Phase I/II study of oxaliplatin with oral S-1 as first-line therapy for patients with metastatic colorectal cancer

Nanoparticle-mediated metronomic chemotherapy in cancer: A paradigm of precision and persistence

Current methods of cancer therapy have demonstrated enormous potential in tumor inhibition. However, a high dosage regimen of chemotherapy results in various complications which affect the normal body cells. Tumor cells also develop resistance against the prescribed drugs in the whole treatment regimen increasing the risk of cancer relapse. Metronomic chemotherapy is a modern treatment method that involves administering drugs at low doses continuously, allowing the drug sufficient time to take its effect. This method ensures that the toxicity of the drugs is to a minimum in comparison to conventional chemotherapy. Nanoparticles have shown efficacy in delivering drugs to the tumor cells in various cancer therapies. Combining nanoparticles with metronomic chemotherapy can yield better treatment results. This combination stimulates the immune system, improving cancer cells recognition by immune cells. Evidence from clinical and pre-clinical trials supports the use of metronomic delivery for drug-loaded nanoparticles. This review focuses on the functionalization of nanoparticles for improved drug delivery and inhibition of tumor growth. It emphasizes the mechanisms of metronomic chemotherapy and its conjunction with nanotechnology. Additionally, it explores tumor progression and the current methods of chemotherapy. The challenges associated with nano-based metronomic chemotherapy are outlined, paving the way for prospects in this dynamic field.

Multicenter randomized phase II study on S-1 and oxaliplatin therapy as an adjuvant after hepatectomy for colorectal liver metastases (YCOG1001)

PURPOSE

The high recurrence rate of colorectal cancer liver metastasis (CRCLM) after surgery remains a crucial problem. However, adjuvant chemotherapy after hepatectomy for CRCLM has not yet been established. This study evaluated the efficacy of adjuvant therapy with S-1 and oxaliplatin (SOX).

METHODS

In a multicenter, randomized, phase II study, patients undergoing curative resection of CRCLM were randomly enrolled in a 1:1 ratio to either the low- or high-dose group. S-1 and oxaliplatin were administered from days 1 to 14 of a 3-week cycle as a 2-h infusion every 3 weeks. The dose of S-1 was fixed at 80 mg/m2. The doses in the low- and high-dose oxaliplatin groups were 100 mg/m2 (low-dose group) and 130 mg/m2 (high-dose group), respectively. This treatment was repeated eight times. The primary endpoint was the rate of discontinuation owing to toxicity. The secondary endpoints were the relapse-free survival (RFS) and frequency of adverse events (AEs).

RESULTS

Between August 2010 and March 2015, 44 patients (low-dose group: 31 patients and high-dose group: 13 patients) were enrolled in the study. Of these, one patient was excluded from the efficacy analysis. In the high-dose group, five of nine patients were unable to continue the study due to toxicity in February 2013. At that time, recruitment to the high-dose group was stopped from the protocol. The relative dose intensity (RDI) for S-1 in the low- and high-dose groups were 49.8 and 48.7% (p = 0.712), and that for oxaliplatin was 75.9 and 73.0% (p = 0.528), respectively. The rates of discontinuation due to toxicity were 60 and 53.8% in the low- and high-dose groups, respectively, with no marked difference noted between the groups (p = 0.747). The frequency of grade ≥ 3 common adverse events was neutropenia (23.3%/23.1%), diarrhea (13.3%/15.4%), and peripheral sensory neuropathy (6.7%/7.7%). The disease-free survival (DFS) at 3 years was 52.9% in the low-dose group, which was not significantly different from that in the high-dose group (46.2%; p = 0.705).

CONCLUSIONS

SOX regimens as adjuvant therapy after hepatectomy for CRCLM had high rates of discontinuation due to toxicity in both groups. In particular, the RDI of S-1 was < 50%. Therefore, the SOX regimen is not recommended as adjuvant chemotherapy after hepatectomy for CRCLM.

A Prospective Multicenter Phase II Study on the Feasibility and Efficacy of S-1 and Oxaliplatin Neoadjuvant Chemotherapy for Locally Advanced Rectal Cancer

BACKGROUND

Neoadjuvant chemoradiotherapy and total mesorectal excision compose the standard of care for rectal cancer in multiple guidelines. However, neoadjuvant chemoradiotherapy has not exhibited clear survival benefits but rather has led to an increase in adverse events. Conversely, neoadjuvant chemotherapy is expected to prevent adverse events caused by radiation, yet this treatment is still controversial.

OBJECTIVE

The purpose of this study was to evaluate the feasibility and efficacy of S-1 and oxaliplatin neoadjuvant chemotherapy together with total mesorectal excision for resectable locally advanced rectal cancer.

DESIGN

The study was a prospective, single-arm phase II trial.

SETTINGS

The study was conducted at multiple institutions.

PATIENTS

Fifty-eight patients with resectable locally advanced rectal cancer were enrolled.

INTERVENTION

Three cycles of S-1 and oxaliplatin were administered before surgery. S-1 was administered orally at 80 mg/m2 per day for 14 consecutive days, followed by a 7-day resting period. Oxaliplatin was given intravenously on the first day at a dose of 130 mg/m2 per day. The duration of 1 cycle was considered to be 21 days. Total mesorectal excision with bilateral lymph node dissection was carried out after neoadjuvant chemotherapy.

MAIN OUTCOME MEASURES

The study was designed to detect the feasibility and efficacy of S-1 and oxaliplatin as neoadjuvant chemotherapy.

RESULTS

The completion rate of 3 courses of S-1 and oxaliplatin as neoadjuvant chemotherapy was 94.8% (55/58). The reasons for discontinuation were thrombocytopenia (3.4%) and liver injury (1.7%). The most common severe (grade ≥3) adverse effect of neoadjuvant chemotherapy was thrombocytopenia (3.4%). There were no severe adverse clinical symptoms. Consequently, R0 resection was achieved in 51 (98.1%) of 52 patients. Pathologic complete response occurred in 10 patients (19.2%).

LIMITATIONS

This was a single-arm, nonrandomized phase II study.

CONCLUSIONS

The combination of S-1 and oxaliplatin neoadjuvant chemotherapy and total mesorectal excision is a feasible and promising treatment option for resectable locally advanced rectal cancer. See Video Abstract at http://links.lww.com/DCR/B555.

UN ESTUDIO PROSPECTIVO MULTICNTRICO FASE II SOBRE LA FACTIBILIDAD Y EFICACIA DE LA QUIMIOTERAPIA NEOADYUVANTE SCON OXALIPLATINO PARA EL CNCER DE RECTO LOCALMENTE AVANZADO

ANTECEDENTES:La quimiorradioterapia neoadyuvante y la escisión mesorrectal total constituyen el estándar de atención para el cáncer de recto en varias guías. Sin embargo, la quimiorradioterapia neoadyuvante no ha mostrado beneficios claros en la sobrevida, pero si ha creado un aumento de eventos adversos. Por otro lado, se espera que la quimioterapia neoadyuvante prevenga los eventos adversos asociados a la radiación, aunque este tratamiento sigue siendo controvertido.OBJETIVO:Evaluar la factibilidad y eficacia de la quimioterapia neoadyuvante S-1 con oxaliplatino en conjunto con la escisión mesorrectal total para el cáncer de recto localmente avanzado resecable.DISEÑO:El estudio fue un ensayo prospectivo fase II de brazo único.AMBITO:Estudio realizado en múltiples instituciones.PACIENTES:Se incluyeron 58 pacientes con cáncer de recto localmente avanzado resecable.INTERVENCIÓN:Se administraron tres ciclos de S-1 con oxaliplatino antes de la cirugía. Se administró S-1 por vía oral a 80 mg / m2 / día durante 14 días consecutivos, seguido de un período de descanso de 7 días. El oxaliplatino se administró por vía intravenosa el primer día a una dosis de 130 mg / m2 / día. Se consideró la duración de un ciclo de 21 días. Posterior a la quimioterapia neoadyuvante se realizó la excisión total mesorrectal con disección ganglionar bilateral.PRINCIPALES VARIABLES EVALUDADAS:El estudio fue diseñado para conocer la factibilidad y eficacia de S-1 con oxaliplatino como quimioterapia neoadyuvante.RESULTADOS:La tasa de conclusión con tres ciclos de S-1 con oxaliplatino como quimioterapia neoadyuvante fue del 94,8% (55/58). Los motivos de interrupción fueron trombocitopenia (3,4%) y daño hepático (1,7%). El efecto adverso grave más común (grado ≥ 3) de la quimioterapia neoadyuvante fue la trombocitopenia (3,4%). No hubo síntomas clínicos adversos graves. Como resultado, la resección R0 se logró en 51 de 52 pacientes (98,1%). Una respuesta patológica completa se obtuvo en 10 pacientes (19,2%).LIMITACIONES:Fue un estudio de fase II no aleatorizado de un solo brazo.CONCLUSIONES:La combinación de S-1 con oxaliplatino como quimioterapia neoadyuvante y escisión mesorrectal total es factible y es una opción de tratamiento prometedora para el cáncer de recto localmente avanzado resecable. Consulte Video Resumen en http://links.lww.com/DCR/B555. (Traducción-Dr Juan Antonio Villanueva-Herrero).

