(117a) Continuous Manufacturing of Beta-Lactam Antibiotics By Enzymatic Synthesis and Crystallization: A Pilot Plant Study
- Conference: AIChE Annual Meeting
- Year: 2021
- Proceeding: 2021 Annual Meeting
- Group: Pharmaceutical Discovery, Development and Manufacturing Forum
- Time: Monday, November 8, 2021 - 12:30pm-12:54pm
In this contribution, we first review our efforts on building a mathematical model for this process and extensive simulations (1) to guide the process development for the construction of a pilot plant producing > 1 g/h of amoxicillin trihydrate and cephalexin monohydrate crystals, and (2) to identify the optimum process operating point (Fig. 1b) [2,4-5]. Our analysis points to a delicate trade-off between several process parameters such as pH, enzyme concentration, and residence time leading to a non-trivial optimization problem with several constraints dictated by critical quality attributes of the final product such as solid-phase purity. We have successfully illustrated the continuous production of cephalexin monohydrate at > 99% purity, with a productivity of 1-4 g/h for over 20 h of continuous operation. Putting a strong emphasis on the quality attributes of the product, we will briefly discuss the development of our process from the quality by design viewpoint, and will present the results of our risk assessment studies to identify the critical process parameters.
Fig.1. Main reactions in the enzymatic synthesis using Pen. G Acylase (PGA); enzyme catalyzes the synthesis of the API from an activated acyl donor (e.g., PGME) and a nucleophile containing the beta-lactam core (e.g., 7-ADCA), in addition to hydrolysis of the acyl donor and the API (a). Process simulations for identification of optimum operating point for cephalexin production (b). Example of data acquired during pilot plant operation (c). Example of online and offline product characterization (d).
 Wegman, Margreth A., Michiel HA Janssen, Fred van Rantwijk, and Roger A. Sheldon. "Towards biocatalytic synthesis of Î²âlactam antibiotics." Advanced Synthesis & Catalysis 343, no. 6â7 (2001): 559-576.
 McDonald, Matthew A., Andreas S. Bommarius, and Ronald W. Rousseau. "Enzymatic reactive crystallization for improving ampicillin synthesis." Chemical Engineering Science 165 (2017): 81-88.
 Acevedo, David, Xiaochuan Yang, Adil Mohammad, Naresh Pavurala, Wei-Lee Wu, Thomas F. OâConnor, Zoltan K. Nagy, and Celia N. Cruz. "Raman spectroscopy for monitoring the continuous crystallization of carbamazepine." Organic Process Research & Development 22, no. 2 (2018): 156-165.
 Salami, Hossein, Colton E. Lagerman, Patrick R. Harris, Matthew A. McDonald, Andreas S. Bommarius, Ronald W. Rousseau, and Martha A. Grover. "Model development for enzymatic reactive crystallization of Î²-lactam antibiotics: a reactionâdiffusion-crystallization approach." Reaction Chemistry & Engineering 5, no. 11 (2020): 2064-2080.
 McDonald, Matthew A., Andreas S. Bommarius, Ronald W. Rousseau, and Martha A. Grover. "Continuous reactive crystallization of Î²-lactam antibiotics catalyzed by penicillin G acylase. Part I: Model development." Computers & Chemical Engineering 123 (2019): 331-343.