTS

Among the eligible patients, 10 had a complete response and 35 had a partial response, with an overall response rate (CR+PR) of 41.7% (95% confidence interval: CI, 32.3-51.5%). The incidences of toxicity (> or =grade 3) were neutropenia 9.1%, anemia 0.9%, anorexia 3.6%, stomatitis 1.8%, nausea/vomiting 1.8%, diarrhea 0.9%, and fatigue 2.7%, however no treatment-related deaths were observed. The median survival time was 872 days (95% CI, 572-1,110 days). There was no difference in response rate or toxicity between the under 65-year-old group and the older group.

CONCLUSION

S-1 was demonstrated to have high efficacy with low gastrointestinal toxicity even in older patients and will be a promising new chemotherapy drug for metastatic breast cancer.

Phase I/II study of docetaxel and S-1 in patients with advanced gastric cancer

The aims of this phase I/II study of docetaxel and S-1 were to determine the dose-limiting toxicity (DLT), maximum-tolerated dose (MTD), and recommended dose (RD) in the phase I part and to explore the tumour response, survival and safety in the phase II part. Patients with histologically- or cytologically confirmed unresectable or recurrent gastric cancer were eligible. Treatment consisted of intravenous docetaxel on day 1 (starting dose 50 mg m⁻²) and oral S-1 at a fixed dose of 40 mg m⁻² twice daily on days 1–14, every 4 weeks up to six cycles. Nine patients took part in the phase I portion of the study. The MTD of docetaxel was determined to be 50 mg m⁻², with the DLTs of grade 3 infection associated with grade 3 neutropenia and grade 4 neutropenia during S-1 administration. The RD of docetaxel was 40 mg m⁻² in combination with S-1 40 mg m⁻² b.i.d. The efficacy and safety of this regimen was therefore assessed in 46 patients with at least one measurable lesion. The overall response rate and estimated median overall survival were 46% (95% CI, 31–61%) and 14.0 months (8.3–17.3 months), respectively. The most common grade 3/4 toxicity was neutropenia (67% of patients), which was predictable and manageable. This regimen showed promising activity with moderate toxicities in advanced gastric cancer.

EORTC Early Clinical Studies Group early phase II trial of S-1 in patients with advanced or metastatic colorectal cancer

Cancer of the colon and rectum is one of the most frequent malignancies both in the US and Europe. Standard palliative therapy is based on 5-fluorouracil/folinic acid combinations, with or without oxaliplatin or irinotecan, given intravenously. Oral medication has the advantage of greater patient convenience and acceptance and potential cost savings. S-1 is a new oral fluorinated pyrimidine derivative. In a nonrandomized phase II study, patients with advanced/metastatic colorectal cancer were treated with S-1 at 40 mg m-2 b.i.d. for 28 consecutive days, repeated every 5 weeks, but by amendment the dose was reduced to 35 mg m-2 during the study because of a higher than expected number of severe adverse drug reactions. In total 47 patients with colorectal cancer were included. In the 37 evaluable patients there were nine partial responses (24%), 17 stable diseases (46%) and 11 patients had progressive disease (30%). Diarrhoea occurred frequently and was often severe: in the 40 and 35 mg m-2 group, respectively, 38 and 35% of the patients experienced grade 3-4 diarrhoea. The other toxicities were limited and manageable. S-1 is active in advanced colorectal cancer, but in order to establish a safer dose the drug should be subject to further investigations.