Impact of sex and histology on the therapeutic effects of fluoropyrimidines and oxaliplatin plus bevacizumab for patients with metastatic colorectal cancer in the SOFT trial

Mechanisms accounting for sex differences in the incidence of adverse events caused by fluoropyrimidine treatments, and histologic differences in efficacy are insufficiently understood. We determined differences between the sexes in terms of the safety of S-1 plus oxaliplatin (SOX)/bevacizumab-versus-l-leucovorin, 5-fluorouracil (5-FU) and oxaliplatin (FOLFOX)/bevacizumab, and the impact of histology on their therapeutic effects, in 512 unresectable metastatic colorectal cancer patients from the SOFT phase III study. Nausea (OR: 2.88, P < 0.001) and vomiting (OR: 3.04, P = 0.005) occurred more frequently in females than males treated with SOX/bevacizumab, while nausea (OR: 2.12, P = 0.006), vomiting (OR: 3.26, P = 0.004), leukopenia (OR: 2.61, P < 0.001), neutropenia (OR: 2.92, P < 0.001), and alopecia (OR: 4.13, P < 0.001) were higher in females on FOLFOX/bevacizumab. Mean relative dose intensities (RDIs) of S-1 during all cycles of SOX/bevacizumab were significantly lower in females (73.9%) than males (81.5%) (P < 0.001), while RDIs of continuous infusion of 5-FU in the FOLFOX/bevacizumab regimen were 75.0% in females and 80.5% in males (P = 0.005). No significant differences in efficacy with regard to overall survival (OS) and progression-free survival (PFS) were identified between the sexes for either SOX/bevacizumab or FOLFOX/bevacizumab treatment. Patients with poorly-differentiated adenocarcinoma had significantly worse OS (HR: 2.72, 95% CI: 1.67-4.44, P < 0.0001) and PFS (HR: 1.89, 95% CI: 1.18-3.02, P = 0.0079) than patients with well- or moderately-differentiated adenocarcinoma. Female patients experienced more frequent and severe adverse reactions to SOX/bevacizumab and FOLFOX/bevacizumab and a worse prognosis for poorly-differentiated adenocarcinoma were confirmed in this phase III study. This warrants further translational research to identify the responsible mechanisms.

A phase I study of docetaxel/oxaliplatin/S-1 (DOS) combination neoadjuvant chemotherapy for patients with locally advanced adenocarcinoma of the esophagogastric junction

BACKGROUND

The optimal dose of each drug used in the docetaxel, oxaliplatin, and S-1 (DOS) chemotherapy remains to be clarified for the Japanese population. The purpose of this study was to determine a recommended dose for a combination neoadjuvant DOS chemotherapy for Japanese patients with locally advanced adenocarcinoma of the esophagogastric junction (AEG).

METHODS

Patients with cT3 or more advanced AEG without distant metastasis were eligible for this study. The planned dosages of docetaxel (mg/m², day 1), oxaliplatin (mg/m², day 1), and S-1 (mg/day, days 1-14) were: 50/100/80-120 at level 1, and 60/100/80-120 at level 2, respectively. The treatment cycle was repeated every 3 weeks, and patients were assessed for response to the treatment after 2 and 3 cycles. This study was registered in the UMIN Clinical Trial Registry (UMIN 000022210).

RESULTS

We enrolled 12 patients with locally advanced AEG in this study. At dose level 1, one of the six patients experienced dose-limiting toxicity (DLT) of grade 3 diarrhea and grade 3 febrile neutropenia. Two of the next six patients also experienced DLT of need for more than 2-week delay of the start of the second cycle due to adverse events at dose level 2. Based on these results, level 2 was considered the recommended dose for this regimen.

CONCLUSION

Recommended doses of docetaxel (mg/m²), oxaliplatin (mg/m²), and S-1 (mg/day) were 60/100/80-120. This chemotherapy scheme showed good preliminary efficacy with acceptable toxicity warranting a further phase II trial to investigate the efficacy of this regimen.

A Study of the S-1 or Capecitabine as First-line Regimen in Patients with Metastatic Colorectal Cancer: A Real World Study

Objectives: To compare the 2-year overall survival (OS) rate and safety between patients using S-1 and capecitabine in the first-treatment of metastatic colorectal cancer in the real clinical setting. Methods: In this retrospective cohort study, patients satisfying the following criteria were identified from 10 centers in China. The 2-year OS rate and safety were assessed. The propensity score matching (PSM) was used to control basic characteristics of the two groups to balance the processing bias and confoundings. Results: A total of 1367 patients were identified, 824 patients accepted capecitabine and 546 patients accepted S-1. After PSM, 533 eligible patients were included in each group without statistical significance in age, sex, BMI, KPS score and comorbidities. The 2-year OS rate between two groups was without significant statistical difference (61.9% vs. 62.9%, p=0.4295). The subgroup analysis showed that the 2-year OS rate had no significant difference between men and women, younger and older than 60 years old, different metastatic sites, different chemotherapy courses between S-1 and capecitabine groups. The hematological adverse events were all without statistical difference between two groups, but the incidence of diarrhea (16.4% vs. 23.6%, p=0.0018) and hand-foot syndrome (28.7% vs. 46.7%, p<0.001) in S-1 group were lower than those in the capecitabine group. Conclusions: Compared to capecitabine, S-1 had a similar 2-year OS rate but had a lower incidence of adverse events in the real clinical setting. So, S-1 could be a good choice in the first-treatment of patients with metastatic colorectal cancer in China.

Phase 2 study of perioperative chemotherapy with SOX and surgery for stage III colorectal cancer (SOS3 study)

This phase 2 study evaluated the safety and efficacy of perioperative chemotherapy with S-1 plus oxaliplatin (SOX) for stage III colorectal cancer (CRC). Patients with stage III CRC received surgery after neoadjuvant chemotherapy (NAC; SOX 4 cycles) and adjuvant chemotherapy (AC; SOX 4 cycles). The primary endpoints were response rate and safety. We enrolled 30 patients. Their median age was 62 years (range: 43-87 years); 53% were women. They received a median of 4 cycles (range: 1-4) of NAC and a median 4 cycles (range: 0-4) of AC. Five patients interrupted NAC treatment because of toxicity (grade 3 diarrhoea [n = 1], grade 3 ileus [n = 1], and grade 3-4 thrombocytopenia [n = 3]). Patients' responses were complete responses: n = 2 (6.6%), partial responses: n = 21 (70%), stable disease: n = 6 (20.0%), and progressive disease: n = 1 (3.3%; response rate: 73.3%). Curative resection was performed in 29 patients. No patients showed anastomotic leakage. Five-year overall survival and disease-free survival were 83.3% and 76.7%, respectively (median follow-up time: 48 months). NAC using SOX regimen is safe and effective, and may lead to reduced local recurrence and distant metastasis. Long-term outcomes are awaited to evaluate further the efficacy of this strategy (UMIN000006790).

S-1 and Oxaliplatin Versus Tegafur-uracil and Leucovorin as Postoperative Adjuvant Chemotherapy in Patients With High-risk Stage III Colon Cancer (ACTS-CC 02): A Randomized, Open-label, Multicenter, Phase III Superiority Trial

BACKGROUND

The efficacy of S-1 plus oxaliplatin (SOX) as postoperative adjuvant chemotherapy for colon cancer has not been established. This randomized phase III study was designed to verify the superiority of SOX over tegafur-uracil and leucovorin (UFT/LV) in patients with high-risk stage III colon cancer (any T, N2, or positive nodes around the origin of the feeding arteries).

PATIENTS AND METHODS

Patients who underwent curative resection for pathologically confirmed high-risk stage III colon cancer were randomly assigned to receive either UFT/LV (300 mg/m² of UFT and 75 mg/day of LV on days 1-28, every 35 days, 5 cycles) or SOX (100 mg/m² of oxaliplatin on day 1 and 80 mg/m² of S-1 on days 1-14, every 21 days, 8 cycles). The primary endpoint was disease-free survival (DFS).

RESULTS

A total of 478 patients in the UFT/LV group and 477 patients in the SOX group were included in the primary analysis. The 3-year DFS was 60.6% (95% confidence interval [CI], 56.0%-64.9%) in the UFT/LV group and 62.7% (95% CI, 58.1%-66.9%) in the SOX group. The stratified hazard ratio for DFS was 0.90 (95% CI, 0.74-1.09; stratified log-rank test, P = .2780). In the N2b subgroup, the 3-year DFS was 46.0% (95% CI, 37.5%-54.0%) in the UFT/LV group and 54.7% (95% CI, 45.7%-62.7%) in the SOX group (hazard ratio, 0.76; 95% CI, 0.55-1.05).

CONCLUSION

As postoperative adjuvant chemotherapy, SOX was not superior to UFT/LV in terms of DFS in patients with high-risk stage III colon cancer.

