Related Experiment Video
Updated: Dec 25, 2025

Quadruple-Checkerboard: A Modification of the Three-Dimensional Checkerboard for Studying Drug Combinations
Published on: July 24, 2021
A critical evaluation of methods to interpret drug combinations
Nathaniel R Twarog1, Michele Connelly1, Anang A Shelat2
1Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN, 38105, USA.
Traditional combination therapy analysis methods are unreliable. The BRAID response-surface method offers a more stable and accurate approach for analyzing drug interactions, revealing new therapeutic strategies in cancer research.
Area of Science:
- Pharmacology
- Biostatistics
- Cancer Research
Background:
- Combination therapy is crucial in modern medicine, but its analysis presents challenges.
- Existing methods for analyzing drug combinations are susceptible to noise and bias.
- Robust and reliable analysis is needed to support scientific conclusions in combination studies.
Purpose of the Study:
- To compare traditional index methods with response-surface approaches for combination analysis.
- To demonstrate the stability and accuracy of the BRAID method using simulated and real-world data.
- To identify novel therapeutic combinations and mechanisms of action in cancer.
Main Methods:
- Utilized simulated and real-world combination datasets.
- Applied traditional index methods and the BRAID response-surface method for analysis.
- Evaluated methods based on stability, bias, and accuracy in discriminating interaction types.
Main Results:
- Traditional index methods were found to be unstable and biased by experimental conditions.
- The BRAID method demonstrated greater consistency and lack of bias.
- BRAID more accurately captured compound mechanism of action and interaction types (synergistic, antagonistic, additive).
Conclusions:
- The BRAID method is a superior approach for analyzing drug combinations compared to traditional methods.
- BRAID analysis revealed enhanced AKT sensitivity in specific cancer cell lines.
- BRAID identified a broader range of PARP inhibitor combination therapies for BRCA1-deficient cancers.
Related Concept Videos
Agonism and Antagonism: Quantification
To quantify these effects, researchers use a dose-response curve, which provides valuable information about the potency and efficacy of a drug. Potency refers to...
Combined Effects of Drugs: Synergism
Such synergistic combinations...
Combined Effects of Drugs: Antagonism
The most common type is receptor antagonism, where one drug acts as an antagonist to block the effects of another drug by...
Measurement of Bioavailability: Pharmacodynamic Methods
Therapeutic Drug Monitoring: Drug Analysis Methods
Dosage Regimens: Designs and Approaches

