Synergistic antitumor activity of capecitabine in combination with irinotecan

A phase 1b study of OXIRI in pancreatic adenocarcinoma patients and its immunomodulatory effects

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal and debilitating disease with limited therapeutic options. The aim of this clinical study was to evaluate the safety, efficacy and pharmacokinetics of a novel regimen comprised of metronomic oxaliplatin (O), chronomodulated capecitabine (X) and UGT1A1 genotype-guided dosing of irinotecan (IRI) [OXIRI] as well as its immunomodulatory effects. Thirty-six patients were enrolled into either dose-escalation or expansion cohorts. In the dose escalation phase, capecitabine doses (2000, 2650, 3500 and 4500 mg/day) were administered at midnight on days 1 to 14 while oxaliplatin and irinotecan were intravenously infused at fixed doses of 50 and 75 mg/m2 respectively on days 1, 8 in a 21-day cycle. The maximum tolerated dose of capecitabine was 2650 mg/day and the most common grade 3 adverse events were neutropenia (30.6%) and diarrhea (13.9%). No grade 4 toxicity was observed. UGT1A1-genotype directed dosing resulted in similar exposure levels of irinotecan, SN-38 and SN-38G in all patients. Objective response rate was 22.2%. Median overall survival and progression-free survival were 8.1 and 5.2 months, respectively. Exploratory immunoprofiling by flow cytometry and quantitative spatial localization analysis of infiltrated immune cells performed on biopsy and plasma samples revealed significant declines in CCL22, CCL2 and TNFα levels at end of first cycle and an active host immune response. Our study showed that OXIRI was well-tolerated and exhibited good efficacy, with immunomodulatory effects. It may be considered as an alternative to FOLFIRINOX in patients intolerant to the latter.

Searching Synergistic Dose Combinations for Anticancer Drugs

Recent development has enabled synergistic drugs in treating a wide range of cancers. Being highly context-dependent, however, identification of successful ones often requires screening of combinational dose on different testing platforms in order to gain the best anticancer effects. To facilitate the development of effective computational models, we reviewed the latest strategy in searching optimal dose combination from three perspectives: (1) mainly experimental-based approach; (2) Computational-guided experimental approach; and (3) mainly computational-based approach. In addition to the introduction of each strategy, critical discussion of their advantages and disadvantages were also included, with a strong focus on the current applications and future improvements.

A minimum core outcome dataset for the reporting of preclinical chemotherapeutic drug studies: Lessons learned from multiple discordant methodologies in the setting of colorectal cancer

In vivo studies in animal models are critical tools necessary to study the fundamental complexity of carcinogenesis. A constant strive to improve animal models in cancer exists, especially those investigating the use of chemotherapeutic effectiveness. In the present systematic review, colorectal cancer (CRC) is used as an example to highlight and critically evaluate the range of reporting strategies used when investigating chemotherapeutic agents in the preclinical setting. A systematic review examining the methodology and reporting of preclinical chemotherapeutic drug studies using CRC murine models was conducted. A total of 45 studies were included in this systematic review. The literature was found to be highly heterogeneous with various cell lines, animal strains, animal ages and chemotherapeutic compounds/regimens tested, proving difficult to compare outcomes between similar studies or indeed gain any significant insight into which chemotherapeutic regimen caused adverse events. From this analysis we propose a minimum core outcome dataset that could be regarded as a standardised way of reporting results from in vivo experimentation.