Sex differences in the safety of S-1 plus oxaliplatin and S-1 plus cisplatin for patients with metastatic gastric cancer

Previous studies have shown sex‐related differences in the incidence of adverse events following treatment with fluoropyrimidines, however the mechanism of this difference is unknown. We examined sex‐related differences in the safety of S‐1 plus oxaliplatin (SOX) and S‐1 plus cisplatin (CS) in 663 metastatic gastric cancer patients taking part in a phase III study. The incidences of leukopenia (odds ratio [OR] 1.9; P = .015), neutropenia (OR 2.2; P = .002), nausea (OR 2.0; P = .009), and vomiting (OR 2.8; P < .001) were increased in women versus men treated with SOX, while vomiting (OR 2.9; P < .001) and stomatitis (OR 1.8; P = .043) were increased in women versus men treated with CS. In contrast, male patients treated with CS experienced thrombocytopenia more often (OR 0.51; P = .009). The mean relative dose intensity of S‐1 in SOX was 75.4% in women and 81.4% in men (P = .032). No difference in efficacy was observed between women and men undergoing either regimen. Sex‐related differences in adverse reactions during SOX and CS treatment were confirmed in this phase III study. Further translational research studies are warranted to pursue the cause of this difference.

Phase II Study of the Triple Combination Chemotherapy of SOXIRI (S-1/Oxaliplatin/Irinotecan) in Patients with Unresectable Pancreatic Ductal Adenocarcinoma

LESSONS LEARNED

The triple combination chemotherapy of SOXIRI (S-1/oxaliplatin/irinotecan) in patients with unresectable pancreatic ductal adenocarcinoma was an effective treatment that appeared to be better tolerated than the widely used FOLFIRINOX regimen.SOXIRI regimen may provide an alternative approach for advanced pancreatic cancer.

BACKGROUND

In our previous phase I study, we determined the recommended dose of a biweekly S-1, oxaliplatin, and irinotecan (SOXIRI) regimen in patients with unresectable pancreatic ductal adenocarcinoma (PDAC). This phase II study was conducted to assess the safety and clinical efficacy in patients with unresectable PDAC.

METHODS

Patients with previously untreated metastatic and locally advanced PDAC were enrolled. The primary endpoint was response rate (RR). Secondary endpoints were adverse events (AEs), progression-free survival (PFS), and overall survival (OS). Patients received 80 mg/m² of S-1 twice a day for 2 weeks in alternate-day administration, 150 mg/m² of irinotecan on day 1, and 85 mg/m² of oxaliplatin on day 1 of a 2-week cycle.

RESULTS

Thirty-five enrolled patients received a median of six (range: 2-15) treatment cycles. The RR was 22.8% (95% confidence interval [CI]: 10.4-40.1); median OS, 17.7 months (95% CI: 9.8-22.0); and median PFS, 7.4 months (95% CI: 4.2-8.4). Furthermore, the median OS in patients with distant metastasis was 10.1 months, whereas that in patients with locally advanced PDAC was 22.6 months. Major grade 3 or 4 toxicity included neutropenia (54%), anemia (17%), febrile neutropenia (11%), anorexia (9%), diarrhea (9%), and nausea (9%). There were no treatment-related deaths.

CONCLUSION

SOXIRI is considered a promising and well-tolerated regimen in patients with unresectable PDAC.

Efficacy of the combination use of aprepitant and palonosetron for improving nausea in various moderately emetogenic chemotherapy regimens

BACKGROUND

Nausea is more difficult to control than vomiting in chemotherapy. We therefore analyzed the efficacy of a strong supportive treatment with aprepitant, palonosetron, and dexamethasone against nausea for various moderately emetogenic chemotherapy (MEC).

METHODS

A total of 312 cases treated by palonosetron with or without aprepitant receiving MEC regimens using oxaliplatin, carboplatin, and irinotecan from 2014 to 2016 in our outpatient center for digestive organ cancers, lung cancers, and gynecological cancers were analyzed. Through propensity score matching analysis, cases were divided into 97 cases receiving 2 drugs (palonosetron+dexamethasone) and 97 receiving 3 drugs (aprepitant+palonosetron+dexamethasone). We examined the control rates of nausea for the first two consecutive courses in the both groups. Additionally, risk factors for acute and delayed nausea were analyzed using a multivariate analysis among overall 312 cases.

RESULTS

The control rates of nausea in the two- and the three-drug groups were as follows: acute, 92.8 and 95.9% (p = 0.35); and delayed, 83.5 and 81.4% (p = 0.85), although the control rates of vomiting exceeded 95% in both groups. A multivariate analysis showed that significant risk factors for acute nausea (odds ratio, 95% confidence interval) were elevation of serum creatinine (12.601, 2.437-65.157), general fatigue (3.728, 1.098-12.661), and performance status (PS) 2 (19.829, 3.200-122.865). The significant risk factors for delayed nausea were elevation of alanine aminotransferase (2.397, 1.153-4.984), general fatigue (2.652, 1.380-5.097), and PS 2 (5.748, 1.392-23.740).

CONCLUSIONS

The control for nausea in MEC was insufficient even with palonosetron and aprepitant, and we should pay attention to risk factors for preventing nausea.

A phase II study of bevacizumab and irinotecan plus alternate-day S-1 as a second-line therapy in patients with metastatic colorectal cancer: the AIRS study

BACKGROUND

The aim of this single-arm phase II clinical trial was to evaluate whether the alternate-day administration of S-1 plus irinotecan would reduce the incidence of severe diarrhea in comparison to consecutive-day S-1 administration (standard IRIS regimen) in second-line treatment for patients with metastatic colorectal cancer.

METHODS

Patients with metastatic colorectal cancer after failure with first-line treatment of oxaliplatin and fluoropyrimidine were enrolled. Irinotecan (150 mg/m²) and bevacizumab (5 mg/kg) were given intravenously on day 1. Oral S-1 was administered on alternate days at a dose of 40-60 mg twice a day. Cycles were repeated every 2 weeks. The primary endpoint was the incidence of grade ≥ 3 diarrhea. Our hypothesis set 21% as a threshold incidence and 10% as an expected incidence from previous studies with one-sided alpha 0.05. The secondary endpoints included the relative dose intensity, progression-free survival, overall survival and other adverse events.

RESULTS

A total of 51 patients were enrolled. The incidence of grade ≥ 3 diarrhea was 15.7% (8/51). Other common grade ≥ 3 adverse events were neutropenia, anemia, thrombocytopenia and fatigue were 13.7% (7/51), 5.9% (3/51), 2.0% (1/51) and 5.9% (3/51), respectively. The relative dose intensities of irinotecan, bevacizumab, and S-1 were 80.0, 86.8, and 77.7%, respectively. The median progression-free survival and overall survival were 8.4 months (5.8-9.8) and 17.1 months (11.8-22.3).

CONCLUSIONS

The alternate-day S-1 administration does not have significant effectiveness to reduce diarrhea in patients who received second-line treatment for metastatic colorectal cancer.

Study protocol of a phase II clinical trial (KSCC1501A) examining oxaliplatin + S-1 for treatment of HER2-negative advanced/recurrent gastric cancer previously untreated with chemotherapy

Background

Oxaliplatin + S-1 is a recognized treatment regimen in Japan, but there are no Japanese clinical data on an oxaliplatin dose of 130 mg/m². The current research involves a single-arm, prospective, phase II clinical trial to examine the efficacy and safety of oxaliplatin + S-1 with an oxaliplatin dose of 130 mg/m² to treat HER2-negative advanced/recurrent gastric cancer previously untreated with chemotherapy in Japan.

Methods/design

The primary endpoint of this trial will be the response rate, and the secondary endpoints will be the safety profile of oxaliplatin + S-1, progression-free survival, the response rate in subjects under the age of 75, overall survival, time to treatment failure, duration of treatment, time to failure of strategy, and dose intensity. The threshold response rate is 45% and the expected response rate is 60%. Assuming that a one-tailed score test will be performed with an α of 0.05, 68 patients are needed to ensure a statistical power of 80%. Planned enrollment is 70 subjects and the total duration of this trial is expected to be 3 years.

Discussion

Since replacing cisplatin with oxaliplatin should provide the same level of therapeutic efficacy while limiting adverse events and simplifying treatment, oxaliplatin + S-1 may be increasingly used to treat gastric cancer in Japan. Verifying the efficacy and safety of oxaliplatin + S-1 with an oxaliplatin dose of 130 mg is an important task that the current trial has set out to achieve.

Trial registration

The protocol was registered at the website of the University Hospital Medical Information Network (UMIN), Japan (protocol ID UMIN000017550) on May 29, 2015. The details are available at the following web address: http://www.umin.ac.jp/ctr/.

Phase I study of neoadjuvant chemotherapy with S-1 and oxaliplatin for locally advanced gastric cancer (Neo G-SOX PI)

BACKGROUND

The prognosis of locally advanced gastric cancer, such as clinical T4 disease, bulky nodal involvement, type 4 and large type 3 gastric cancer, remains unsatisfactory, even with D2 gastrectomy followed by adjuvant chemotherapy. One promising approach is neoadjuvant chemotherapy. Combination chemotherapy with S-1 and oxaliplatin (SOX) is recognised as a potentially promising regimen for gastric cancer. However, the use of neoadjuvant chemotherapy consisting of SOX for locally advanced gastric cancer has not been reported. The aim of this study was to determine the maximum tolerated dose (MTD) and recommended dose of preoperative chemotherapy combined with SOX for locally advanced gastric cancer.

