Bayesian optimization has been studied in many fields as a technique for global optimization of black-box functions. We applied these techniques for optimizing the formulation and manufacturing methods of pharmaceutical products to eliminate unnecessary experiments and accelerate method development tasks.
A simulation dataset was generated by the data augmentation from a design of experiment (DoE) which was executed to optimize the formulation and process parameters of orally disintegrating tablets. We defined a composite score for integrating multiple objective functions, physical properties of tablets, to meet the pharmaceutical criteria simultaneously. Performance measurements were used to compare the influence of the selection of initial training sets, by controlling data size and variation, acquisition functions, and schedules of hyperparameter tuning. Additionally, we investigated performance improvements obtained using Bayesian optimization techniques as opposed to random search strategy.
Bayesian optimization efficiently reduces the number of experiments to obtain the optimal formulation and process parameters from about 25 experiments with DoE to 10 experiments. Repeated hyperparameter tuning during the Bayesian optimization process stabilizes variations in performance among different optimization conditions, thus improving average performance.
We demonstrated the elimination of unnecessary experiments using Bayesian optimization. Simulations of different conditions depicted their dependencies, which will be useful in many real-world applications. Bayesian optimization is expected to reduce the reliance on individual skills and experiences, increasing the efficiency and efficacy of optimization tasks, expediting formulation and manufacturing research in pharmaceutical development.