Bevacizumab in association with de Gramont 5-fluorouracil/folinic acid in patients with oxaliplatin-, irinotecan-, and cetuximab-refractory colorectal cancer: a single-center phase 2 trial

A phase I/II study of nintedanib and capecitabine for refractory metastatic colorectal cancer

BACKGROUND

Nintedanib is a tyrosine kinase inhibitor with efficacy in bevacizumab-resistant colorectal cancer models. This phase I/II study evaluated the recommended phase II dose and efficacy of nintedanib and capecitabine in refractory metastatic colorectal cancer.

METHODS

Key eligibility criteria included refractory metastatic colorectal cancer and ECOG performance status of 1 or lower. The primary endpoint was 18-week progression-free survival (PFS). A 1-sided binomial test (at α = .1) compared the observed 18-week PFS with a historic control of .25.

RESULTS

Forty-two patients were enrolled, including 39 at the recommended phase II dose. The recommended phase II dose was established to be nintedanib 200 mg by mouth twice daily and capecitabine 1000 mg/m2 by mouth twice daily. The protocol was evaluated for efficacy in 36 patients. The 18-week PFS was 42% (15/36 patients; P = .0209). Median PFS was 3.4 mo. Median overall survival was 8.9 mo. Sixteen (44%) patients experienced a grade 3/4 adverse event, most commonly fatigue (8%), palmoplantar erythrodysesthesia (8%), aspartate aminotransferase elevation (6%), asthenia (6%), pulmonary embolus (6%), and dehydration (6%). Osteopontin levels at cycle 1, day 1 and cycle 3, day 1 as well as ΔCCL2 levels correlated to disease control at 18 weeks.

CONCLUSIONS

The combination of nintedanib and capecitabine is well tolerated. Clinical efficacy appears to be superior to regorafenib or tipiracil hydrochloride monotherapy. Further investigation of similar combinations is warranted.

CLINICALTRIALS.GOV IDENTIFIER

NCT02393755.

A systematic review of salvage therapies in refractory metastatic colorectal cancer

PURPOSE

Established that the only approved agents in previously treated metastatic colorectal cancer (CRC) are trifluoridine/tipiracil and regorafenib, we conducted a systematic review of all the published phase 2-3 trials, with the scope to evaluate the benefit of any later-line regimens in refractory metastatic CRC.

METHODS

Phase 2-3 studies that enrolled patients with stage IV disease receiving salvage therapies for refractory CRC were identified using electronic databases (Pubmed, EMBASE, and Cochrane Library). Clinical outcomes were pooled using a point estimates for the weighted values of median overall survival (OS), progression-free survival (PFS), response rate (ORR), stable disease rate (SD), and 6-month and 1-year OS.

RESULTS

Overall, 7556 patients were included from 67 studies (n = 70 arms). Overall, the pooled ORR and SD were 15.4% (95% CI 13-18%) and 36.9% (95% CI 33.5-40.6%). Median PFS, 6-month and 1-year OS, and median OS were 3.2 (95% CI 2.9-3.3) months, 65.4% (95% CI 61.9-68.8%), 36% (95% CI 32.3-39.9%) and 8.8 (95% CI 8.3-9.2) months. Overall survival was different in the monochemotherapy, polychemotherapy, chemotherapy + targeted therapy, and targeted therapy alone arms (7.6, 9.5, 10.3, and 7.9 months, respectively, P for difference = 0.01). Median PFS were respectively 2.3, 3.9, 3.8, and 2.6, respectively (P for difference < 0.01).

CONCLUSIONS

Overall, combination therapy (polychemotherapy with or without targeted agents) is associated with a higher control of disease and better outcome than approved agents. Treatment, if possible, should be personalized according to the patients' conditions, physician preference and molecular profile of disease.

