Bevacizumab in combination with oxaliplatin, fluorouracil, and leucovorin (FOLFOX4) for previously treated metastatic colorectal cancer: results from the Eastern Cooperative Oncology Group Study E3200

Panitumumab monotherapy in patients with previously treated metastatic colorectal cancer

BACKGROUND

The safety and efficacy of the fully human antibody panitumumab was evaluated in patients with metastatic colorectal cancer refractory to available therapies.

METHODS

This phase 2 open-label, multicenter study of panitumumab enrolled patients with metastatic colorectal cancer who had progressed on chemotherapy that included a fluoropyrimidine and irinotecan or oxaliplatin, or both. All patients had tumors with > or =10% 1+ epidermal growth factor receptor (EGFr) staining by immunohistochemistry. Patients were stratified into 2 strata (high or low staining intensity) and received intravenous panitumumab 2.5 mg/kg weekly 8 of every 9 weeks until disease progression or unacceptable toxicity.

RESULTS

In all, 148 patients received panitumumab, 105 in the high EGFr stratum, 43 in the low EGFr stratum. Overall response by central review was 9% (95% confidence interval [CI], 5%-15%) and was similar between strata. An additional 29% of patients had stable disease. Median progression-free survival was 14 weeks (95% CI, 8-16) and median overall survival was 9 months (95% CI, 6-10). Toxicities were manageable, with skin toxicity reported in 95% of patients (5% grade 3 or 4). Four patients discontinued therapy because of toxicity. No antipanitumumab antibodies were detected. One patient had an infusion reaction but was able to continue therapy.

CONCLUSIONS

Panitumumab given weekly was well tolerated and had single-agent activity in previously treated patients with colorectal cancer. Dermatologic toxicity was common but rarely severe. Ongoing studies will determine panitumumab activity earlier in the course of treatment for colorectal cancer and in combination with other antineoplastic agents.

Spectrum of activity and mechanism of action of VEGF/PDGF inhibitors

BACKGROUND

Angiogenesis plays an important role in tumor growth and metastasis.

METHODS

We review the function of the vascular endothelial growth factor (VEGF) in vessel formation that is complemented by platelet-derived growth factor (PDGF). We also review the agents designed to target VEGF, PDGF, and/or their receptors.

RESULTS

VEGF plays a central role in tumor angiogenesis. It is expressed at increased levels in colorectal, liver, lung, thyroid, breast, as well as in bladder, ovary, uterine cancers, and in angiosarcomas, germ cell tumors, intracranial tumors, and others. VEGF blockade has been shown to have a direct and rapid antivascular effect in both animal and human tumors, through deprivation of tumor vascular supply and inhibition of endothelial proliferation. Overexpression of PDGFs and their receptors has also been reported in many types of cancers such as prostate, ovarian, and non-small-cell lung cancer. Many VEGF and PDGF inhibitors are available. The use of some of these inhibitors has significantly improved the survival of cancer patients. Several agents are in development and currently are being tested in clinical trials.

CONCLUSIONS

Angiogenic agents inhibiting VEGF and PDGF have shown promising clinical results. Targeting more than one pathway by combining different agents may increase the antitumor activity of these drugs. The implementation of reliable radiologic and pathologic angiogenesis monitoring techniques is necessary to implement antiangiogenic therapies in cancer.

Survival and disease-progression benefits with treatment regimens for advanced colorectal cancer: a meta-analysis

BACKGROUND

Many randomised trials have compared different systemic treatment regimens in patients with advanced colorectal cancer. While survival advances have apparently been achieved, the magnitude of these incremental benefits across diverse regimens is less clear. The aim of our study was to estimate the magnitude of survival and disease progression benefits with the use of different regimens in patients with advanced colorectal cancer.

METHODS

We systematically reviewed randomised trials comparing systemic treatment regimens in advanced colorectal cancer. Treatment was categorised by use of or no use of fluorouracil-based regimens, irinotecan, oxaliplatin, bevacizumab, and cetuximab. We used multiple-treatment meta-analysis methodology to combine information from direct comparisons (ie, treatments compared within a randomised trial) and indirect comparisons (ie, treatments compared between trials by combining results on how effective they are against a common comparator treatment) of different chemotherapy regimens. The primary endpoint was death and the secondary endpoint was disease progression. Monte Carlo simulations were used to establish which regimen offered the most benefit for these endpoints. We did analyses of all trials and analysed separately trials that studied first-line treatments and non-first-line treatments.