METHODS

Patients received two cycles of neoadjuvant chemotherapy with oxaliplatin on day 1, as well as S-1 (80 mg/m²/day, twice daily) for 14 days, repeated every 3 weeks. They then underwent gastrectomy with curative D2/3 lymph node dissection followed by adjuvant S-1 (80 mg/m²/day, twice daily) for 1 year. Escalation of oxaliplatin dose was planned (starting at level 0, oxaliplatin 100 mg/m²; level 1, 130 mg/m²).

RESULTS

Six patients were enrolled. MTD was not reached at level 1. Oxaliplatin 130 mg/m² in combination with S-1 80 mg/m²/day twice daily could be administered with acceptable toxicity. Peripheral neuropathy was observed in all patients but with no functional disorders. No treatment-related death was observed and the incidence of operative morbidity was tolerable. Resection with curative intent was undertaken in all patients with R0 resection performed in five (83%) and R1 in one. Two of the six patients had a pathological complete response (33%).

CONCLUSION

Neoadjuvant chemotherapy with an SOX regimen was feasible in patients with locally advanced gastric cancer. The recommended phase II dose was determined to be oxaliplatin 130 mg/m² in combination with S-1 80 mg/m²/day, twice daily.

A multi-institutional feasibility study of S-1/oxaliplatin plus bevacizumab in patients with advanced/metastatic colorectal cancer: the HiSCO-02 prospective phase II study

PURPOSE

FOLFOX is a standard combination chemotherapy regimen for metastatic colorectal cancer (CRC). 5-Fluorouracil (5-FU) is infused continuously through a pump for 46 h; therefore, replacement of infused 5-FU with oral S-1 would be more convenient for patients. We investigated the efficacy and safety of S-1/oxaliplatin (SOX) plus bevacizumab regimen in a community setting.

METHODS

We conducted a phase II clinical study in Hiroshima, Japan. We enrolled individuals aged 20-80 years who had metastatic CRC, an Eastern Cooperative Oncology Group performance status of 0 or 1, assessable lesions, and not received previous chemotherapy. Eligible patients were administered SOX plus bevacizumab (S-1 80 mg/m²/day, day 1-14 orally; and oxaliplatin 130 mg/m² day 1 i.v., bevacizumab 7.5 mg/kg, day 1 i.v. q3w). The primary endpoint was response rate (RR), and the secondary endpoints were progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

Between May 2011 and January 2014, 55 patients (mean age 64 years) were enrolled at 12 institutions. Median follow up duration was 20.2 months (range 1.3-47.1 months). RR was 47.1 % [95 % confidence interval (CI) 33.7-60.6 %]. Median PFS and OS was 9.2 months (95 % CI 7.6-10.8) and 22.5 months (95 % CI 19.4-25.9), respectively. Major adverse events (grade 3/4) were neutropenia (9.3 %), thrombocytopenia (5.6 %), anorexia (18.5 %), and sensory neuropathy (16.7 %).

CONCLUSION

These data suggested that SOX plus bevacizumab is effective and capable of being managed in metastatic CRC patients in our community clinical practice.

Efficacy and safety of oxaliplatin, bevacizumab and oral S-1 for advanced recurrent colorectal cancer

The aim of this study was to evaluate the efficacy and safety of co-administration of oral S-1 and oxaliplatin (SOX) in combination with bevacizumab (bev) in patients with advanced recurrent colorectal cancer. A retrospective study of 36 patients with advanced recurrent colorectal cancer was performed, of whom 27 received first-line and 9 received second-line SOX+bev chemotherapy between 2010 and 2013 at the Hachioji Digestive Disease Hospital (Hachioji, Japan). The SOX+bev regimen consisted of administration of intravenous oxaliplatin (85 mg/m²) on days 1 and 14, bevacizumab (5 mg/kg) on day 1, and co-administration of oral S-1 twice daily on days 1-14. The drug regimen was repeated every 4 weeks. SOX+bev treatment was associated with a response rate of 45.2%, a disease control rate of 71%, and a median progression-free survival (PFS) and overall survival (OS) of 9.9 and 21.9 months, respectively. Patients who received first-line chemotherapy benefited from treatment in terms of prolonged PFS (13.8 months) and OS (28.2 months). Grade 3/4 adverse events were infrequent and included anaemia, thrombocytopenia, anorexia, diarrhea, sensory neuropathy, increased aspartate aminotransferase level and skin rash. In conclusion, SOX+bev therapy was found to be feasible and safe for patients with advanced and recurrent colorectal cancer.

Role of targeted therapy in metastatic colorectal cancer

Colorectal cancer (CRC) is a significant cause of cancer-related morbidity and mortality all over the world. Improvements of cytotoxic and biologic agents have prolonged the survival in metastatic CRC (mCRC), with a median overall survival of approximately 2 years and more in the past two decades. The biologic agents that have proven clinical benefits in mCRC mainly target vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR). In particular, bevacizumab targeting VEGF and cetuximab and panitumumab targeting EGFR have demonstrated significant survival benefits in combination with cytotoxic chemotherapy in the first-line, second-line, or salvage setting. Aflibercept, ramucirumab, and regorafenib are also used in second-line or salvage therapy. Recent retrospective analyses have shown that KRAS or NRAS mutations were negative predictive markers for anti-EGFR therapy. Based on the evidence from large randomized clinical trials, personalized therapy is necessary for patients with mCRC according to their tumor biology and characteristics. The aim of this paper was to summarize the results of the major randomized clinical trials and highlight the benefits of the molecular targeted agents in patients with mCRC.

Phase 1 study on S-1 and oxaliplatin therapy as an adjuvant after hepatectomy for colorectal liver metastases

of Background Data The effectiveness of adjuvant chemotherapy in patients with stage II/III colorectal cancer has been confirmed in various studies. However, no adjuvant chemotherapy for colorectal liver metastasis (CLM) classified to stage IV has been established. Objectives We conducted a phase 1 study of S-1 and oxaliplatin to determine the recommended dose (RD) in patients with CLM as adjuvant therapy in two institutes. Methods S-1 and oxaliplatin were administered from day 1 to day 14 of a 3-week cycle as a 2-h infusion every 3 weeks, respectively. The initial doses of S-1 and oxaliplatin were fixed to 80 mg/m(2) and 100 mg/m(2), respectively (level 1). We scheduled in the protocol a dose change of S-1 and oxaliplatin to level 2 (S-1: 80 mg/m(2) and oxaliplatin: 130 mg/m(2)) or level 0 (S-1: 65 mg/m(2) and oxaliplatin: 100 mg/m(2)) depending on the incidence of dose-limiting toxicity (DLT) at level 1 in six patients. Results Because DLT occurred in one among the initial six patients at level 1, the doses were increased to level 2 in the next six patients. At level 2, grade 3 leukopenia and neutropenia occurred in one (16.7 %) and two (33.3 %) patients, respectively, in the absence of non-hematological event. Because no DLT occurred at level 2, we suggest that the RD can be set to the level 2 dose. The median number of cycles delivered at RD was 8. The mean relative dose intensity of S-1 and oxaliplatin at RD was 0.90 and 0.63, respectively. Conclusion In a patient undergoing hepatectomy for CLM, 80 mg/m(2) of S-1 and 130 mg/m(2) of oxaliplatin are recommended as adjuvant therapy. A further study is required to confirm the efficacy and safety of this regimen on a larger scale.

The short-term outcomes of induction SOX (S-1 + oxaliplatin) ± cetuximab chemotherapy followed by short-course chemoradiotherapy in patients with poor-risk locally advanced rectal cancer

PURPOSE

To evaluate the safety and efficacy of induction SOX (S-1 + oxaliplatin) ± cetuximab chemotherapy followed by short-course chemoradiotherapy and surgery in patients with poor-risk locally advanced rectal cancer.

METHODS

We enrolled eligible patients with poor-risk rectal cancer defined as T3 lower rectal cancer with mesorectal fascia involvement, T4a or T4b tumors or cases with lateral lymph node swelling. The primary endpoint was a pathological complete response (pCR), and the secondary endpoints were the objective response rate (ORR) and the pathological high response rate (Grade 2 plus 3).

RESULTS

Twenty eligible patients were enrolled. The majority (75.0 %, 15/20) of the patients completed four cycles of induction chemotherapy, and all patients completed the radiotherapy (25 Gy/10 fractions/5 days). The global rate of Grade 3-4 toxicities was 30.0 % (6/20 patients). The ORRs were 85.0 % (17/20) and 95.0 % (19/20) in the patients who underwent R0 and R1 resection, respectively. The pathological high response rate was 70.0 % (14/20) and the pCR was 10.0 % (2/20).

CONCLUSION

The regimen of induction SOX (S-1 + oxaliplatin) ± cetuximab chemotherapy followed by short-course chemoradiotherapy is safe and is associated with good tumor regression in patients with poor-risk locally advanced rectal cancer.