Comparative Effectiveness and Safety of Monoclonal Antibodies (Bevacizumab, Cetuximab, and Panitumumab) in Combination with Chemotherapy for Metastatic Colorectal Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

The last decade has seen the increasing use of biological medicines in combination with chemotherapy containing 5-fluorouracil/oxaliplatin or irinotecan for the treatment of metastatic colorectal cancer (mCRC). These combinations have resulted in increased progression-free survival (PFS) in patients with mCRC; however, there are remaining concerns over the extent of their effect on overall survival (OS). Published studies to date suggest no major differences between the three currently available monoclonal antibodies (MoAbs); however, there are differences in costs. In addition, there is rising litigation in Brazil in order to access these medicines as they are currently not reimbursed.

OBJECTIVE

The aim was to investigate the comparative effectiveness and safety of three MoAbs (bevacizumab, cetuximab and panitumumab) associated with fluoropyrimidine-based chemotherapy regimens and compared to fluoropyrimidine-based chemotherapy alone in patients with mCRC, through an updated systematic review and meta-analysis of concurrent or non-concurrent observational cohort studies, to guide authorities and the judiciary.

METHOD

A systematic review and meta-analysis was performed based on cohort studies published in databases up to November 2017. Effectiveness measures included OS, PFS, post-progression survival (PPS), Response Evaluation Criteria In Solid Tumors (RECIST), response rate, metastasectomy and safety. The methodological quality of the studies was also evaluated.

RESULTS

A total of 21 observational cohort studies were included. There were statistically significant and clinically relevant benefits in patients treated with bevacizumab versus no bevacizumab mainly around OS, PFS, PPS and the metastasectomy rate, but not for the disease control rates. However, there was an increase in treatment-related toxicities and concerns with the heterogeneity of the studies.

CONCLUSION

The results pointed to an advantage in favor of bevacizumab for OS, PFS, PPS, and metastasectomy. Although this advantage may be considered clinically modest, bevacizumab represents a hope for increased survival and a chance of metastasectomy for patients with mCRC. However, there are serious adverse events associated with its use, especially severe hypertension and gastrointestinal perforation, that need to be considered.

Bevacizumab plus chemotherapy as third- or later-line therapy in patients with heavily treated metastatic colorectal cancer

Background

Currently available third- or later-line therapy for metastatic colorectal cancer (mCRC) is limited in its efficacy, with a weak survival benefit in patients who progressed after two or more lines of standard therapy. Our retrospective study aimed to explore the value of bevacizumab plus chemotherapy in this setting.

Methods

Patients with mCRC who received fluoropyrimidine, oxaliplatin, and irinotecan as first- and second-line chemotherapy were selected for inclusion. Treatment consisted of bevacizumab plus chemotherapy. Chemotherapy consisted mainly of oxaliplatin, irinotecan, and fluoropyrimidine.

Results

Between February 2010 and December 2012, 35 consecutive patients with mCRC were treated with bevacizumab plus chemotherapy as a third- or later-line treatment. No complete responses, seven partial responses (20%), 22 stable disease responses (62.9%), and six progressive disease responses (17.1%) were obtained, producing an objective response rate of 20% and a disease control rate of 82.9%. With a median follow-up of 11.3 months (range: 0.7–48.0 months), the median progression-free survival was 5.98 months (95% confidence interval: 4.76–7.2 months), and the median overall survival was 14.77 months (95% confidence interval: 11.45–18.1 months). In the univariate analysis, patients with a primary colon tumor might have had a longer overall survival than patients with a primary rectal tumor (18.8 months vs 11.1 months, respectively; P=0.037). Common chemotherapy-related toxicities were nausea/vomiting (48.6%), fatigue (34.3%), leucopenia (40%), neutropenia, (42.9%), and anemia (42.9%), with one patient with grade 3 neutropenia, and two patients with grade 3 thrombocytopenia. The common bevacizumab-associated toxicity was hypertension (31.4%). None of the patients discontinued therapy or died because of bevacizumab-associated toxicities.

Conclusion

Our data showed that adding bevacizumab to third- or later-line therapy might lead to tumor control and improved survival in heavily pretreated mCRC patients. In addition, preliminary data suggested that primary colon cancer was more likely to benefit from bevacizumab-containing regimens. Toxicities were acceptable, and no new toxicity was identified. Further studies are needed to validate these findings.