Cytotoxic effects of the newly-developed chemotherapeutic agents 17-AAG in combination with oxaliplatin and capecitabine in colorectal cancer cell lines

The use of heat shock protein 90 inhibitors like 17-allylamino-17-demethoxy-geldanamycin (17-AAG) has been recently introduced as an attractive anticancer therapy. It has been shown that 17-AAG may potentiate the inhibitory effects of some classical anticolorectal cancer (CRC) agents. In this study, two panels of colorectal carcinoma cell lines were used to evaluate the effects of 17-AAG in combination with capecitabine and oxaliplatin as double and triple combination therapies on the proliferation of CRC cell lines. HT-29 and all HCT-116 cell lines were seeded in culture media in the presence of different doses of the mentioned drugs in single, double, and triple combinations. Water-soluble tetrazolium-1 (WST-1) assay was used to investigate cell proliferation 24 h after treatments. Then, dose-response curves were plotted using WST-1outputs, and IC₅₀ values were determined. For double and triple combinations respectively 0.5 × IC₅₀ and 0.25 × IC₅₀ were used. Data was analyzed with the software CompuSyn. Drug interactions were analyzed using Chou-Talalay method to calculate the combination index (CI).The data revealed that 17-AAG shows a potent synergistic interaction (CI < 1) with oxaliplatin and capecitabine in double combinations (0.5 × IC₅₀) in both cell lines. In the case of triple combinations, the findings showed an antagonistic interaction (CI > 1) in HT-29 and a synergistic effect (CI < 1) in HCT-116 (0.25 × IC₅₀) cell lines. It was concluded that double combinations of 17-AAG with oxaliplatin or capecitabine might be effective against HCT-116 and HT-29 cell lines. However, in triple combinations, positive results were seen only against HCT-116. Further investigation is suggested to confirm the effectiveness of these combinations in clinical trials.

Anticancer potential of Hericium erinaceus extracts against human gastrointestinal cancers

ETHNOPHARMACOLOGICAL RELEVANCE

Hericium is a genus of mushrooms (fungus) in the Hericiaceae family. Hericium erinaceus (HE) has been used for the treatment of digestive diseases for over 2000 years in China. HE possesses many beneficial functions such as anticancer, antiulcer, antiinflammation and antimicrobial effects, immunomodulation and other activities. The aim of the studies was to evaluate the anticancer efficacy of two extracts (HTJ5 and HTJ5A) from the culture broth of HE against three gastrointestinal cancers such as liver, colorectal and gastric cancers in both of in vitro of cancer cell lines and in vivo of tumor xenografts and discover the active compounds.

MATERIALS AND METHODS

Two HE extracts (HTJ5 and HTJ5A) were used for the studies. For the study of chemical constituents, the HTJ5 and HTJ5A were separated using a combination of macroporous resin with silica gel, HW-40 and LH-20 chromatography then purified by semipreparative high-performance liquid chromatography (HPLC) and determined by nuclear magnetic resonance (NMR) spectra. For the in vitro cytotoxicity studies, HepG2 and Huh-7 liver, HT-29 colon, and NCI-87 gastric cancer cell lines were used and MTT assay was performed to determine the in vitro cytotoxicity. For in vivo antitumor efficacy and toxicity studies, tumor xenograft models of SCID mice bearing liver cancer HepG2 and Huh-7, colon cancer HT-29 and gastric cancer NCI-87 subcutaneously were used and the mice were treated with the vehicle control, HTJ5 and HTJ5A orally (500 and 1000 mg/kg/day) and compared to 5-fluorouraci (5-FU) at the maximum tolerated dose (MTD, 25-30 mg/kg/day) intraperitoneally daily for 5 days when the tumors reached about 180-200 mg (mm(3)). Tumor volumes and body weight were measured daily during the first 10 days and 2-3 times a week thereafter to assess the tumor growth inhibition, tumor doubling time, partial and complete tumor response and toxicity.

RESULTS

Twenty-two compounds were obtained from the fractions of HTJ5/HTJ5A including seven cycli dipeptides, five indole, pyrimidines, amino acids and derivative, three flavones, one anthraquinone, and six small aromatic compounds. HTJ5 and HTJ5A exhibited concentration-dependent cytotoxicity in vitro against liver cancer HepG2 and Huh-7, colon cancer HT-29, and gastric cancer NCI-87 cells with the IC50 in 2.50±0.25 and 2.00±0.25, 0.80±0.08 and 1.50±0.28, 1.25±0.06 and 1.25±0.05, and 5.00±0.22 and 4.50±0.14 mg/ml; respectively. For in vivo tumor xenograft studies, HTJ5 and HTJ5A showed significantly antitumor efficacy against all four xenograft models of HepG2, Huh-7, HT-29 and NCI-87 without toxicity to the host. Furthermore, HTJ5 and HTJ5A are more effective than that of 5-FU against the four tumors with less toxicity.