Effect of pH adjustment by mixing steroid for venous pain in colorectal cancer patients receiving oxaliplatin through peripheral vein: a multicenter randomized phase II study (APOLLO)

PURPOSE

The aim of this phase II clinical trial was to evaluate the preventive effect of dexamethasone mixing injection for venous pain in patients with colorectal cancer during chemotherapy.

MATERIALS AND METHODS

Patients were randomized to receive a 2-h intravenous infusion of oxaliplatin 130 mg/m(2) on day 1 followed by capecitabine 1000 mg/m(2) (or S-1 40-60 mg/m(2)) twice daily on days 1 through 14 of every 3 weeks with or without dexamethasone 1.65 mg at the infusion on day 1.

RESULTS

A total of 53 patients were enrolled. The analysis population consisted of 49 patients (arm A, with dexamethasone N = 24; arm B, without dexamethasone N = 25). The incidence of venous pain ≥grade 2 based on the CTCAE version 4.0 was 33.3 % in arm A and 56.0 % in arm B (relative risk 0.60; 95 % CI 0.31-1.16). The incidences based on the verbal rating scale for arms A and B were 50.0 and 64.0 %, respectively (relative risk 0.78; 95 % CI 0.48-1.28).

CONCLUSION

The primary endpoint was not met in this preliminary study.

A Muti-center, Randomized Phase II Study of Oxaliplatin and S-1 versus Capecitabine and Oxaliplatin in Patients with Metastatic Colorectal Cancer

Background: Capecitabine plus oxaliplatin (XELOX) is considered one of the primary chemotherapy regimens for patients with metastatic colorectal cancer (CRC). Oxaliplatin plus S-1 (OS) has also demonstrated significant efficacy in CRC. We performed this randomized phase II study to evaluate the efficacy and toxicity of XELOX versus OS as first-line chemotherapy in patients with metastatic CRC.

Methods: Patients were assigned randomly to receive either OS or XELOX chemotherapy. Oxaliplatin was administered intravenously to all patients at a dose of 130 mg/m² on day 1. Patients received either S-1 (40 mg/m²) or capecitabine (1,000 mg/m²), twice a day for 2 weeks, followed by a 1-week rest.

Results: Forty-two patients were assigned to the OS arm and 44 to the XELOX arm. The overall response rate was 33.3% (95% CI, 18.8-47.2) in the OS arm and 40.9% (95% CI, 25.5-54.4) in the XELOX arm (P = 0.230). The disease control rate was significantly higher in the OS arm than the XELOX arm [92.9% (95% CI, 83.7-100) versus 77.3% (95% CI, 64.5-89.4), P = 0.044]. With a median follow up of 17.9 months, the median progression-free survival was 6.1 months in the OS arm and 7.4 months in the XELOX arm, respectively (P = 0. 599). The median survival time was 18.7 months in the OS arm and 20.1 months in the XELOX arm (P = 0.340). The most common grade 3/4 hematologic toxicity was thrombocytopenia in both arms (19.0% for OS and 28.6% for XELOX). Grade 3/4 neutropenia was observed more frequently in the XELOX arm than the OS arm (16.7% vs. 2.4%, P = 0.026).

Conclusion: Both OS and XELOX were effective and well tolerated in patients with metastatic CRC. Our results indicate that the combination of oxaliplatin and S-1 is a possible additional therapeutic strategy for such patients.

The SOFT trial: a Phase III study of the dihydropyrimidine dehydrogenase inhibitory fluoropyrimidine S-1 and oxaliplatin (SOX) plus bevacizumab as first-line chemotherapy for metastatic colorectal cancer

ABSTRACT 

A combination of oxaliplatin, leucovorin and 5-fluorouracil (FOLFOX) plus bevacizumab has been widely used for the first-line chemotherapy of metastatic colorectal cancer (mCRC). S-1 is an oral fluoropyrimidine preparation that combines tegafur, a prodrug of 5-fluorouracil, with two modulators. Several studies of combination chemotherapy with oxaliplatin plus S-1 (SOX) conducted in Asia have reported promising efficacy and safety in patients with mCRC, suggesting the potential to replace mFOLFOX6. The SOFT trial (JapicCTI-090699) was a randomized Phase III trial designed to evaluate the noninferiority of SOX plus bevacizumab to mFOLFOX6 plus bevacizumab in patients with mCRC. This review summarizes the drug concept of S-1 and the results of clinical trials of S-1 and SOX in CRC and presents an overview of the SOFT trial.

Randomised phase II trial of S-1 plus oxaliplatin vs S-1 in patients with gemcitabine-refractory pancreatic cancer

Background:

This randomised, open-label, multicenter phase II study compared progression-free survival (PFS) of S-1 plus oxaliplatin (SOX) with that of S-1 alone in patients with gemcitabine-refractory pancreatic cancer.

Methods:

Patients with confirmed progressive disease following the first-line treatment with a gemcitabine-based regimen were randomised to receive either S-1 (80/100/120 mg day⁻¹ based on body surface area (BSA), orally, days 1–28, every 6 weeks) or SOX (S-1 80/100/120 mg day⁻¹ based on BSA, orally, days 1–14, plus oxaliplatin 100 mg m⁻², intravenously, day 1, every 3 weeks). The primary end point was PFS.

Results:

Between January 2009 and July 2010, 271 patients were randomly allocated to either S-1 (n=135) or SOX (n=136). Median PFS for S-1 and SOX were 2.8 and 3.0 months, respectively (hazard ratio (HR)=0.84; 95% confidence interval (CI), 0.65–1.08; stratified log-rank test P=0.18). Median overall survival (OS) was 6.9 vs 7.4 months (HR=1.03; 95% CI, 0.79–1.34; stratified log-rank test P=0.82). The response rate (RR) was 11.5% vs 20.9% (P=0.04). The major grade 3/4 toxicities (S-1 and SOX) were neutropenia (11.4% and 8.1%), thrombocytopenia (4.5% and 10.3%) and anorexia (12.9% and 14.7%).

Conclusions:

Although SOX showed an advantage in RR, it provided no significant improvement in PFS or OS compared with S-1 alone.

A phase I dose escalation study of oxaliplatin plus oral S-1 and pelvic radiation in patients with locally advanced rectal cancer (SHOGUN trial)

Background

The objective of this phase I study was to determine the maximum tolerated dose (MTD) and recommended dose (RD) of preoperative chemoradiotherapy (CRT) with S-1 plus oxaliplatin in patients with locally advanced rectal cancer.

Methods

Patients received radiotherapy in a total dose of 50.4 Gy in 28 fractions. Concurrent chemotherapy consisted of a fixed oral dose of S-1 (80 mg/m²/day) on days 1–5, 8–12, 22–27, and 29–33, plus escalated doses of oxaliplatin as an intravenous infusion on days 1, 8, 22, and 29. Oxaliplatin was initially given in a dose of 40 mg/m²/week to three patients. The dose was then increased in a stepwise fashion to 50 mg/m²/week and the highest dose level of 60 mg/m²/week until the MTD was attained.

Results

Thirteen patients were enrolled, and 12 received CRT. Dose-limiting toxicity (DLT) occurred in two of six patients (persistent grade 2 neutropenia, delaying oxaliplatin treatment by more than 3 days) at dose level 3; there were no grade 3 or 4 adverse events defined as DLT. The RD was 60 mg/m²/week of oxaliplatin on days 1, 8, 22, and 29. Twelve patients underwent histologically confirmed R0 resections, and two out of six patients (33%) given dose level 3 had pathological complete responses.

Conclusions

The RD for further studies is 80 mg/m² of S-1 5 days per week plus 60 mg/m² of oxaliplatin on days 1, 8, 22, and 29 and concurrent radiotherapy. Although our results are preliminary, this new regimen for neoadjuvant chemoradiotherapy is considered safe and active.

Trial registration

This trial was registered with Clinicaltrials.gov (identifier: NCT01227239).

S-1 plus oxaliplatin versus capecitabine plus oxaliplatin for the first-line treatment of patients with metastatic colorectal cancer: updated results from a phase 3 trial

Background

We report updated progression-free survival (PFS) and overall survival (OS) data from a trial that compared capecitabine plus oxaliplatin (CapeOX) versus S-1 plus oxaliplatin (SOX) for the first-line treatment of metastatic colorectal cancer.

Methods

This trial was a randomized, two-armed, non-inferiority phase 3 comparison of CapeOX (capecitabine 1000 mg/m2 twice daily on days 1–14 and oxaliplatin 130 mg/m2 on day 1) versus SOX (S-1 40 mg/m2 twice daily on days 1–14 and oxaliplatin 130 mg/m2 on day 1). The primary end point was to show non-inferiority of SOX relative to CapeOX in terms of PFS. Thus, a follow-up exploratory analysis of PFS and OS was performed.

