An analysis of research biopsy core variability from over 5000 prospectively collected core samples

Factors correlated with biopsy tissue adequacy and the prevalence of within-biopsy variability were evaluated. Totally, 1149 research biopsies were performed on 686 patients from which 5090 cores were assessed. Biopsy cores were reviewed for malignant percentage (estimated percentage of cells in the core that were malignant) and malignant area (estimated area occupied by malignant cells). Linear mixed models and generalized linear mixed models were used for the analysis. A total of 641 (55.8%) biopsies contained a core with <10% malignant percentage (inadequate core). The chance of an inadequate core was not influenced by core order, though the malignant area decreased with each consecutive core (p < 0.001). Younger age, bone biopsy location, appendiceal tumor pathology, and responding/stable disease prior to biopsy increased the odds of a biopsy containing zero adequate cores. Within-biopsy variability in core adequacy is prevalent and suggests the need for histological tumor quality assessment of each core in order to optimize translational analyses.

Underreporting of Research Biopsies from Clinical Trials in Oncology

Purpose: Research biopsies are frequently incorporated within clinical trials in oncology and are often a mandatory requirement for trial enrollment. However, limited information is available regarding the extent and completeness of research biopsy reporting.Experimental Design: We identified a cohort of therapeutic clinical trials where research biopsies were performed between January 2005 and October 2010 from an IR database at our institution. Clinical trial protocols were compared with the highest level of corresponding publication as a manuscript or registry report.Results: A total of 866 research biopsies were performed across 46 clinical trials, with a median of 8 patients biopsied/trial and 19 biopsies collected/trial. After a median follow-up time of 4.3 years from trial completion, 36 of 46 trials (78%) reported trial results: published manuscripts (n = 35), or registry report (n = 1). A total of 635 conducted biopsies were reported in 18 of the 46 trials (39%). Six (33%) of these 18 trials underreported the number of biopsies performed. Of 33 trials with mandatory research biopsies, 13 (39%) trials reported on these biopsies. Biopsy complications occurred in 8 trials [n = 39 patients, 6 grade 3/4 adverse events (AE)] but only 1 trial reported these. Factors associated with biopsy reporting included a larger number of biopsies (P ≤ 0.001) and serial biopsies (P < 0.001). Twelve of 16 (75%) trials with >12 biopsies performed reported on these biopsies compared with only 20% (6/30) that performed ≤12 biopsies.Conclusions: Despite ethical obligations to report research biopsies, the majority (61%) of trials do not report results from research biopsies. Complications are rarely reported in these studies. Improved reporting of results and AEs from research biopsies is needed. Clin Cancer Res; 23(21); 6450-7. ©2017 AACR.

Enhancing value of clinical pharmacodynamics in oncology drug development: An alliance between quantitative pharmacology and translational science

Clinical pharmacodynamic evaluation is a key component of the "pharmacologic audit trail" in oncology drug development. We posit that its value can and should be greatly enhanced via application of a robust quantitative pharmacology framework informed by biologically mechanistic considerations. Herein, we illustrate examples of intersectional blindspots across the disciplines of quantitative pharmacology and translational science and offer a roadmap aimed at enhancing the caliber of clinical pharmacodynamic research in the development of oncology therapeutics.

Critical parameters in targeted drug development: the pharmacological audit trail

The Pharmacological Audit Trail (PhAT) comprises a set of critical questions that need to be asked during discovery and development of an anticancer drug. Key aspects include: (1) defining a patient population; (2) establishing pharmacokinetic characteristics; (3) providing evidence of target engagement, pathway modulation, and biological effect with proof of concept pharmacodynamic biomarkers; (4) determining intermediate biomarkers of response; (5) assessing tumor response; and (6) determining how to overcome resistance by combination or sequential therapy and new target/drug discovery. The questions asked in the PhAT should be viewed as a continuum and not used in isolation. Different drug development programmes derive different types of benefit from these questions. The PhAT is critical in making go-no-go decisions in the development of currently studied drugs and will continue to be relevant to discovery and development of future generations of anticancer agents.