FINDINGS

242 trials published in 1967-2007 (N=56 677 patients) involved 137 different chemotherapy regimens. 37 of these trials were eligible for the multiple-treatment meta-analysis, according to our categorisation, including 47 comparisons of data on death (N=13 875 patients) and 48 comparisons of data on disease progression (N=15 158 patients). Compared with fluorouracil plus leucovorin alone, the risk of death was most decreased with the addition of irinotecan plus bevacizumab (hazard ratio [HR] 0.60, 95% credibility intervals (CrI) 0.44-0.84) and considerable benefits were also noted with addition of irinotecan plus oxaliplatin (HR 0.72 [95% CrI 0.54-0.97]); oxaliplatin plus bevacizumab (HR 0.72 [0.57-0.90]); bevacizumab alone (HR 0.78 [0.60-1.03]); and oxaliplatin alone (HR 0.87 [0.78-0.98]). The disease progression benefits were even more prominent for the addition of irinotecan plus bevacizumab (HR 0.41 [0.28-0.60]); irinotecan plus oxaliplatin (0.53 [0.38-0.73]); oxaliplatin plus bevacizumab (0.46 [0.34-0.61]); bevacizumab alone (0.56 [0.41-0.76]); oxaliplatin alone (0.64 [0.56-0.73]); irinotecan plus cetuximab (HR 0.62 [0.42-0.92]); and irinotecan alone (HR 0.73 [0.65-0.82]). Findings were similar for first-line and non-first-line treatment analyses although data were sparse for non-first-line treatment analyses. Compared with a patient with an anticipated 1-year survival who is treated with fluorouracil and leucovorin, the absolute survival benefit is estimated at 8 months' prolongation with addition of irinotecan plus bevacizumab, 4.7 months' prolongation with addition of oxaliplatin plus bevacizumab or irinotecan plus oxaliplatin, and 1-1.8 months' prolongation with addition of irinotecan alone or oxaliplatin alone.

INTERPRETATION

Distinct incremental benefits are noted for diverse chemotherapy regimens in patients with advanced colorectal cancer, with more prominent effects on disease progression than on death. More data are needed at least for the newest drugs to estimate more accurately the magnitude of the benefit derived from their use.

Effective second-line treatment with cetuximab and bevacizumab in a patient with hepatic metastases of colorectal cancer and hyperbilirubinemia

BACKGROUND

Irinotecan-based second-line chemotherapy of metastatic colorectal cancer (CRC) is effective, it might, however, be contraindicated in cases of severe liver dysfunction due to advanced liver metastases.

CASE REPORT

A 57-year-old woman with diffuse CRC liver metastases showed progressive disease on first-line treatment with capecitabine and oxaliplatin (XELOX). Chronic cholestasis and hyperbilirubinemia caused by advanced liver involvement prohibited second-line treatment with irinotecan-based chemotherapy. We initiated combined antibody treatment with cetuximab and bevacizumab.

RESULTS

Clinical performance status as well as laboratory parameters improved rapidly. Staging investigations after 8 weeks revealed a partial remission. Since bilirubin levels had returned to the upper limit of normal, therapy could be changed to standard irinotecan, 5-fluorouracil, folinic acid, and bevacizumab.

CONCLUSION

Combined treatment with cetuximab and bevacizumab may be considered as an effective treatment option in patients who cannot be treated with standard chemotherapy regimens due to impaired liver metabolism of cytotoxic substances.

Molecular-targeted therapies: lessons from years of clinical development

Over the past decade, molecular-targeted therapies have been added to cytotoxic and anti-endocrine drugs in the treatment of cancer, with the aim to target the molecular pathways that underlie the carcinogenic process and maintain the cancer phenotype. Success with some of these agents has suggested that identification and validation of the drug target is the starting point for the route of development of active, safe and effective drugs. Main molecular targets used to the development of anticancer drugs are cell surface receptors, signal transduction pathways, gene transcription targets, ubiquitin-proteasome/heat shock proteins and tumour microenvironment components (especially antiangiogenic agents). Here, we review the development of the main molecular targeted non-cytotoxic agents studied in cancer, highlighting lessons derived from the development of these novel drugs and proposing new horizons for the clinical development of molecular-targeted therapies.

Third-line therapy for metastatic colorectal cancer

BACKGROUND

The past years' therapy for colorectal cancer has evolved rapidly with the introduction of novel cytotoxic agents such as irinotecan, capecitabine and oxaliplatin. Further advances have been achieved with the integration of targeted agents such as bevacizumab, cetuximab and recently, panitumumab. As a result, third-line treatment is now a necessary step in the optimal treatment of patients with metastatic colorectal cancer (MCRC).