Results

The intention to treat (ITT) population was comprised of 340 patients (SOX arm: 168 and CapeOX arm: 172). The updated median PFS was 7.1 months (95% CI 6.4-8.0) in the SOX group and 6.3 months (95% CI 4.9-6.7) in the CapeOX group (hazard ratio [HR], 0.83 [0.66-1.04], p = .10). The median OS was 19.0 months (95% CI 15.3-23.0) in the SOX group and 18.4 months (95% CI 14.1-20.7) in the CapeOX group (HR, 0.86 [0.68-1.08], p = .19). Subgroup analyses according to principal demographic factors such as sex, age, ECOG (Eastern Cooperative Oncology Group) performance status, primary tumor location, measurability, previous adjuvant therapy, number of metastatic organs, and liver metastases showed no interaction between any of these characteristics and the treatment.

Conclusions

Updated survival analysis shows that SOX is similar to CapeOX, confirming the initial PFS analysis. Therefore, the SOX regimen could be an alternative first-line doublet chemotherapy strategy for patients with metastatic colorectal cancer.

Trial registration

NCT00677443 and May 12 2008

Efficacy of S-1 in colorectal cancer

INTRODUCTION

S-1 is an oral fluoropyrimidine that consists of tegafur, 5-chloro-2, 4-dihydroxypyridine and potassium oxonate. It has been developed as a prodrug of 5-fluorouracil with the goal of improving therapeutic efficacy and tolerability.

AREAS COVERED

This review aims to provide an evidence-based update of clinical trials that have investigated the clinical efficacy, adverse-event profile, dosage and administration of S-1, given alone or in combination with conventional chemotherapeutics and new target-oriented drugs, in the management of colorectal cancer (CRC). Additionally, differences in the tolerability and pharmacokinetics of S-1 between Caucasians and Asians have been described. Finally, the therapeutic efficacy of S-1 regarding metastatic CRC or postoperative CRC has been discussed. Available data have stimulated further research, including Phase III trials for the treatment of advanced CRC.

EXPERT OPINION

Treatment using S-1 combined with oxaliplatin (± bevacizumab) and irinotecan has achieved promising results in terms of feasibility, safety and effectiveness. Furthermore, S-1 is an acceptable treatment as adjuvant chemotherapy for colon cancer.

Safety and pharmacokinetics of S-1 in a recurrent colon cancer patient with chronic myeloid leukemia treated with dasatinib: a case report

PURPOSE

The safety of S-1 in recurrent colorectal cancer patients with chronic myeloid leukemia (CML) treated with dasatinib has not been established. We evaluated the safety and pharmacokinetics of S-1 in a recurrent colon cancer patient with CML treated with dasatinib.

PATIENT

A 70-year-old man had undergone surgery three times for sigmoid colon cancer and recurrence. Systemic chemotherapy with S-1 plus oxaliplatin plus bevacizumab as a clinical trial had already been administered because of metastatic colon cancer. The patient's medical history was CML, and he had been receiving dasatinib treatment (100 mg once daily). Based on the diagnosis of unresectable and multiple metastases, S-1 monotherapy was started. S-1 (120 mg/day) was taken for 28 consecutive days, followed by a 14-day rest. Blood samples were obtained before and after the first administration of S-1. The plasma pharmacokinetics of S-1 were comparable to a pharmacokinetics study of S-1.

RESULTS

The area under the plasma concentration-time curve (AUC0-8) of tegafur (FT), 5-chloro-2, 4-dihydroxypyridine (CDHP), oxonate (Oxo), and 5-fluorouracil (5-FU) was 4,309.2, 716.3, 86.8, and 492.75 ng h/mL, respectively, after S-1 administration. The pharmacokinetics of FT, CDHP, Oxo, and 5-FU after treatment with S-1 were not significantly different from a phase I pharmacokinetics study of S-1. During treatment with S-1 and dasatinib, CML relapse and serious myelosuppression were not observed.

CONCLUSIONS

Our report suggests that S-1 is an important treatment option for recurrent colorectal cancer in patients with CML treated with dasatinib.

Irinotecan Plus S-1 Followed by Hepatectomy for a Patient with Initially Unresectable Colorectal Liver Metastases, Who Showed Severe Drug Rash with Oxaliplatin Plus 5-FU and Leucovorin (FOLFOX)

For unresectable colorectal liver metastases (CRLM), hepatic resection with or without chemotherapy is the only curative treatment that sufficiently achieves long-term survival. However, occasional severe allergic responses to anticancer drugs necessitate treatment discontinuation. A 45-year-old woman presented with metachronous unresectable colorectal liver metastases. Chemotherapy with oxaliplatin plus 5-FU and leucovorin (FOLFOX) was initiated, but severe allergic dermatitis developed after the second cycle. Although she reported no prior history of adverse reactions to tegafur-uracil, a drug lymphocyte stimulation test showed an allergic response to 5-FU. We subsequently replaced with Irinotecan plus S-1 (IRIS) chemotherapy which was well tolerated and resulted in a partial response after 3 cycles. As a result, right trisectionectomy was successfully performed and no recurrence was detected in the following 3 years. A severe allergic reaction to intravenous 5-FU-containing drug regimens can be successfully alleviated by switching to S-1-containing regimens such as IRIS or S-1 plus oxaliplatin (SOX).

Gimeracil and oteracil porassium capsules as a single drug in adjuvant treatment of patients with advanced colorectal cancer: A randomized clinical study

AIM: To evaluate the efficacy and safety of gimeracil and oteracil porassium capsules (S-1) as a single drug in the adjuvant treatment of patients with advanced colorectal cancer.

METHODS: Eligible patients with advanced colorectal cancer were randomly assigned to either a control group or an experimental group. The patients of the control group received routine symptomatic treatment, while the experimental group was additionally given S-1 [60 mg/(m²•d), bid, P.O. on days 1-14, then drug withdrawal for 1 wk, repeated every 3 wk, stopped until disease progression or unacceptable toxicity occurred] beside the routine symptomatic treatment.

RESULTS: A total of 83 eligible patients were enrolled, including 4 in the control group and 41 in the experimental arm. Median follow-up period was 54 wk. The baseline characteristics were comparable between the two groups. S-1 treatment improved the progression-free survival (PFS), though there was no statistical difference (HR = 0.52, 95%CI: 0.22-1.23, P = 0.1384). For all patients with advanced colorectal cancer, the 1-year PFS for the control arm and experimental arm was 78.6% and 97.6%, respectively, favoring the S-1 regimen. For patients with advanced colon cancer, the improvement of PFS did not differ significantly between the two arms (HR = 0.62, 95%CI: 0.20-1.95, P = 0.4156). The 1-year PFS for the control arm and experimental arm was 76.2% and 95.0%, favoring the S-1 regimen. For patients with advanced rectal cancer, the improvement of PFS did not differ significantly between the two arms (HR = 0.42, 95%CI: 0.11-1.58, P = 0.2005). The 1-year PFS for the control arm and experimental arm was 76.2% and 95.2%, respectively. Three cases developed S-1-induced adverse reactions, including one case of grade Ⅱ and two cases of grade Ⅰ, which, however, did not cause treatment discontinuation.

CONCLUSION: S-1 can improve the PFS in patients with advanced colorectal cancer, indicating that such patients may benefit from S-1 regimen in the adjuvant setting.

A phase I trial of preoperative S-1 in combination with oxaliplatin and pelvic radiation for lower rectal cancer with T4 and lateral pelvic lymph node metastasis

BACKGROUND

The purpose of this phase I study of the dose escalation of oxaliplatin in combination with oral S-1 and pelvic radiation preoperatively for poor-risk lower rectal cancer was to determine the dose-limiting toxicity (DLT) and recommended dose of oxaliplatin.

METHODS

Patients with cT4 and lateral pelvic lymph node metastasis, and without distant metastasis (cM0), were treated with weekly oxaliplatin, oral S-1 40 mg/m(2) twice daily for 5 days a week, and radiation. A total of 5 weekly doses of oxaliplatin were planned. RT was administered to a total dose of 50.4 Gy in 28 fractions.

RESULTS

We enrolled 11 patients between December 2009 and January 2012. DLTs were observed at dose level 1 (50 mg/m(2)) in two patients, one of whom experienced grade 3 aspartate aminotransferase elevation and a grade 3 alanine aminotransferase increase, and the other developed grade 4 hypokalemia and a grade 3 alanine aminotransferase increase. Five patients at dose level 2 (60 mg/m(2)) showed no DLTs. The hematological toxicities in all patients were mild and reversible. One patient showed distant metastasis after chemoradiation. Ten of the 11 patients achieved R0 resection by mesorectal resection and lateral lymph node dissection; three of the 10 underwent combined resection of the other organs.

CONCLUSION

This phase I trial of preoperative S-1 in combination with oxaliplatin and radiation for lower rectal cancer with T4 and lateral pelvic lymph node metastasis revealed that the recommended dose of oxaliplatin was 60 mg/m(2) weekly.