Uracil/tegafur as a possible salvage therapy in chemo-refractory colorectal cancer patients: a single institutional retrospective study

AIM OF THE STUDY

Our aim was to determine the activity and toxicity of uracil/tegafur and leucovorin combination in metastatic colorectal cancer (mCRC) patients who have progressed with all currently active agents.

MATERIAL AND METHODS

This study was a retrospective analysis of 50 mCRC patients who had previously failed to respond to all available chemotherapeutics and who received subsequent treatment with uracil/tegafur 250 mg/m(2) d1-5 in combination with leucovorin 90 mg/day, d1-5 followed by two days' rest.

RESULTS

The median age of the patients was 60 years. Most of them (60%) were male. Bevacizumab was used in 65% and cetuximab in 55% of the patients. Thirty-nine patients (78%) were treated with uracil/tegafur in the fourth line setting. The median treatment duration was 4.2 months (range, 2-24 months). The objective response rate and the disease control rate were 4% and 34%, respectively. Median progression-free survival was 4.1 months (95% CI, 3.6-4.6 months) and overall survival was 6.6 months (95% CI, 4.5-8.6 months). Grade 3 or 4 toxicity was seen in 20% (n = 10) of the patients while 60% (n = 6) of them required dose reductions.

CONCLUSIONS

This retrospective data show that uracil/tegafur may be considered in heavily pretreated mCRC patients because of its activity, lower toxicity, and feasibility.

[Anti-angiogenic treatments in metastatic colorectal cancer: Does a continuous angiogenic blockade make sense?]

Ten years after the approval of bevacizumab in colorectal cancer patients, results from ML18147 and CORRECT studies have recently demonstrated the possibility to target angiogenesis in patients previously exposed to anti-VEGF. An increasing number of anti-angiogenic treatments are now available, however, no biomarker has yet succeeded in rationalizing our therapeutic strategies. Nevertheless, several lessons have been learned from preclinical and pivotal clinical studies. The first clinical trials demonstrated a survival benefit, adding VEGFA targeting monoclonal antibodies to chemotherapy in metastatic colorectal cancer patients (AVF2107, ECOG 3200). Many phase III clinical trials confirmed the interest of this strategy, in combination with chemotherapies containing irinotecan, oxaliplatin, or with 5-fluorouracil in monotherapy. To date, such results have not been reproduced with tyrosine kinase inhibitors targeting the angiogenesis pathways, with an increasing rate of chemotherapy related toxicities. Clinical trials performed in the adjuvant setting (AVANT, NSABPC08) failed to demonstrate any efficacy of the anti-VEGFA treatments on the micrometastatic disease, encouraging its prescription in the unresectable cases. On the other hand, a continuous inhibition of angiogenesis during the course of the metastatic disease was shown to be feasible and to extend colon cancer patient's survival in two recent randomized trials. For these patients, the continuation of bevacizumab beyond progression in first line improves overall survival. Lastly, results achieved by the CORRECT and CONCUR studies demonstrated that anti-angiogenics might be effective in colorectal cancers resistant to chemotherapy. This review presents the main results of preclinical and clinical studies sustaining the prescription of anti-angiogenics in metastatic colorectal cancers. The future challenge is to promote the development of biomarkers to enable the stratification of the different therapeutic strategies.

Incorporating anti-VEGF pathway therapy as a continuum of care in metastatic colorectal cancer

