Extended RAS Analysis of the Phase III EPIC Trial: Irinotecan + Cetuximab Versus Irinotecan as Second-Line Treatment for Patients with Metastatic Colorectal Cancer

Drug combinations of camptothecin derivatives promote the antitumor properties

Camptothecin (CPT) derivatives are widely used as small molecule chemotherapeutic agents and have demonstrated efficacy in the treatment of diverse solid tumors. A variety of derivatives have been developed to resolve the drawbacks of poor water solubility, high toxicity and rapid hydrolysis in vivo. However, the obstacles, such as acquired resistance and toxicity, still exist. The utilization of rational drug combinations has the potential to enhance the efficacy and mitigate the toxicity of CPT derivatives. This paper provides an overview of CPT derivatives in combination with other drugs, with a particular focus on cell cycle inhibitors, DNA synthesis inhibitors, anti-metastatic drugs and immunotherapy agents. Concurrently, the mechanisms of antitumor activity of combinations of different classes of drugs and CPT derivatives are elucidated. While the various combination strategies have yielded more favorable therapeutic outcomes, the efficacy and toxicity of the drug combinations are influenced by the inherent properties of the drugs involved. Moreover, a summary of the drug conjugates of CPT derivatives was provided, accompanied by an analysis of the structural activity relationship (SAR). This paves the way for the subsequent developments in drug combinations and delivery modes.

Targeting the EGFR signalling pathway in metastatic colorectal cancer

Epidermal growth factor receptor (EGFR) and its activated downstream signalling pathways play a crucial role in colorectal cancer development and progression. After four decades of preclinical, translational, and clinical research, it has been shown that blocking the EGFR signalling pathway at different molecular levels represents a fundamental therapeutic strategy for patients with metastatic colorectal cancer. Nevertheless, the efficacy of molecularly targeted therapies is inescapably limited by the insurgence of mechanisms of acquired cancer cell resistance. Thus, in the era of precision medicine, a deeper understanding of the complex molecular landscape of metastatic colorectal cancer is required to deliver the best treatment choices to all patients. Major efforts are currently ongoing to improve patient selection, improve the efficacy of available treatments targeting the EGFR pathway, and develop novel combination strategies to overcome therapy resistance within the continuum of care of metastatic colorectal cancer.

Second-line treatment strategies for RAS wild-type colorectal cancer: A systematic review and Network Meta-analysis (NMA)

BACKGROUND

The optimal strategy for second-line (IIL) treatment in KRAS wt metastatic colorectal cancer (mCRC) is not determined yet.

METHODS

A random-effect NMA of phase II/III RCTs was conducted to evaluate IIL treatment for all-RAS wt mCRC, comparing anti-EGFR or anti-VEGF, and chemotherapy (CT).

RESULTS

Overall, 11 RCTs (3613 patients) were included. In KRAS wt patients, PFS was improved with anti-VEGF (HR 0.43) and anti-EGFR (HR 0.63) vs CT. However, anti-VEGF based therapy had the highest likelihood of being ranked as the best treatment in terms of PFS (SUCRA 99.3%) and OS (SUCRA 99.4%). Bevacizumab-based treatment is most likely to be the best treatment in terms of PFS (SUCRA 89.1%) and OS (SUCRA 86.7%).

CONCLUSIONS

Second line treatment with anti-VEGF and anti-EGFR improved PFS in mCRC patients, however, anti-VEGF based therapy, particularly CT plus bevacizumab, is the best treatment according to SUCRA in terms of PFS and OS.

Cardiotoxicity induced by fluoropyrimidine drugs in the treatment of gastrointestinal tumors

In this editorial, we review the article published in World J Gastrointest Oncol 2019, 11: 1031-1042. We specifically focus on the occurrence, clinical characteristics, and risk factors of fluoropyrimidine drug-related cardiotoxicity in patients with gastrointestinal tumors. Despite significant advancements in diagnostic and therapeutic techniques that have reduced mortality rates associated with digestive system tumors, the incidence and mortality rates of treatment-related cardiotoxicity have been increasing, severely impacting the survival and prognosis of cancer patients. Fluoropyrimidine drugs are widely used as antimetabolites in the treatment of malignant tumors, including gastrointestinal tumors, and they represent the second largest class of drugs associated with cardiotoxicity. However, there is often a lack of awareness or understanding regarding their cardiotoxic effects and associated risks.

The effective combination therapies with irinotecan for colorectal cancer

Colorectal cancer is the third most common type of cancer worldwide and has become one of the major human disease burdens. In clinical practice, the treatment of colorectal cancer has been closely related to the use of irinotecan. Irinotecan combines with many other anticancer drugs and has a broader range of drug combinations. Combination therapy is one of the most important means of improving anti-tumor efficacy and overcoming drug resistance. Reasonable combination therapy can lead to better patient treatment options, and inappropriate combination therapy will increase patient risk. For the colorectal therapeutic field, the significance of combination therapy is to improve the efficacy, reduce the adverse effects, and improve the ease of treatment. Therefore, we explored the clinical advantages of its combination therapy based on mechanism or metabolism and reviewed the rationale basis and its limitations in conducting exploratory clinical trials on irinotecan combination therapy, including the results of clinical trials on the combination potentiation of cytotoxic drugs, targeted agents, and herbal medicine. We hope that these can evoke more efforts to conduct irinotecan in the laboratory for further studies and evaluations, as well as the possibility of more in-depth development in future clinical trials.

