Effectiveness of bevacizumab and cetuximab in metastatic colorectal cancer across selected public hospitals in Queensland

Research governance authorisation: the next frontier

Objective There is much interest in examining the use of medicines and their real-world benefits and harms using routinely collected data sources such as patients' electronic medical records in hospitals in order to optimise use and health outcomes. This study aimed to describe the process and challenges involved in obtaining ethical approval and research governance authorisation for a research project that started on 7 December 2018 in Queensland and make recommendations for improving the process. Methods There were three aspects: (a) ethics approval; (b) governance - site-specific assessment (SSA); and (c) governance - Public Health Act (PHA) Application Assessment. Results The process to satisfy all requirements took more than 1 year (371 days); ethics took 16 days and PHA approval 16 days. The major hurdle was the SSA, which took 98-274 days across five sites. The main issues were opaqueness in processes and inconsistences in approach leading to considerable frustration. Discussion It is recommendeded that Research Governance Offices should be clear on the process and requirements. All Local Hospital Networks (LHN, Hospital and Health Services in Queensland) should develop and adopt a standardised low and negligible risk SSA approval process. Frustration of government officials and researchers led the National Health and Medical Research Council to streamline ethics approval processes, but the same cannot be said for the governance process. It is appreciated that LHN processes were developed for good and valid reasons, but the onerous and inconsistent application of these processes hinder timely and relevant research. It is time for action: follow the success of the ethics process to redesign governance. What is known about the topic? Researchers are interested in examining the use of medicines and their real-world benefits and harms using routinely collected data sources such as patients' electronic medical records in hospitals in order to optimise use and health outcomes. There are challenges in obtaining ethical approval and research governance authorisation for research projects. What does this paper add? We identified that the main hurdle was obtaining site-specific agreements across numerous hospital sites. What are the implications for practitioners? We recommend that Research Governance Offices should be clear on the process and requirements. All Local Hospital Networks (LHN, Hospital and Health Services in Queensland) should develop and adopt a standardised low and negligible risk SSA approval process. The ethics approval process has been streamlined in recent years so we need to follow this success to redesign governance.

First-line cetuximab versus bevacizumab for RAS and BRAF wild-type metastatic colorectal cancer: a systematic review and meta-analysis

BACKGROUND

A first-line biologic treatment for metastatic colorectal cancer (mCRC) is still controversial. We, therefore, performed a meta-analysis to determine the efficacy of first-line cetuximab versus bevacizumab for RAS and BRAF wild-type mCRC.

METHODS

In March 2018, an electronic search of the following biomedical databases was performed: PubMed, EMBASE, Cochrane Library, ClinicalTrials.gov and Web of Knowledge. Randomized controlled trials (RCTs) and prospective or observational cohort studies (OCSs) were included. Subgroup analyses of all RCTs were performed in all outcomes. All statistical analyses were performed using RevMan software 5.3.

RESULTS

Two RCTs and three OCSs, involving a total 2576 patients, were included. The meta-analysis reported that cetuximab was associated with a longer overall survival (OS) [HR 0.89, 95% CI (0.81-0.98); p = 0.02], a higher ORR [RR 1.11, 95% CI (1.03-1.19); p = 0.006], higher complete response [RR 3.21, 95% CI (1.27-8.12); p = 0.01] and a greater median depth of response than bevacizumab. However, no significant difference was observed between cetuximab and bevacizumab groups for PFS, DCR, partial response, progressive disease, curative intent metastasectomy, EORR and incidence of grade 3 or higher adverse events. In the subgroup meta-analyses of the RCTs, inconsistent results compared to the main analysis, however, were found, in the ORR, DCR and curative intent metastasectomy.

CONCLUSIONS

The current evidence indicates that compared to bevacizumab treatment, cetuximab provides a clinically relevant effect in first-line treatment against mCRC, at the cost of having lower stable disease.

EGFR Gene Amplification and KRAS Mutation Predict Response to Combination Targeted Therapy in Metastatic Colorectal Cancer

Genetic variability in KRAS and EGFR predicts response to cetuximab in irinotecan refractory colorectal cancer. Whether these markers or others remain predictive in combination biologic therapies including bevacizumab is unknown. We identified predictive biomarkers from patients with irinotecan refractory metastatic colorectal cancer treated with cetuximab plus bevacizumab. Patients who received cetuximab plus bevacizumab for irinotecan refractory colorectal cancer in either of two Phase II trials conducted were identified. Tumor tissue was available for 33 patients. Genomic DNA was extracted and used for mutational analysis of KRAS, BRAF, and p53 genes. Fluorescence in situ hybridization was performed to assess EGFR copy number. The status of single genes and various combinations were tested for association with response. Seven of 33 patients responded to treatment. KRAS mutations were found in 14/33 cases, and 0 responded to treatment (p = 0.01). EGFR gene amplification was seen in 3/33 of tumors and in every case was associated with response to treatment (p < 0.001). TP53 and BRAF mutations were found in 18/33 and 0/33 tumors, respectively, and there were no associations with response to either gene. EGFR gene amplification and KRAS mutations are predictive markers for patients receiving combination biologic therapy of cetuximab plus bevacizumab for metastatic colorectal cancer. One marker or the other is present in the tumor of half of all patients allowing treatment response to be predicted with a high degree of certainty. The role for molecular markers in combination biologic therapy seems promising.