Optimizing manufacturing of a complex bispecific antibody

An emerging biotech company approached Enzene Biosciences with a novel fully human albumin binding (FHAB) protein. This FHAB- interleukin-12 suffered from low titers (16-18 mg/L per fed-batch run), poor viability after 10 days of growth, proteolytic clipping, limited operational pH range, and host cell protein (HCP) problems due to low productivity.

The lack of an efficient capture step also contributed to the low yields. These hurdles were preventing the candidate from reaching Phase I clinical supply.

In partnership with Enzene Biosciences, a new approach was taken to overcome development issues and optimize the production process for clinical applications. A unique solution was leveraged to transform the process from a fed- batch approach to the use of Enzene’s continuous perfusion in upstream manufacturing. Shifting to a continuous manufacturing process aimed to improve cell density and increase harvest productivity to reach commercial viability. Each process step was connected for a seamless transition, increasing production efficiency.

When developing the new perfusion process, the three key factors explored and optimized included media and feed, cell-specific perfusion rate (CSPR), and alternating tangential flow filtration (ATF) exchange rate (perfusion rate). Downstream processing resins were also screened to optimize the capture step, maximizing product recovery while maintaining purity. Implementing the new perfusion process helped to overcome the productivity bottleneck that could hinder the transition to clinical stages.

Using an agile approach to problem-solving, innovative design thinking, and continuous experimentation, an optimized, commercially viable manufacturing process that met the current good manufacturing process (cGMP) requirements was implemented within six months.

As a result of transitioning to continuous manufacturing, an 8x cumulative increase in productivity and a high titer of over 80% were observed , yielding 500,000 doses of the drug product per 20 L perfusion. In addition, the minimal product exposure to proteolytic enzymes when processed in a continuous process promoted stability to ensure that the product yielded remained active. In summary, the final perfusion process provided consistency and scalability from bench to commercial.

Following the success of this project, a long-term relationship was established with the emerging biotech company. The expansion of the statement of work to include several other projects has further strengthened the collaboration between Enzene Biosciences and the client.