Molecular and genetic targets within metastatic colorectal cancer and associated novel treatment advancements

Colorectal cancer results in the deaths of hundreds of thousands of patients worldwide each year, with incidence expected to rise over the next two decades. In the metastatic setting, cytotoxic therapy options remain limited, which is reflected in the meager improvement of patient survival rates. Therefore, focus has turned to the identification of the mutational composition inherent to colorectal cancers and development of therapeutic targeted agents. Herein, we review the most up to date systemic treatment strategies for metastatic colorectal cancer based on the actionable molecular alterations and genetic profiles of colorectal malignancies.

Biweekly cetuximab in combination with capecitabine and oxaliplatin (XELOX) or irinotecan (XELIRI) in the first-line and second-line treatment of patients with RAS wild-type metastatic colorectal cancer

Background

Oral capecitabine in combination with intravenous oxaliplatin (XELOX) or irinotecan (XELIRI) are acceptable substitutions to fully intravenous regimens. Biweekly (as opposed to weekly) cetuximab is more convenient when combined with biweekly chemotherapy. Here, we report the tolerability and efficacy of biweekly cetuximab in combination with biweekly XELOX or XELIRI in patients with RAS wild-type metastatic colorectal cancer (RAS-WT mCRC).

Methods

Clinical data of consecutive patients with mCRC who received biweekly cetuximab (500 mg/m²) in combination with XELOX or XELIRI between January 2009 and May 2019 in the first- or second-line settings was extracted. Dosage of XEL (Capecitabine/XELODA) was 1,000 mg/m² twice daily for 9 days, plus on day 1 oxaliplatin 85 mg/m² or irinotecan 180 mg/m². Treatment dose reduction and delay for ≥7 days was analysed as surrogates for toxicity. Extended RAS testing was performed in the context of this study for patients who received treatment based on limited KRAS-WT genotype.

Results

Sixty one patients with RAS-WT mCRC fulfilled the eligibility criteria. XELOX was administered to 26 (42.6%) and XELIRI to 35 (57.4%) of patients. For all patients in the first-line setting, the objective response rate (ORR), median progression free survival (PFS) and median overall survival (OS) were 54%, 8 months and 25 months, respectively. The corresponding outcomes for the subgroup of patients who received first-line XELOX were 68%, 10 months and not reached, respectively. For all patients in the second-line setting, the ORR, PFS and OS were 50%, 7 months and 20 months, respectively. Chemotherapy components dose reduction and delays were observed in 18 (29.5%) and 25 (41%) patients, respectively. The corresponding frequencies for cetuximab were 3 (5%) and 31 (50.8%).

Conclusion

Biweekly cetuximab in combination with XELOX or XELIRI is tolerable and effective. The addition of cetuximab to capecitabine and oxaliplatin is associated with favourable outcome.

Real-world overall survival of patients receiving cetuximab in later lines of treatment for metastatic colorectal cancer

Aim: To examine characteristics of and treatment duration and real-world overall survival (rwOS) in patients receiving cetuximab as second-line (2L) or third-line (3L) treatment for metastatic colorectal cancer. Materials & methods: This was a retrospective study of 1096 and 684 patients in 2L and 3L cohorts, respectively. Results: The most common cetuximab-based regimens were cetuximab + folinic acid, fluorouracil and irinotecan (2L: 44%; 3L: 32%) and cetuximab + irinotecan (2L: 28%; 3L: 35%). Kaplan-Meier survival estimates and stepwise Cox regression model analysis demonstrated median treatment duration and rwOS of 3.7 and 14.4 months, respectively, in patients receiving treatment in the 2L cohort. In the 3L cohort, treatment duration was 3.3 months and rwOS was 12.0 months. Conclusion: This large real-world study provides evidence of rwOS in patients with metastatic colorectal cancer receiving cetuximab-based regimens as 2L or 3L treatment.

Cardiovascular Risks with Epidermal Growth Factor Receptor (EGFR) Tyrosine Kinase Inhibitors and Monoclonal Antibody Therapy

PURPOSE OF REVIEW

Tyrosine kinase inhibitors (TKI) and monoclonal antibodies (mAbs) that target the epidermal growth factor receptor (EGFR) have changed the therapeutic landscape across a range of solid malignancies. However, there is little data regarding the cardiovascular (CV) impact of these agents. The purpose of this review is to discuss reported CV effects, pathophysiology, pre-treatment screening, diagnostic workup, and treatment recommendations in this patient population.

RECENT FINDINGS

It is apparent that CV events are not class dependent, and while infrequently reported in clinical trials, unique CV toxicity may occur with EGFR inhibitors, including structural, electrical, and vascular events. There remains an unmet need to fully elucidate the spectrum of CV events associated with EGFR inhibitors. Early CV screening, close clinical monitoring, coupled with a multidisciplinary approach between medical and cardio-oncology is needed to minimize the potentially detrimental impact of cardiotoxicity in this patient population.

Treatments after first progression in metastatic colorectal cancer. A literature review and evidence-based algorithm

Prolonging survival, achieving symptoms palliation and preserving quality of life are the primary therapeutic goals of treatments administered after disease progression in mCRC. Even if the impact of these therapies on the prognosis of affected patients is less relevant than the impact of the upfront treatment, tailoring the optimal second-line therapy is increasingly important. Several therapeutic options are available, and different factors including not only patient- and disease-related characteristics, but also the first-line treatment received (i.e., type, timing of disease progression, observed outcome and reported toxicities) may drive this choice. Herein, we describe the current state of the art in the landscape of treatments after progression in mCRC. Based on a critical review of the literature, we built a patient-oriented therapeutic algorithm, aiming to guide clinicians in their daily decision-making.