MATERIALS AND METHODS

We conducted a literature review of English language publications on third-line therapy for MCRC from January 2000 to April 2007. Data on median overall survival (mOS), median time to progression (mTTP) and response rate were recorded.

RESULTS

We found 27 articles and 22 abstracts to fulfil the criteria. Patients who received regimens containing oxaliplatin and infusional 5-fluorouracil (5-FU) demonstrated mTTP up to 7 months and a mOS of 16 months. With irinotecan and 5-FU, mOS around 8 months were reported and with cetuximab combined with irinotecan, the highest mOS was 9.8 months.

CONCLUSION

Third-line therapy in advanced colorectal cancer may improve mOS for patients with MCRC. Therefore, randomized studies should be conducted in the future.

Antiangiogenic therapy for ovarian cancer

PURPOSE OF REVIEW

To highlight the current antiangiogenic compounds being evaluated as single agents or in association with chemotherapy in the treatment of ovarian cancer, as well as the rationale for their development.

RECENT FINDINGS

Several proangiogenic factors may be potential targets for antiangiogenic therapy in ovarian cancer. Bevacizumab, a monoclonal antibody against vascular endothelial growth factor, has been evaluated as a single agent in two phase II clinical trials and in combination with chemotherapy in three phase II studies, with promising results. This agent is also being evaluated in association with chemotherapy in two phase III clinical trials, both in the treatment and in the maintenance settings. Heparanase inhibitors and inhibitors of platelet-derived growth factor signalling remain as potential agents to be investigated in phase II trials. The development of biomarkers to define appropriate dosing regimens and predict which patients may benefit from antiangiogenic therapies is of great importance.

SUMMARY

Data from preclinical and clinical studies reported in the last 2 years demonstrate the importance of several proangiogenic factors in the prognosis of ovarian cancer, suggesting possible new targets for antiangiogenic therapy. The agents that are currently being investigated in phase II and III clinical trials include bevacizumab, erlotinib, sunitinib, sorafenib and vascular endothelial growth factor Trap, and the results of these trials will have significant implications in the future management of ovarian cancer.

Bevacizumab 5 mg/kg Can Be Infused Safely Over 10 Minutes

Purpose

Bevacizumab is a humanized monoclonal antibody that targets vascular endothelial growth factor. As a result of concerns for potential infusion-related hypersensitivity reactions (HSRs), initial phase I trials used a 90-, 60-, 30-minute initial infusion sequence. We sought to determine if the initial prolonged infusion was still necessary and if an infusion time of fewer than 30 minutes could be safely used.

Methods

We used computerized pharmacy records to identify all patients who received bevacizumab at our institution in the first 2 years of commercial availability (February 1, 2004, to June 30, 2006). Our institutional adverse drug reaction reporting program was used to identify any infusion reactions possibly related to bevacizumab, and patient medical records were reviewed for confirmation.

Results

A total of 1,077 patients were treated with 10,606 doses of bevacizumab, and 765 of these patients received a 5-mg/kg dose (total of 8,494 doses). No HSRs occurred with the 90-, 60-, 30-minute infusion sequence in the first 202 patients. The standard infusion rate was then modified to 30 minutes for all bevacizumab doses. No HSRs were encountered. The infusion was again modified to a rate of 0.5 mg/kg/min. Of the 370 patients who received a total of 2,311 doses of bevacizumab at 5 mg/kg over 10 minutes, six (1.6%) experienced events of minor clinical consequence that were possibly consistent with nonserious HSRs.

Conclusion

Ninety- and 60-minute initial infusion times are unnecessary. Use of a standard infusion rate of 0.5 mg/kg/min is safe, logical, and the current policy at our institution.

Front-line bevacizumab in combination with oxaliplatin, leucovorin and 5-fluorouracil (FOLFOX) in patients with metastatic colorectal cancer: a multicenter phase II study

Purpose

To evaluate the efficacy and the toxicity of front line FOLFOX4 combined with bevacizumab in patients with metastatsic CRC (mCRC).

Patients and Methods

Chemotherapy-naïve patients with mCRC, received bevacizumab (5 mg/kg every 2 weeks d₁), oxaliplatin (85 mg/m² on d₁), leucovorin (200 mg/m²) on days 1 and 2 and 5-Fluorouracil (400 mg/m² as i.v. bolus and 600 mg/m² as 22 h i.v. continuous infusion on days 1 and 2) every 2 weeks.