CONCLUSION

HE extracts (HTJ5 and HTJ5A) are active against liver cancer HepG2 and Huh-7, colon cancer HT-29 and gastric cancer NCI-87 cells in vitro and tumor xenografts bearing in SCID mice in vivo. They are more effective and less toxic compared to 5-FU in all four in vivo tumor models. The compounds have the potential for development into anticancer agents for the treatment of gastrointestinal cancer used alone and/or in combination with clinical used chemotherapeutic drugs. However, further studies are required to find out the active chemical constituents and understand the mechanism of action associated with the super in vivo anticancer efficacy. In addition, future studies are needed to confirm our preliminary results of in vivo synergistic antitumor efficacy in animal models of tumor xenografts with the combination of HE extracts and clinical used anticancer drugs such as 5-FU, cisplatin and doxurubicin for the treatment of gastrointestinal cancers.

Phase 2 study of capecitabine and irinotecan combination chemotherapy (modified XELIRI regimen) in patients with advanced gastric cancer

OBJECTIVE

The prognosis of patients with advanced gastric cancer (AGC) remains poor, and no single chemotherapy regimen is recognized as a global standard. A phase 2 trial was conducted to determine the efficacy and tolerability of the modified combination regimen of capecitabine and irinotecan (mXELIRI) in patients with AGC.

METHODS

Patients with earlier untreated AGC received intravenous irinotecan (125 mg/m) over 90 minutes on days 1 and 8, and oral capecitabine (850 mg/m) twice daily on days 2 to 15, every 3 weeks. Treatment was continued for at most 8 cycles or until disease progression or intolerable toxicity.

RESULTS

Thirty-two patients were enrolled. In total, 141 cycles of mXELIRI were administered. The overall response rate was 43.7%, with 1 complete response and 13 partial responses. At a median follow-up of 16.2 months, median time to progression and overall survival were 5.6 months (95% confidence interval, 4.27-6.93 mo) and 11.0 months (95% confidence interval, 8.71-13.29 mo), respectively. The most common hematological adverse event was neutropenia (n=18, 56.3%); grade 3 neutropenia was observed in 5 patients, with neutropenic fever in only 2 patients. The most common grade 3/4 nonhematological toxicities were anorexia (n=3, 9.4%), nausea (n=3, 9.4%), vomiting (n=2, 6.3%), and diarrhea (n=2, 6.3%). There was no treatment-related death.

CONCLUSIONS

mXELIRI is a safe and effective first-line treatment for unresectable and metastatic gastric cancer with a manageable tolerability profile. It can be used as one of the first-line treatment options for patients with AGC.

Irinotecan plus capecitabine as a second-line treatment after failure of 5-fluorouracil and platinum in patients with advanced gastric cancer

OBJECTIVE

This Phase II study was conducted to evaluate the effects of irinotecan plus capecitabine in patients with advanced gastric cancer (AGC) who had received a first-line therapy of 5-fluorouracil/platinum regimen.

METHODS

Patients received capecitabine 1000 mg/m(2) b.i.d. on days 1-14 followed by a 7-day rest period, and irinotecan 100 mg/m(2) was administered through a 90 min intravenous infusion on days 1 and 8, based on a 3-week cycle.

RESULTS

Forty-six (95.8%) of the 48 patients were assessable for response. Thirteen cases of partial response were confirmed, response rate of 27.1% (95% CI, 14.5-39.7%). The median follow-up period was 25.2 months. The median time to progression and overall survival for all patients were 4.1 months (95% CI, 3.4-4.8 months) and 7.6 months (95% CI, 5.1-10.1 months). Grade 3 diarrhea and hand-foot syndrome occurred in eight (17.4%) and two (4.3%) patients, respectively. The most common Grade 3/4 hematological adverse event was neutropenia in four (8.7%) patients. There were no treatment-related deaths during this study.