Metastatic cancer was previously treated with distinctive lines of chemotherapy regimens upon disease progression or toxicity, yet the choices of therapy are actually interrelated, with the selection of a first-line regimen in part determining the choices available for subsequent treatment. Lately the therapeutic approach based on separate lines of treatment, tends to be replaced from a perspective strategical approach, that of the "continuum of care". This strategy targets to an improved overall survival, improved of quality of life and minimization of toxicity through upfront design of treatment selection and sequencing, exposure to all available drugs and minimization of unnecessary treatment. Anti-VEGF treatment has a well-documented role in this approach. Bevacizumab should be included in upfront treatment regimens for all mCRC patients independently of RAS status, unless contraindicated. Upfront bevacizumab could be combined with all available regimens since the optimal choice of backbone chemotherapy is yet to be defined. In RAS wild-type population, when metastasectomy is the target, an anti-EGFR combination is also a valid approach. Maintenance with bevacizumab and fluoropyrimidines should be considered upon intolerance of induction treatment and/or disease stabilization; maintenance with bevacizumab monotherapy should be avoided. In highly selected patients, complete treatment cessation could be also an option. Continuation with bevacizumab upon first progression and switch of the "backbone" chemotherapy is a validated approach. Patients progressing after first-line oxaliplatin regimen including bevacizumab combinations could be treated with an aflibercept-irinotecan combination. When no more options are available, regorafenib monotherapy should be the following choice. Combinations of anti-VEGF and anti-EGFR treatment have no place in this approach and are not indicated.

Review of systemic therapies for locally advanced and metastatic rectal cancer

Rectal cancer, along with colon cancer, is the second leading cause of cancer-related deaths in the U.S. Up to a quarter of patients have metastatic disease at diagnosis and 40% will develop metastatic disease. The past 10 years have been extremely exciting in the treatment of both locally advanced and metastatic rectal cancer (mRC). With the advent of neoadjuvant chemoradiation, increased numbers of patients with locally advanced rectal cancer (LARC) are surviving longer and some are seeing their tumors shrink to sizes that allow for resection. The advent of biologics and monoclonal antibodies has propelled the treatment of mRC further than many could have hoped. Combined with regimens such as FOLFOX or FOLFIRI, median survival rates have been increased to an average of 23 months. However, the combinations of chemotherapy regimens seem endless for rectal cancer. We will review the major chemotherapies available for locally advanced and mRC as well as regimens currently under investigation such as FOLFOXIRI. We will also review vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) inhibitors as single agents and in combination with traditional chemotherapy regimens.

Integrating systemic and surgical approaches to treating metastatic colorectal cancer

Multiple new treatment options for metastatic colorectal cancer have been developed over the past 2 decades, including conventional chemotherapy and agents directed against vascular endothelial growth factor and epidermal growth factor receptor. Combination regimens, integrated with surgical approaches, have led to an increase in median survival, and a minority of patients with resectable disease can survive for years. Clinical decision-making therefore requires a strategic, biomarker-based multidisciplinary approach to maximize life expectancy and quality of life. This review describes systemic approaches to the treatment of patients with metastatic colorectal cancer, including integration with liver resection, other liver-directed therapies, and primary resection.

The role of antiangiogenic agents in the treatment of patients with advanced colorectal cancer according to K-RAS status

Colorectal cancer (CRC) is the fourth most commonly diagnosed cancer worldwide. Recently, it has been found that about 40 % of patients with CRC have mutations in the K-RAS gene. Several clinical trials have showed that patients with metastatic colorectal cancer (mCRC) who present tumour-promoting mutations in signalling pathways involving the epidermal growth factor receptor (EGFR), which includes activating K-RAS mutations, do not respond to anti-EGFR drugs such as panitumumab and cetuximab. Hence, K-RAS status is now considered an important negative predictive factor for response to anti-EGFR drugs. Moreover, K-RAS status seems to have also a prognostic role in CRC, but this fact is somewhat controversial. Activity of antiangiogenic agents seems not to be influenced by K-RAS gene status. Tumour angiogenesis has attracted interest in attempts to improve the management of mCRC. The vascular endothelial growth factor (VEGF) pathway is fundamental to the regulation of angiogenesis, and research has focused on developing agents that selectively target it. In this way, the anti-VEGF antibody bevacizumab in combination with chemotherapy has provided important clinical benefits in terms of response rate, progression-free survival and overall survival to patients with mCRC. Efficacy data of bevacizumab in K-RAS wild-type patients seem to be comparable with the efficacy data observed with anti-EGFR therapies in a cross-trial comparison. Although there is a lack of prospective and randomized data in this setting, the combination of chemotherapy plus antiangiogenic agents could be considered as an effective alternative for the treatment of mCRC with independence of K-RAS gene status. Here, we review the available data we have in the literature of the use of antiangiogenic strategies in the treatment of mCRC nowadays.

