By Jane Cook
March 9, 2022
Pembrolizumab: A Success Across Cancer Types
Drug repurposing is a well-established practice, where drugs that either failed in clinical trials for their intended endpoints or are approved for a different disease are trialed in a new context.
Following the blockbuster success of Merck’s cancer immunotherapy drug Keytruda (pembrolizumab) in its original approved use for NSCLC, the company has successfully tested the drug in numerous cancers with subsequent approval in seventeen cancer types and counting.
Biomarkers for Companion Diagnostics
What gives pembrolizumab an edge in efficacy and approval is the use of biomarkers for companion diagnostics, identifying the patients that will be most likely to have positive responses from treatment.
Merck has employed biomarkers since its initial clinical trials with pembrolizumab and continues to research the efficacy of the PD-L1 biomarker used primarily for pembrolizumab as well as identifying new biomarkers in different cancer types.
Predictors of Pembrolizumab Response in Urothelial Cancer
A recent study from Merck’s research team identified the biomarkers that best predict pembrolizumab treatment response in advanced urothelial cancer (UC). PD-L1 remains a strong predictor of positive response. Interestingly, two newer biomarkers also help predict positive outcomes: tumor mutational burden and infiltrating T cells. These two biomarkers apply more broadly to typical cancer biology, while PD-L1 is a good addition specifically for pembrolizumab.
Their study also found that certain signatures of stromal cells were negatively correlated with pembrolizumab, providing a good indicator for patients where a different therapeutic strategy may work better.
Trending Towards Multi-Dimensional Biomarkers
These results reflect the larger shift towards the use of multi-dimensional biomarkers in diagnostics. Including multiple markers of the status of the tumor microenvironment allows for a more integrated understanding of how a given drug is likely to perform, allowing for more improved treatment outcomes.
Identifying biomarkers is a challenging computational task. Outsourcing bioinformatic analyses to BaaS providers like experts at Bridge Informatics helps eliminate common challenges. Book a free discovery call with us to discuss your project needs.
Jane Cook, Journalist & Content Writer, Bridge Informatics
Jane is a Content Writer at Bridge Informatics, a professional services firm that helps biotech customers implement advanced techniques in the management and analysis of genomic data. Bridge Informatics focuses on data mining, machine learning, and various bioinformatic techniques to discover biomarkers and companion diagnostics. If you’re interested in reaching out, please email [email protected] or [email protected].