A phase II open-label randomized multicenter trial of TSU-68 in combination with S-1 and oxaliplatin versus S-1 in combination with oxaliplatin in patients with metastatic colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is the fourth leading cause of cancer-related deaths worldwide. The combination of oxaliplatin-based treatments (oxaliplatin plus infusional 5-fluorouracil and leucovorin [FOLFOX] or oxaliplatin plus capecitabine [CapeOX]) and bevacizumab is a standard chemotherapy regimen for metastatic CRC (mCRC). However, several clinical studies that tested S-1 plus oxaliplatin (SOX) indicate that SOX is also a treatment option for mCRC. TSU-68 is an oral compound that inhibits vascular endothelial growth factor receptor and platelet-derived growth factor receptor. The recommended dose of TSU-68 + SOX was previously determined in a phase I study of mCRC patients. The goal of this trial was to evaluate the efficacy of TSU-68 in combination with SOX.

METHODS

This open-label multicenter randomized phase II trial was performed in Korea. Treatment-naive mCRC patients with a performance status of 0 or 1 were randomized in a 1:1 ratio to receive either TSU-68 + SOX or SOX alone. The primary endpoint was progression-free survival (PFS).

RESULTS

A total of 105 patients (TSU-68 + SOX, 52 patients; SOX alone, 53 patients) were randomized. The median PFS was 7.0 months in the TSU-68 + SOX group (hazard ratio [HR], 1.057) and 7.2 months in the SOX group (p = 0.8401). The most frequent grade 3 and 4 adverse events were thrombocytopenia (9.6 % [TSU-68 + SOX] vs. 26.4 % [SOX]), neutropenia (13.5 % [TSU-68 + SOX] vs. 15.1 % [SOX]), and anemia (3.8 % [TSU-68 + SOX] vs. 13.2 % [SOX]). We observed a difference between the 2 groups for all grades of anemia (15.4 % [TSU-68 + SOX] vs. 32.1 % [SOX]), diarrhea (30.8 % [TSU-68 + SOX] vs. 47.2 % [SOX]), vomiting (50.0 % [TSU-68 + SOX] vs. 26.4 % [SOX]), and chromaturia (23.1 % [TSU-68 + SOX] vs. 0.0 % [SOX]). Analysis using a Cox proportional hazard model showed that baseline interleukin 6 (IL-6) levels were associated with a survival benefit of TSU-68 (p = 0.012).

CONCLUSION

TSU-68 + SOX had a favorable safety profile. However, TSU-68 did not have a synergistic effect on the efficacy of SOX. The baseline serum IL-6 level could be a prognostic factor for TSU-68 efficacy.

Leucovorin, fluorouracil, and oxaliplatin plus bevacizumab versus S-1 and oxaliplatin plus bevacizumab in patients with metastatic colorectal cancer (SOFT): an open-label, non-inferiority, randomised phase 3 trial

BACKGROUND

Studies done in Asia have shown that a regimen of S-1 plus oxaliplatin (SOX) has promising efficacy and safety in patients with metastatic colorectal cancer. We aimed to establish whether SOX plus bevacizumab is non-inferior to mFOLFOX6 (modified regimen of leucovorin, fluorouracil, and oxaliplatin) plus bevacizumab as first-line chemotherapy for metastatic colorectal cancer.

METHODS

We undertook an open-label, non-inferiority, randomised phase 3 trial in 82 sites in Japan. We enrolled individuals aged 20-80 years who had metastatic colorectal cancer, had an Eastern Cooperative Oncology Group performance status of 0 or 1, had assessable lesions, had received no previous chemotherapy or radiotherapy, could take drugs orally, and had adequate organ function. Eligible patients were randomly assigned (1:1) to receive either mFOLFOX6 plus bevacizumab (on day 1 of each 2-week cycle, 5 mg/kg intravenous infusion of bevacizumab and a simultaneous intravenous infusion of 85 mg/m(2) oxaliplatin, 200 mg/m(2)l-leucovorin, 400 mg/m(2) bolus fluorouracil, and 2400 mg/m(2) infusional fluorouracil) or SOX plus bevacizumab (on day 1 of each 3-week cycle, 7·5 mg/kg intravenous infusion of bevacizumab and 130 mg/m(2) intravenous infusion of oxaliplatin; assigned dose of S-1 twice a day from after dinner on day 1 to after breakfast on day 15, followed by 7-day break). Randomisation was done centrally with the minimisation method, with stratification by institution and whether postoperative adjuvant chemotherapy had been given. Participants, investigators, and data analysts were not masked to treatment assignment. The primary endpoint was progression-free survival (PFS), which was defined as the interval between enrolment and progressive disease (≥20% increase in sum of longest dimensions of target lesions from baseline, or appearance of new lesions) or death, whichever came first. The primary analysis was done by modified intention to treat. This trial is registered with the Japan Pharmaceutical Information Center, number JapicCTI-090699.

FINDINGS

Between Feb 1, 2009, and March 31, 2011, 512 patients underwent randomisation. 256 patients assigned to receive SOX plus bevacizumab and 255 assigned to receive mFOLFOX6 plus bevacizumab were included in the primary analysis. Median PFS was 11·5 months (95% CI 10·7-13·2) in the group assigned to mFOLFOX6 plus bevacizumab and 11·7 months (10·7-12·9) in the group assigned to SOX plus bevacizumab (HR 1·04, 95% CI 0·86-1·27; less than non-inferiority margin of 1·33, pnon-inferiority=0·014). The most common haematological adverse events of grade 3 or higher were leucopenia (21 [8%] of 249 patients given mFOLFOX6 plus bevacizumab included in safety analysis vs six [2%] of 250 given SOX plus bevacizumab; p=0·0029) and neutropenia (84 [34%] vs 22 [9%]; p<0·0001). Grade 3 or higher anorexia (13 [5%] vs three [1%]; p=0·019) and diarrhoea (23 [9%] vs seven [3%]; p=0·0040) were significantly more common in patients given SOX plus bevacizumab than in those given mFOLFOX6 plus bevacizumab. We recorded seven treatment-related deaths (three in the group given mFOLFOX6 plus bevacizumab; four in that given SOX plus bevacizumab).

INTERPRETATION

SOX plus bevacizumab is non-inferior to mFOLFOX6 plus bevacizumab with respect to PFS as first-line treatment for metastatic colorectal cancer, and could become standard treatment in Asian populations.

FUNDING

Taiho.

Dose-finding study on adjuvant chemotherapy with S-1 plus oxaliplatin for gastric cancer

Gastric cancer (GC) is the fourth most common type of cancer, accounting for an estimated one million new cases annually worldwide. Locally advanced GC often recurs, even following curative surgical resection. Therefore, there is a need for an effective adjuvant chemotherapy regimen. The aim of this trial was to investigate the maximum tolerated dose (MTD) of S-1 when administered in combination with oxaliplatin in postoperative GC patients. Oxaliplatin was administered at a fixed dose of 130 mg/m² on day 1. S-1 was administered from day 1 to 14 of a 3-week cycle and escalated by 10 mg/m²/day from 60 to 80 mg/m²/day. A total of 15 patients were enrolled in this study. No dose-limiting toxicities (DLTs) occurred at level 1 (S-1, 60 mg/m²; n=3). One case of DLT (grade 3 vomiting) occurred at level 2 (S-1, 70 mg/m²; n= 6), whereas 2 cases of grade 3 vomiting were observed at level 3 (S-1, 80 mg/m²; n=6). Based on these results, the MTD of S-1 was initially determined to be 70 mg/m². Furthermore, we observed that cytochrome P450 2A6 (CYP2A6) 41349640C>G was associated with severe neutropenia (C/C vs. C/G vs. G/G = 0 vs. 33.33 vs. 100%; P=0.03297, Fisher's exact test) during the entire course of the treatment.

A retrospective study of S-1 and oxaliplatin combination chemotherapy in patients with refractory pancreatic cancer

PURPOSE

The aim of this study was to evaluate S-1 and oxaliplatin combination chemotherapy (SOX) in patients with refractory pancreatic cancer (PC).

METHODS

Consecutive patients with advanced PC refractory to gemcitabine who were treated with oral S-1 (80 mg/m²) on days 1-14 and intravenous oxaliplatin (100 mg/m²) on day 1 every 3 weeks were studied retrospectively. The primary end point was the objective response rate (ORR). The secondary end points were progression-free survival (PFS), overall survival (OS), the disease control rate (DCR), and safety.

RESULTS

Between March 2009 and October 2011, 30 patients were treated with SOX, with a median of two courses (range 1-8). The ORR and DCR were 10.0 and 50.0 %, respectively. Median PFS and OS were 3.4 months (95 % confidence interval [CI] 1.3-5.3) and 5.0 months (95 % CI 3.4-7.4), respectively. The median PFS and OS were 5.6 and 9.1 months in patients receiving S-1 and oxaliplatin as a second-line treatment. Major grade 3 or 4 adverse events included neutropenia (10.0 %), anemia (3.3 %), and diarrhea (6.7 %).

CONCLUSIONS

SOX was well tolerated and moderately effective in patients with refractory PC.