CONCLUSION

Irinotecan plus capecitabine was a relatively active and tolerable regimen as a second-line chemotherapy for AGC. Further investigation of this regimen is warranted, including the addition of new biological agents such as bevacizumab or cetuximab to improve the salvage regimen.

Predictive and prognostic markers for the outcome of chemotherapy in advanced colorectal cancer, a retrospective analysis of the phase III randomised CAIRO study

We have tested several biomarkers [dihydropyrimidine dehydrogenase (DPD), orotate phosphoribosyl transferase (OPRT), thymidine phosphorylase (TP), thymidylate synthase (TS) and excision cross-complementing gene (ERCC1)] for their prognostic and predictive value in relation to the outcome of chemotherapy in tumour tissues of 556 advanced colorectal cancer (ACC) patients who were randomised between sequential treatment and combination treatment in the CApecitabine, IRinotecan, Oxaliplatin (CAIRO) study. DPD expression showed a statistically significant predictive value for combination treatment with capecitabine plus irinotecan with low versus high values resulting in an improved median progression-free survival (PFS) and median overall survival (OS) of 8.9 (95% confidence interval (CI) 8.3-9.9) versus 7.2 months (95% CI 6.5-8.1, p=0.006), and 21.5 months (95% CI 17.9-26.5) versus 16.9 months (95% CI 13.0-19.1, p=0.04), respectively. In the overall patient population a high OPRT expression in stromal cells was a favourable prognostic parameter for OS, with 21.5 months (95% CI 17.9-27.3) versus 17.2 months (95% CI 15.1-18.6, p=0.036), respectively. A similar effect was observed for PFS. In a multivariate analysis that included known prognostic factors these results remained significant and also showed that a high OPRT expression in tumour cells was an unfavourable prognostic parameter for PFS and OS. In conclusion, in this largest study on capecitabine with or without irinotecan to date we found a predictive value of DPD expression. Our results on the prognostic value of OPRT expression warrant further studies on the role of stromal cells in the outcome of treatments. The divergent results of ours and previous studies underscore the complexity of these biomarkers and currently prevent the routine use of these markers in daily clinical practice.

Phase I clinical and pharmacokinetic study of oxaliplatin, irinotecan and capecitabine

PURPOSE

To determine the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) of the combination of weekly oxaliplatin x 4, weekly irinotecan x 4 and capecitabine Monday through Friday for 4 weeks of every 6 week cycle in patients with solid tumors; to determine the pharmacokinetic profile of these agents in this combination; to observe patients for clinical anti-tumor response.

METHODS

Twenty-two patients with metastatic solid tumors received oxaliplatin 60 mg/m(2) weekly x 4, irinotecan beginning at a dose of 40 mg/m(2) weekly x 4, and capecitabine Monday through Friday for 4 weeks of every 6 week cycle, initially at 1,000 mg twice daily (bid).

RESULTS

The MTD was oxaliplatin 60 mg/m(2) weekly x 4, irinotecan 50 mg/m(2) weekly x 4 and capecitabine 450 mg bid Monday through Friday for 4 weeks of every 6 week cycle. One of six patients at this dose level developed DLT of nausea, vomiting, and diarrhea. Among patients treated with a constant capecitabine dose of 450 mg bid, there was a higher mean AUC of 5-FU in women than in men (mean +/- SD: 892 +/- 287 nM h vs. 537 +/- 182 nM h; Mann-Whitney two-tailed, P = 0.02). There was one complete response in a patient with gastric cancer.

CONCLUSION

The novel schedule of weekly oxaliplatin, weekly irinotecan, and capecitabine Monday through Friday, all administered for 4 weeks of every 6 week cycle, evaluated in this phase I trial is well-tolerated and demonstrated activity in a patient with gastric cancer.