Management of locally advanced and metastatic colon cancer in elderly patients

Colon cancer is the second leading cause of cancer mortality in the United States with a median age at diagnosis of 69 years. Sixty percent are diagnosed over the age of 65 years and 36% are 75 years or older. At diagnosis, approximately 58% of patients will have locally advanced and metastatic disease, for which systemic chemotherapy has been shown to improve survival. Treatment of cancer in elderly patients is more challenging due to multiple factors, including disabling co-morbidities as well as a decline in organ function. Cancer treatment of elderly patients is often associated with more toxicities that may lead to frequent hospitalizations. In locally advanced disease, fewer older patients receive adjuvant chemotherapy despite survival benefit and similar toxicity when compared to their younger counterparts. A survival benefit is also observed in the palliative chemotherapy setting for elderly patients with metastatic disease. When treating elderly patients with colon cancer, one has to consider drug pharmacokinetics and pharmacodynamics. Since chronological age is a poor marker of a patient’s functional status, several methods of functional assessment including performance status and activities of daily living (ADL) or instrumental ADL, or even a comprehensive geriatric assessment, may be used. There is no ideal chemotherapy regimen that fits all elderly patients and so a regimen needs to be tailored for each individual. Important considerations when treating elderly patients include convenience and tolerability. This review will discuss approaches to the management of elderly patients with locally advanced and metastatic colon cancer.

A systematic review of salvage therapy to patients with metastatic colorectal cancer previously treated with fluorouracil, oxaliplatin and irinotecan +/- targeted therapy

Oxaliplatin, irinotecan and 5-fluorouracil in combination with or without targeted therapies are well-documented treatment options for first- and second-line treatments of metastatic colorectal cancer. However, there are much less data on the beneficial effect on systemic therapy in the third-line setting. We therefore performed a systematic review of the current literature on third or later lines of treatment to patients with metastatic colorectal cancer after the use of approved drugs or combinations.

METHODS

A computer-based literature search was carried out using Pubmed and data reported at international meetings. Original studies reporting ≥15 patients who had previously received 5-fluorouracil, oxaliplatin and irinotecan were included. Furthermore, patients with KRAS wild type tumours should had received EGFR-directed therapy.

RESULTS

Conventional chemotherapeutic agents as capecitabine, mitomycin C, and gemcitabine have limited or no activity. Retreatment with oxaliplatin might be an option in selected patients. In addition, rechallenge with EGFR-directed therapy might be a valuable strategy. Data also suggest that angiogenetic drugs may postpone further progression and prolong survival. Lately, regorafinib has been approved. In conclusion, our current knowledge is based on many retrospective studies, some phase II studies and very few randomized clinical trials. Further prospective phase III trials comparing an investigational drug or combination with best supportive care in third- or later lines of treatment in metastatic colorectal cancer are highly warranted. Identification of predictive biomarkers and improvement of our understanding of molecular mechanisms is crucial.

Options for metastatic colorectal cancer beyond the second line of treatment

Colorectal cancer is the third most common cancer, with recent advances in the management of unresectable metastatic lesions. The aim of this review is to discuss the remaining options for heavily pretreated patients with unresectable metastatic colorectal cancer. Beyond second-line treatment, two epidermal growth factor receptor (EGFR) inhibitors, cetuximab and panitumumab, have a demonstrated clinical interest in patients with KRAS wild-type tumours. However, few data exist in patients pretreated with an anti-EFGR and who are being rechallenged with anti-EGFR drugs. Reintroduction of chemotherapy should be considered. In September 2012, regorafenib, a multi-kinase inhibitor was approved by the US Federal Drug Administration for patients refractory to other standard treatments. In the case of metastases limited to the liver, transarterial chemoembolization, hepatic artery infusion and radioembolization could also be discussed in selected patients. With the multiplication of therapeutic options in first-line, second-line treatment, and beyond, the concept of subsequent lines of chemotherapy should be replaced by a multiline strategy, dependent on the patient and on tumour biology. A better understanding of the tumour biology and predictive factors for the response to these therapies is needed, and further strategic trials are urgently warranted.

