Design and techno-economic assessment of an industrial-scale polyvalent clostridial vaccine production process

This study presents a structured process design for a polyvalent veterinary clostridial vaccine along with a comprehensive techno-economic analysis. Four scenarios were evaluated by examining the primary factors: (i) cultivation equipment (stainless-steel (SS) versus single-use bioreactor (SUB)), (ii) options for the inactivation and formulation processes (1500-L and 250-L SS vessels, or 750-L SUB bags), (iii) in process quality control strategies (conventional 14-day sterility testing versus rapid 1-day testing), and (iv) a closed-system design for formulation and filling. The base scenario (characterized by high demand for 250-L SS equipment, long sterility assays, and an open system design) indicated a production capacity of 32 million doses with unfavorable economics (ROI -65%, gross margin -47%, and NPV -5.0 million USD over 15-year lifetime). Introduction of rapid sterility testing across three alternative scenarios yielded identical process durations and an annual output of 51.2 million doses, but with distinct capital and operating cost profiles. Notably, the use of single-use components reduced capital costs and water consumption, but totally resulted in negative economic indicators. Another scenario (scenario 3), featuring fewer SS equipment and a closed-system design, yielded a positive NPV (∼3.66 million USD), a payback of 1.4 years, a gross margin of 35%, and ROI of 23%. Sensitivity analysis revealed that NPV is most influenced by the product selling price, followed by labor, material, and utility costs. With a ±25% variation in various factors, only the optimized scenario (scenario 3) maintained profitability. Collectively, scenario 3 emerged as the most viable option for sustained industrial clostridial vaccine production.