Abstract PR03: Molecular profiling of advanced solid tumors at Princess Margaret Cancer Centre and patient outcomes with genotype-matched clinical trials

Accelerating Therapeutic Development through Innovative Trial Design in Colorectal Cancer

OPINION STATEMENT

Current trial design is challenged by the advancement of technologies that have enabled deeper understanding of the molecular drivers of colorectal cancer (CRC). The speed of trial testing and the ability to test larger volumes of promising novel agents in the face of smaller populations identified by molecular profiling are challenges posed to clinical studies. Master protocols that utilize umbrella designs are equipped to deal with potential biomarker and matched treatments simultaneously. Although complex in nature, they increase trial efficiency by utilizing shared screening platforms, test multiple treatments together, and simplify regulatory submission and reporting under a common protocol. Emerging technologies such as circulating tumor DNA (ctDNA) may help speed up adjuvant trials. These studies have been traditionally slow to complete due to low event rates and the high numbers needed to recruit. ctDNA used as a surrogate for minimal residual disease (MRD) and as an early marker of relapse may help counter some of these factors that deter innovation in this setting. Finally, in the era of precision medicine, surgery should not be forgotten as the only potentially curative option to date in metastatic disease. Five-year overall survival following resection of liver metastasis exceeds what can be achieved with chemotherapy alone in selected cases. Surgical advances have lowered morbidity and allow for greater resection volumes and repeated interventions. Although historically challenging, a well-designed randomized surgical intervention trial would greatly facilitate moving single-institution guidelines reported by case series into wider clinical practice.

Precision oncology using a clinician-directed, tailored approach to molecular profiling

AIM

Precision oncology involves molecularly matching patients to targeted agents usually in early drug development (EDD) programs. Molecular profiling (MP) identifies actionable targets. Comprehensive commercial MP platforms are costly and in resource limited environments, a more practical approach to MP is necessary to support EDD and precision oncology. We adopted a clinician-directed, tailored approach to MP to enrol patients onto molecularly targeted trials. We report the feasibility of this approach.

METHODS

All patients referred to the Royal Melbourne Hospital (RMH) EDD between September 2013 and September 2015 were identified in a prospective database. Key captured data included clinicopathological data, MP platform ordered (if any), molecular targets identified and subsequent enrolment onto clinical trials. EDD-clinician decisions to order MP and the platform utilized was guided by patient consultation, tumor type, trial availability and requirement for molecular information.

RESULTS

We identified 377 patients referred to RMH EDD. A total of 216 (57%) had MP ordered. The remainder had known actionable targets (19%), or were inappropriate for clinical trials (24%). In those undergoing MP, 187 genetic aberrations were found in 113 patients with 98 considered actionable targets in 86 patients. Ninety-eight (25%) patients were enrolled onto a clinical trial, including 40 (11%) receiving molecularly matched treatments. Median progression-free survival was improved in patients enrolled onto molecularly matched trials compared to those on unmatched trials (3.6 months vs 1.9 months, HR 0.58 [0.38-0.89], P  =  0.013).

CONCLUSION

A clinician-directed, tailored approach to the use of MP is feasible, resulting in 11% of patients enrolled onto molecularly matched trials.