Efficacy and safety of bevacizumab plus chemotherapy in Chinese patients with metastatic colorectal cancer: a randomized phase III ARTIST trial

The efficacy and safety of bevacizumab with modified irinotecan, leucovorin bolus, and 5-fluorouracil intravenous infusion (mIFL) in the first-line treatment of metastatic colorectal cancer (mCRC) has not been well evaluated in randomized clinical trials in Chinese patients. We conducted a phrase III trial in which patients with previously untreated mCRC were randomized 2:1 to the mIFL [irinotecan (125 mg/m²), leucovorin (20 mg/m²) bolus, and 5-fluorouracil intravenous infusion (500 mg/m²) weekly for four weeks every six weeks] plus bevacizumab (5 mg/kg every two weeks) group and the mIFL group, respectively. Co-primary objectives were progression-free survival (PFS) and 6-month PFS rate. In total, 214 patients were enrolled. Our results showed that addition of bevacizumab to mIFL significantly improved median PFS (4.2 months in the mIFL group vs. 8.3 months in the bevacizumab plus mIFL group, P < 0.001), 6-month PFS rate (25.0% vs. 62.6%, P < 0.001), median overall survival (13.4 months vs. 18.7 months, P = 0.014), and response rate (17% vs. 35%, P = 0.013). Grades 3 and 4 adverse events included diarrhea (21% in the mIFL group and 26% in the bevacizumab plus mIFL group) and neutropenia (19% in the mIFL group and 33% in the bevacizumab plus mIFL group). No wound-healing complications or congestive heart failure occurred. Our results suggested that bevacizumab plus mIFL is effective and well tolerated as first-line treatment for Chinese patients with mCRC. Clinical benefit and safety profiles were consistent with those observed in pivotal phase III trials with mainly Caucasian patients.

Bevacizumab plus chemotherapy as salvage treatment in chemorefractory patients with metastatic colorectal cancer

Purpose

The combination of chemotherapy and bevacizumab, a monoclonal antibody targeting the vascular endothelial growth factor, is consistently being used as first- and second-line treatment in patients with metastatic colorectal cancer (mCRC). There is little data of the activity of bevacizumab in chemorefractory mCRC patients. The aim of this retrospective single center study was to evaluate the activity of bevacizumab combined with chemotherapy in this study population.

Methods

Forty-six consecutive mCRC patients treated in the University Hospital Gasthuisberg (Leuven, Belgium) receiving bevacizumab in advanced lines following failure of conventional chemotherapy were included in this study. Treatment regimen consisted of bevacizumab 5 mg/kg in combination with leucovorin, 5-fluorouracil, and oxaliplatin (FOLFOX) or leucovorin, 5-fluorouracil, and irinotecan (FOLFIRI).

Results

Bevacizumab plus chemotherapy was used in third-line treatment in eight (17%) patients and in fourth-line treatment or more in 38 patients (83%). All patients previously failed irinotecan-based chemotherapy, 44 (96%) failed oxaliplatin-based regimens, and 40 (87%) failed treatment with cetuximab. Bevacizumab was given in combination with irinotecan-based chemotherapy in 36 patients, oxaliplatin-based chemotherapy in nine patients, and with single agent 5-fluorouracil in one patient. Objective response was demonstrated in ten patients (22%) and disease control in 38 (83%) with a median progression-free survival of 8.9 months and a median overall survival of 13.8 months. Only four patients experienced grade III and above bevacizumab-related toxicity.

Conclusion

Taking into account the retrospective nature of the study which can influence the selection of patients, bevacizumab given in advanced lines after failure of conventional chemotherapy and antiepidermal growth factor receptor agents can result in high disease control rates in patients with mCRC.