Results

Fifty three patients (46 with a PS 0–1) were enrolled. Complete and partial response was achieved in eight (15.1%) and 28 (52.8%) patients, respectively (ORR: 67.9%; 95% C.I.: 53.8%–92%); 11 (20.7%) patients had stable disease and six (11.3%) progressive disease. With a median follow up period of 13.5 months, time to tumor progression was 11 months while the median survival has not yet been reached; the probability of 1-, 2- and 3- year survival was 79.8%, 63.8% and 58.3%, respectively; Two patients relapsed during the follow up period. Eight (15%) patients underwent metastasectomy with R0 resections. Grade 3–4 neutropenia occurred in 15.1% of patients and one (1.9%) of them presented febrile neutropenia. Non-hematologic toxicity included grade 3 diarrhea (7.6%) and grade 2 and 3 neurotoxicity in 16.9 and 15.1% of patients, respectively. One (1.9%) patient presented pulmonary embolism and one (1.9%) cardiac ischaemia. There was one (1.9%) sudden death after the first cycle.

Conclusion

The combination of FOLFOX4/bevacizumab appears to be highly effective, well tolerated and merits further evaluation in patients with mCRC.

Bevacizumab in the treatment of colorectal cancer

Colorectal cancer is a common disease with therapy that has a proven effectiveness in the adjuvant and metastatic setting. Bevacizumab, a vascular endothelial growth factor inhibitor, is an antiangiogenesis monoclonal antibody that has benefit in response rate and overall survival when used in combination with existing metastatic colorectal cancer regimens. It is well tolerated with a few important side effects to be cognizant of, including hypertension, arterial thrombosis and bowel perforation. Existing treatment and research strategies are examining its use in the adjuvant setting or in combination with other angiogenesis inhibitors.

Efficacy and safety of bevacizumab in combination with oxaliplatin, irinotecan and fluoropyrimidine-based therapy in advanced colorectal cancer

Background: Bevacizumab is an anti-VEGF, humanized mAb that is the most advanced agent of its class in clinical development. Several studies have examined bevacizumab in combination with chemotherapy in the first- and second-line settings in patients with metastatic CRC. Despite of that, there is lack of information concerning the extent to which bevacizumab can be used to treat metastatic CRC. We still need more evidence related to efficacy and safety of bevacizumab in different settings, or sequential treatments. The aim of this study was to investigate efficacy and safety of bevacizumab added to different chemotherapy in patients with metastatic CRC. Methods: This was a controlled, prospective, multicentre, cohort study. Thirty patients with advanced colorectal cancer were enrolled into this study. Bevacizumab was applied with oxaliplatin-, irinotecan-, 5FU- or capecitabine -based chemotherapy in the first-, second- or third-therapy lines. Totally 261 cycles were applied. The median number of applied cycles per patient was 8 (range 2-16). Results: Objective tumor response (RR) was seen in 11 patients 37% (95%CI 19-69%) calculated on an intention-to-treat basis. The median duration of response was 12 months. Three of 11 patients (27%) with PR had secondary surgery. RR was seen in 9 of 16 patients (56%) who received bevacizumab in the first-line treatment and in 2 of 14 patients (14%) who received therapy in the second+ lines (p=0.02). Clinical benefit (PR+SD) was seen in 22 (74%) patients. 75% of patients achieved clinical benefit in the first-line and 74% in the second+ chemotherapy lines. The median time to progression (TTP) of the patients is was 9 + months (95%CI 7 - + ?) at the moment of this analysis. The median TTP of patients who received bevacizumab in the first line was 11 months (95%CI 8 - + ?). The median TTP of patients who received bevacizumab in the second+ lines was 5.5 months (95%CI 4 - + ?) (p=0.015). The median survival time (OS) for all patients was 9 + months (95%CI 7 - + ?). The median OS at the moment of analysis was 11 months (95%CI 9 - + ?) for patients receiving bevacizumab in the first line, and 7 months for patients receiving the drug in the second+ lines (95%CI 6 - + ?) (p=0.024). The incidence of any toxicity grade 3-4 was less than 10%. Bevacizumab associated incidence of grade 3-4 side effects did not exceed 5%. Hypertension 5% and thromboembolism 5% were the most frequent events. Gastrointestinal perforation did not occur. There was one toxic death due to sepsis and not directly associated with bevacizumab toxicity. Conclusion: Bevacizumab can safely be added to different chemotherapeutic regimens in first- and second+ line. The conferred benefit in overall survival, TTP and response rate obviously requires randomized trials.