A phase II study of biweekly dose-intensified oral capecitabine plus irinotecan (bXELIRI) for patients with advanced or metastatic gastric cancer

Capecitabine, a prodrug of 5-FU, has been reported to generate maximal tumour activity at tumour sites and/or to improve drug tolerability as compared with 5-FU infusion, and it has also been demonstrated to act synergistically with irinotecan against some solid cancers. A previous study concluded that dose-intensified biweekly capecitabine seems to be more effective at increasing both response rate and progression-free survival time than conventional dose and schedule of capecitabine in colon cancer. We conducted this study to ascertain the efficacy and toxicity of dose-intensified biweekly capecitabine and irinotecan combination chemotherapy in chemotherapy-naïve advanced or metastatic gastric cancer patients. Patients were treated with irinotecan 130 mg m(-2) intravenously for 90 min on days 1 and 15. Capecitabine at 3500 mg m(-2) day(-1), divided into two sessions per day, was administered for seven consecutive days from days 1 and 15, and followed by a 7-day drug-free period, respectively. Fifty-five eligible patients were enrolled in this study from November 2003 to April 2006. There were 22 women and 33 men: median patient age was 54 years (range: 27-81). A total of 200 treatment cycles were administered at a median number of four per patient (range: 1-9). Intent-to-treatment analysis showed that one patient achieved complete response (1.8%), 23 partial response (41.8%), 15 stable disease (27.3%), 10 progressive disease (18.2%) and 6 were non-evaluable (10.9%). The overall response rate was 43.6% (95% confidence interval: 30.2-56.9). The common grade 3-4 toxicities were neutropenia in 12 (21.8%), nausea/vomiting in 3 (5.4%) and diarrhea in 4 (7.2%) patients. Median time to progression was 5 months (range: 0.5-11 months), median survival duration was 11 months (range: 0.5-45 months) and median response duration was 6 months (range: 0.5-9 months). Biweekly dose-intensified capecitabine and irinotecan combination chemotherapy was active for the treatment of advanced or metastatic gastric cancers with a tolerable safety profile.

A phase I study of capecitabine and a modulatory dose of irinotecan in metastatic breast cancer

PURPOSE

There is a need for chemotherapy regimens active against anthracycline- and taxane-refractory breast cancer. Data from preclinical and pilot studies performed at Roswell Park Cancer Institute (RPCI) suggested that when irinotecan (IRN) is given with 5-fluorouracil (5-FU) efficacy is affected by the sequence of drug administration. Pretreatment with IRN 24 h before 5-FU increased the number of tumor cells in S-phase and the antitumor activity in a preclinical system. These data provided the rationale for the evaluation of IRN and capecitabine, a 5-FU prodrug, sequentially administered in patients with metastatic breast cancer. The main objective of the study was to determine the MTD and identify dose-limiting toxicities (DLTs) of capecitabine and IRN. Additionally, the degree of accumulation of cells in S-phase in tumor biopsies obtained at 24 h after the first dose of IRN was measured in consenting patients.

PATIENTS AND METHODS

Metastatic breast cancer patients who experienced disease progression after at least one (taxane or anthracycline based) chemotherapy regimen and an expected survival of at least 3 months and ECOG performance status 0-2 were eligible. Twelve patients were enrolled and treated. The starting doses were IRN 80 mg/m(2) given over 90 min on days 1, 8, 22, 29, and capecitabine 1,500 mg/m(2)/day given days 2-15 and 23-36. Evaluation for response was performed after the first cycle. Sequential tumor biopsies were performed on five patients.