Dynamics of circulating endothelial cells and endothelial progenitor cells in breast cancer patients receiving cytotoxic chemotherapy

BACKGROUND

The abundance of circulating endothelial cells (CECs) and circulating endothelial progenitor cells (CEPs), which serve as surrogate markers for angiogenesis, may be affected by chemotherapy. We studied their dynamic change during consecutive cycles of chemotherapy.

METHODS

We collected blood samples from 15 breast cancer patients, who received a total of 56 courses of systemic chemotherapy, and measured the CECs, viable CECs (V-CECs), and CEPs by six-color flow cytometry within the seven days prior to chemotherapy, twice a week during the first and second cycles of chemotherapy, and then once a week during the subsequent cycles.

RESULTS

The CEC, V-CEC, and CEP levels all significantly decreased from day 1 of treatment to the first week of chemotherapy. After one week of chemotherapy, the CEC and V-CEC levels returned to a level similar to day 1. The CEP level remained significantly reduced after the first week of chemotherapy, but gradually rebounded until the next course of chemotherapy. After six cycles of chemotherapy, the total number of CEC and V-CEC cells trended toward a decrease and the CEP cells toward an increase. Clinical factors, including the existence of a tumor, chemotherapy regimens, and the use of granulocyte colony stimulating factor, did not significantly affect these results.

CONCLUSIONS

The CEC and CEP counts change dynamically during each course of chemotherapy and after the chemotherapy cycles, providing background data for any future study planning to use CECs and CEPs as surrogate markers of angiogenesis in antiangiogenesis treatments combined with chemotherapy.

Bevacizumab-containing regimens after cetuximab failure in Kras wild-type metastatic colorectal carcinoma

Bevacizumab and cetuximab both improve treatment efficacy when administered with chemotherapy for metastatic colorectal carcinoma (mCRC). Cetuximab has enhanced efficacy in Kras wild-type tumors. However, inferior outcomes have been demonstrated concerning the concurrent use of bevacizumab and cetuximab with chemotherapy. There is an urgent need to define the optimal sequence of use of these two agents. With regard to the pre-clinical data that increased VEGF expression is associated with acquired resistance to anti-EGFR antibody, we performed a retrospective analysis on the outcomes of patients who received bevacizumab-containing regimens after cetuximab failure in Kras wild-type mCRC. From January 2006 to December 2011, patients who received bevacizumab-containing regimens for mCRC in our institution were reviewed. Patients were eligible for further analysis if the following criteria were met: i) Kras wild-type mCRC; ii) chemotherapy and cetuximab received as immediate prior treatment; iii) chemotherapy and bevacizumab received as the index line of treatment; and iv) imaging conducted for response evaluation. Outcome measures included median progression-free survival (mPFS) and objective response rate (ORR). Targeted adverse events were recorded in accordance with two prospective observational cohort studies; the BRiTE and BEAT studies. Fifty patients who received bevacizumab-containing regimens were reviewed and 18 of them met the criteria for further analysis. After a median follow-up of 12.1 months, the mPFS for the total group of patients was 26.3 weeks (95% CI, 19.5–33.0 weeks) with an ORR of 38.9%. Two patients (11.1%) had hypertension that required additional anti-hypertensive drugs and one patient did not survive due to a bowel perforation. No arterial thromboembolic events (ATEs), post-operative wound-healing complications (POWHCs) or grade III/IV bleeding were observed. In patients with Kras wild-type mCRC, bevacizumab-containing regimens following cetuximab failure have modest activity and manageable toxicity.

Therapeutic antibodies against cancer

Antibody-based therapeutics against cancer are highly successful and currently enjoy unprecedented recognition of their potential; 13 monoclonal antibodies (mAbs) have been approved for clinical use in the European Union and in the United States. Bevacizumab, rituximab, and trastuzumab had sales in 2010 of more than $5 billion each. Hundreds of mAbs, including bispecific mAbs and multispecific fusion proteins, mAbs conjugated with small-molecule drugs, and mAbs with optimized pharmacokinetics, are in clinical trials. However, deeper understanding of mechanisms is needed to overcome major problems including resistance to therapy, access to targets, complexity of biological systems, and individual variations.