Complete Response of Para-Aortic and Lateral Pelvic Lymph Node Recurrence of Rectal Cancer Treated to S-1 Monotherapy

This report presents a case of para-aortic and lateral pelvic lymph node recurrence of rectal cancer that showed complete response to S-1 monotherapy. A 69-year-old man underwent low anterior resection for rectal cancer in 2007. Para-aortic lymph and right lateral pelvic lymph node recurrence occurred in 2008. He received a fluorouracil/folinic acid plus oxaliplatin regimen; however, G4 neutropenia and G3 fatigue were experienced. We started S-1 monotherapy as a salvage treatment. Abdominal computed tomography did not reveal any para-aortic and lateral pelvic lymph nodes recurrence after 10 cycles of S-1 monotherapy. Hence, response in this case was classified as a complete response. No recurrence was noted 36 months after the complete response. S-1 monotherapy is likely to be effective in treating patients with metastatic colorectal cancer who do not respond to standard combination chemotherapy.

Abrogation of the accelerated blood clearance phenomenon by SOXL regimen: promise for clinical application

We recently proposed an S-1 combined with oxaliplatin (SOXL) regimen, a combination treatment consisting of oral metronomic S-1 dosing and intravenous administration of oxaliplatin (l-OHP) containing PEGylated liposomes, which showed potent antitumor activity in vivo. PEGylated liposomes induce what is referred to as the "accelerated blood clearance (ABC) phenomenon" upon repeated administration and consequently lose their long-circulating characteristics. This phenomenon seems to pose an impediment for the clinical application and use of PEGylated liposomal formulations. In the present study, l-OHP-containing PEGylated liposomes in the SOXL regimen significantly attenuated the ABC phenomenon in a dose-dependent manner through suppression of the anti-PEG IgM response, which allowed an enhanced hepatic uptake of subsequently injected test PEGylated liposomes. In tumor-bearing mice, the abrogation of the ABC phenomenon restored intratumor accumulation of subsequently injected PEGylated liposomes. Consequently, the therapeutic efficacy of the SOXL regimen over the combination of the free form of the drugs was credited not only with the selective delivery of drugs to the tumor tissue but also with ensuring an adequate accumulation of subsequent doses within the tumor tissue. The SOXL regimen we proposed may hold promise as a safe and effective treatment regimen for advanced colorectal cancer.

S-1 plus oxaliplatin versus capecitabine plus oxaliplatin for first-line treatment of patients with metastatic colorectal cancer: a randomised, non-inferiority phase 3 trial

BACKGROUND

Capecitabine plus oxaliplatin (CapeOX) is one of the reference doublet cytotoxic chemotherapy treatments for patients with metastatic colorectal cancer. We aimed to compare the efficacy and safety of CapeOX with that of S-1 plus oxaliplatin (SOX), a promising alternative treatment for patients with metastatic colorectal cancer.

METHODS

In this open-label, multicentre, randomised phase 3 trial, we randomly assigned patients (1:1) from 11 institutions in South Korea to receive either CapeOX (capecitabine 1000 mg/m(2) twice daily on days 1-14 and oxaliplatin 130 mg/m(2) on day 1) or SOX (S-1 40 mg/m(2) twice daily on days 1-14 and oxaliplatin 130 mg/m(2) on day 1). Treatment was repeated every 3 weeks and continued for as many as nine cycles of oxaliplatin-containing chemotherapy, except in instances of disease progression, unacceptable toxicity, or a patient's refusal. Maintenance chemotherapy with S-1 or capecitabine was allowed after discontinuation of oxaliplatin. Randomisation was done with a computer-generated sequence (stratified by primary sites, previous adjuvant or neoadjuvant treatment, and the presence of measurable lesions). The primary endpoint was to show non-inferiority of SOX relative to CapeOX in terms of progression-free survival (PFS). The primary analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00677443.

FINDINGS

Between May 14, 2008, and Sept 23, 2009, we randomly assigned 168 patients to receive SOX and 172 to receive CapeOX. Median PFS was 8·5 months (95% CI 7·6-9·3) in the SOX group and 6·7 months (6·2-7·1) in the CapeOX group (hazard ratio, 0·79 [95% CI 0·60-1·04]; p(non-inferiority)<0·0001, p(log-rank)=0·09). The upper limit of the CI was below the predefined margin of 1·43, showing the non-inferiority of SOX to CapeOX. We recorded a higher incidence of grade 3-4 neutropenia (49 [29%] vs 24 [15%]), thrombocytopenia (37 [22%] vs 11 [7%]), and diarrhoea (16 [10%] vs seven [4%]) in the SOX group than in the CapeOX group. The frequency of any grade of hand-foot syndrome was greater in the CapeOX group than it was in the SOX group (51 [31%] vs 23 [14%]).

INTERPRETATION

The SOX regimen could be an alternative first-line doublet chemotherapy strategy for patients with metastatic colorectal cancer. Further investigation is needed to explore its potential when used together with other targeted agents or as adjuvant chemotherapy.

FUNDING

Korea Healthcare Technology Research and Development Project, Ministry of Health and Welfare, South Korea.

S-1 for the treatment of gastrointestinal cancer

INTRODUCTION

5-Fluorouracil (5-FU)-based regimens are used worldwide as the standard treatment in chemotherapy for gastric cancer. S-1 , a fourth-generation oral fluoropyrimidine that combines tegafur and two biochemical modulators: gimeracil and oteracil potassium, is now attracting considerable interest.

AREAS COVERED

This review addresses the clinical evidence of S-1 in gastrointestinal malignancies, such as gastric, colorectal, pancreatic and biliary tract cancers. S-1 has demonstrated advantages over standard therapies, in both advanced and postoperative settings, in large Phase III studies. S-1 alone or S-1 plus cisplatin is recommended in the 2010 Gastric Cancer Treatment Guidelines, by the Japanese Gastric Cancer Association. Results from Phase III studies have demonstrated that S-1 in combination with chemotherapies, such as cisplatin in gastric cancer, and irinotecan and oxaliplatin in colorectal cancers, is non-inferior to conventional 5-FU-based standard regimens, with the benefit of convenience and reduced toxicity.

EXPERT OPINION

The excellent design of S-1 aimed to reduce toxicity by avoiding certain routes of degradation, and to enhance activity by reducing catabolism. This has provided not only a suitable alternative to 5-FU, but also higher efficacy.

A randomized phase II trial of S-1-oxaliplatin versus capecitabine-oxaliplatin in advanced gastric cancer

PURPOSE

S-1 or capecitabine plus oxaliplatin are considered active and tolerable in gastric cancer patients. We conducted a randomized phase II trial in gastric cancer patients to compare the activity and safety of these combinations.

METHODS

The patients received S-1 at 80 mg/m2 for 14 days, followed by a 7-day rest period within a 3-week schedule in the S-1/oxaliplatin (SOX) arm, and capecitabine at 2000 mg/m2 for 14 days, followed by a 7-day rest period within a 3-week schedule in the capecitabine/oxaliplatin (CAPOX) arm. Oxaliplatin 130 mg/m2 was administered every 3 weeks in both arms.

RESULTS

One hundred twenty-nine patients were randomly assigned to SOX (N=65) or CAPOX (N=64). The median time to progression and the overall survival were 6.2 and 12.4 months with SOX, respectively; and 7.2 and 13.3 months with CAPOX, respectively. The overall response rates were 40% and 44% for SOX and CAPOX, respectively. The most frequent grade 3 or 4 toxicities were thrombocytopenia (15.4%) for SOX and neutropenia (18.8%) for CAPOX. The median time to 10% deteriorations in global health scores was similar in both arms (SOX, 4.3 months, CAPOX, 4.9 months).

CONCLUSION

Both the SOX and CAPOX regimens were equally active and well tolerated in advanced gastric cancer patients.

Phase I study of two schedules of oral S-1 in combination with fixed doses of oxaliplatin and bevacizumab in patients with advanced solid tumors

BACKGROUND

S-1 is a novel oral agent combining the 5-fluorouracil (FU) prodrug tegafur with gimeracil and oteracil, which inhibit 5-FU degradation by dihydropyrimidine dehydrogenase and phosphorylation within the gastrointestinal tract, respectively. The study was designed to identify the maximum tolerable dose and the dose-limiting toxicities of two schedules of S-1 combined with oxaliplatin and bevacizumab, in advanced solid tumor patients.

METHODS

Schedule A: S-1 was administered orally at 20 mg/m(2) twice daily for 14 consecutive days, escalated by 5 mg/m(2), with fixed-dose intravenous bevacizumab 7.5 mg/kg and oxaliplatin 130 mg/m(2) on day 1 of each 3-week cycle. Schedule B: S-1 was administered at 25 mg/m(2) twice daily for 7 consecutive days, escalated by 5 mg/m(2), with fixed-dose intravenous bevacizumab 5 mg/kg and oxaliplatin 85 mg/m(2) on day 1 of each 2-week cycle.

RESULTS

The maximum tolerated dose and recommended phase II dose of S-1 was 25 mg/m(2) twice daily for 14 days for schedule A and 35 mg/m(2) twice daily for 7 days for schedule B. The most common dose-limiting toxicities were grade 3 diarrhea. Both regimens were well tolerated. No pharmacokinetic interactions between oxaliplatin and S-1 components were observed.

CONCLUSIONS

S-1, oxaliplatin and bevacizumab can be administered with acceptable safety and tolerability and without evidence of pharmacokinetic interactions.