Evolution of a Green and Sustainable Manufacturing Process for Belzutifan: Part 4─Applications of Process Analytical Technology in Heterogeneous Biocatalytic Hydroxylation

Abstract

Belzutifan has been approved recently by the U.S. Food and Drug Administration (FDA) for treating patients with certain types of Von Hippel-Lindau (VHL) disease-associated tumors. Although a commercial synthetic process has been established to make belzutifan, a further optimized process with fewer steps, improved cost-effectiveness, and a smaller environmental footprint is always in demand. In the new commercial synthetic route, a single-step biocatalytic hydroxylation reaction was used to replace the five chemical steps required in the previous route. In developing this new biocatalytic reaction, multiple process analytical technologies (PATs), such as Fourier transform infrared spectroscopy (FTIR), in situ imaging, dissolved oxygen monitoring, etc., were used to track important reaction parameters under complex reaction conditions (e.g., multiphases and dense slurry). With quantitative modeling, the product concentration and yield can be tracked in real time based on FTIR. This is particularly important for dense slurry reactions, for which offline sampling becomes challenging due to the sample inhomogeneity. In-depth mechanistic insights were also obtained using PATs revealing reaction kinetics controlled by different mass transfer limited processes, as well as the unique role of 1-octanol. These PAT-enabled capabilities for reaction tracking and understanding facilitated process development from the laboratory to the pilot scale and ensured a robust process for the hydroxylation reaction.

Evolution of a Green and Sustainable Manufacturing Process for Belzutifan: Part 3─Development of a Scalable Enzymatic Oxidation Process

“…However, measurement of the indanone 1 concentration over time for different reaction mixtures (Figure ) indicated that the presence of 1-octanol slowed the initial dissolution of indanone 1 and did not change the saturation concentration. Further imaging studies under reaction conditions suggested that the interaction between indanone 1 and 1-octanol prevents the aggregation of indanone 1 . Therefore, 1-octanol helps maintain a consistent indanone 1 dissolution rate throughout the course of the reaction, despite slowing the dissolution rate at the beginning of the reaction.…”

“…However, reactions in the presence of 1-octanol generated a well-behaved slurry by physical observation. In situ imaging of indanone 1 in the presence of 1-octanol showed that indanone 1 particles mostly distributed at the surface of 1-octanol droplets, suggesting an interaction between 1-octanol and indanone 1 likely due to hydrophobic forces . Thus, it was initially hypothesized that 1-octanol may improve conversion through this interaction by improving the dissolution rate or increasing the saturation concentration of indanone 1 in the aqueous layer.…”

Accelerating reaction optimization through data-rich experimentation and machine-assisted process development

“…Automation and data-rich experimentation (DRE) have revolutionized process development by offering enhanced capabilities at the lab benchtop. 1 The integration of process analytical tools, such as on-line HPLC 2,3 and in situ spectroscopy, 4–7 increases the data density in each experiment, providing information on both the reaction kinetics and the overall reaction performance. Enhancements to throughput can be achieved through the utilization of parallel reactor technology, integrated with automated sampling strategies, allowing for collection of comprehensive reaction profiles.…”