Capecitabine and bevacizumab in heavily pre-treated patients with advanced colorectal cancer

BACKGROUND

No standard treatment exists for patients with metastatic colorectal cancer who have progressed after treatment with 5-fluorouracil (5-FU), oxaliplatin, irinotecan and an anti-EGFR antibody. The efficacy and safety of bevacizumab and capecitabine in heavily pre-treated patients with metastatic colorectal cancer were evaluated.

PATIENTS AND METHODS

Patients with metastatic colorectal cancer, who had been exposed to 5-FU, oxaliplatin, and irinotecan in the first- and second line setting and mainly with irinotecan and cetuximab as third line treatment, were treated with capecitabine and bevacizumab. Four patients had received bevacizumab earlier.

RESULTS

From January 2009 to August 2010 34 patients started treatment with capecitabine and bevacizumab. The combination was well tolerated. Progression free survival was 5.4 months and median overall survival was 12.2 months.

CONCLUSION

The combination of capecitabine and bevacizumab was safe with an acceptable toxicity profile and induced a significant rate of disease control in heavily pre-treated patients with metastatic colorectal cancer.

Biologic therapies in the metastatic colorectal cancer treatment continuum--applying current evidence to clinical practice

More therapeutic options are now available than ever before for patients with metastatic colorectal cancer (mCRC) and, as such, treatment decisions have become more complex. A multidisciplinary approach is, therefore, required to effectively manage these patients. In the past few years, many trials have reported on the value of combining biological agents, such as those targeting vascular endothelial growth factor A and epidermal growth factor receptors, with chemotherapy. However, despite the plethora of information now available, the optimal treatment strategy for patients with mCRC remains unclear. Indeed, the propensity of investigators to conduct clinical trials utilising a variety of chemotherapy backbones combined with the increased complexity of retrospectively incorporating analyses of genetic mutation status (e.g. KRAS and BRAF) have led to conflicting results for seemingly similar endpoints, particularly overall survival. As a result, guidelines that have been developed, whilst having some similarities, have distinct differences in terms of suggested therapeutic combinations. Therefore, here, we review and distil the currently available data reported from phase III trials of biologic agents in the first-, second- and third-line mCRC settings.

Bevacizumab combined with chemotherapy in the second-line treatment of metastatic colorectal cancer: results from the phase II BEVACOLOR study

BACKGROUND

This prospective phase II study assessed the efficacy and safety of bevacizumab plus chemotherapy regimens commonly used in the second-line treatment of metastatic colorectal cancer (mCRC).

METHODS

Patients with mCRC who progressed or relapsed after first-line oxaliplatin-based or irinotecan-based treatment received bevacizumab 2.5 mg/kg/week plus chemotherapy until disease progression. The primary endpoint was disease-control rate (DCR). Secondary endpoints included progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and safety.

RESULTS

Fifty-three patients (66% men; median age, 62 years old) received second-line bevacizumab plus folinic acid, fluorouracil, and irinotecan (FOLFIRI; 57%), folinic acid, fluorouracil, oxaliplatin (FOLFOX; 26%), irinotecan (15%), or capecitabine plus irinotecan (XELIRI; 2%). The DCR was 87% (95% CI, 77%-97%); ORR was 32% (95% CI, 19%-46%). Median PFS was 6.5 months (95% CI, 5.8-7.8 months) and median OS 19.3 months, (95% CI, 14.2-25.1 months).The most frequent grade 3/4 adverse events included neutropenia (21%), diarrhea (15%), asthenia, and vomiting (9% each). Five patients (9%) had grade 3/4 targeted toxicities: grade 3 hypertension (n = 2), grade 3 venous thromboembolism (n = 2), and grade 4 arterial thromboembolism (n = 1). None of these events led to death during the study.

CONCLUSION

Bevacizumab plus standard second-line chemotherapy is highly active in patients with mCRC and has an acceptable safety profile.