RESULTS

The first three patients treated exhibited modulation in cyclin A index on tumor biopsy as defined by the study, defining the modulatory dose of IRN as 80 mg/m(2). Overall, 4/5 biopsies showed modulation. Dose Limiting Toxicities (DLTs) were assessed during the first cycle of therapy. Two DLTs (Grade 3 nausea vomiting and dehydration; grade 3 pneumonia, hypoxia, hypotension) were seen at dose level 2 of capecitabine (2,000 mg/m(2)/day) and the first cohort was expanded. There were no DLTs for patients treated at DL 1. No grade 3-4 toxicities occurred at DL 1. Seven patients were evaluable for response following one cycle of treatment (partial response 1, stable disease 4, progressive disease 2) Of the five inevaluable patients, two experienced DLT, one received 50% of the planned capecitabine dose, one progressed prior to evaluation, and one withdrew consent.

CONCLUSION

IRN 80 mg/m(2) days 1, 8, 22, 29 in combination with capecitabine 1,500 mg/m(2)/day in divided dose days 2-15 and 23-36 has an acceptable toxicity profile and resulted in modulation of S-phase in 4/5 specimens examined. Further studies of the activity of this combination and modulatory effect of IRN are warranted.

Pharmacokinetic and safety study of weekly irinotecan and oral capecitabine in patients with advanced solid cancers

BACKGROUND

Capecitabine and irinotecan have demonstrated in vitro synergistic anti-cancer activity, and both are substrates for carboxyl esterases (CES). We conducted a study to identify a safe dose and potential drug-drug interactions of this combination.

METHODS

This was an open-label phase I dose escalation trial. Irinotecan was given as a 30 min infusion on days 1 and 8, and capecitabine on days 1-14 of a 21-day cycle. Plasma for pharmacokinetic analyses was drawn on days 1 and 8.

RESULTS

Forty-seven patients with advanced solid tumors received 202 cycles of chemotherapy in 6 dose cohorts. At the highest dose tested, 1 of 3 patients developed fatal neutropenia and gram-negative sepsis. At dose level 5 (100/2000), 2 of 28 patients developed cycle 1 DLT-grade 3 diarrhea/vomiting, and grade 3 diarrhea. Responses were observed in 9 of 35 (5 of 9 ovarian cancer) evaluable patients. The AUC((0-last)) of irinotecan, SN-38G, and APC were similar on days 1 and 8. However, SN-38 T(max) was longer on Day 8 (0.88 h vs. 1.23 h, p = 0.012). While SN-38 AUC((0-last)) was lower on day 8 by 35%, this was not statistically significant (p = 0.123).

CONCLUSIONS

Capecitabine results in a significantly delayed conversion of irinotecan to SN-38, suggesting drug-drug interaction at the level of CES. This suggests caution should be used when irinotecan is combined with substrates of CES, and warrants further study. The combination of irinotecan and capecitabine is safe and well tolerated at 100/2000, and warrants further evaluation in ovarian and breast cancer.

Irinotecan, oxaliplatin and raltitrexed for the treatment of advanced colorectal cancer

Out of every 17-18 individuals in the US, one develops colorectal cancer (CRC) in their lifetime. Of individuals diagnosed with CRC, > 50% present or develop metastatic disease, which, if untreated, is associated with 6-9 months median survival. Although surgical resection is the primary treatment modality for CRC, chemotherapy is the mainstay of treatment for metastatic or unresectable disease. For nearly three decades, 5-fluorouracil (5-FU) has been the chemotherapy of choice for treatment of CRC. However, the response rates to single 5-FU therapy have been suboptimal with an objective tumour response of 10-20%. Attempts have been made to improve the efficacy of 5-FU by either schedule alteration (protracted infusion versus intravenous push) or biochemical modulation with leucovorin (LV). Continuous infusion induced more tumour regression and prolonged the time-to-disease progression with some significant impact on survival (11.3 versus 12.1 months; p < 0.04). 5-FU/LV resulted in a significant increase in overall response rates and in the prolongation of disease-free survival in the adjuvant setting, although severe toxicities represent a major clinical problem. The last 10 years have seen the addition of several new agents such as irinotecan, oxaliplatin, raltitrexed, bevacizumab and cetuximab. The prognosis has significantly improved with the addition of these agents, with median survivals now > 20 months. This review paper focuses on irinotecan, oxaliplatin and raltitrexed when used alone and in combination.