Challenges for Viral Vector Production for Translational Gene Therapy

 

In academic and/or translational laboratories, usually small amounts of virus are required. Most upstream vector production at this stage is adherent and carried out in small flasks, and possibly scaled up slightly to cell stacks. Vector production also requires transient transfection of the adherent cell lines with plasmids, which means that the optimization of clones that is generally carried out during process development of mAbs is not applicable for these technologies. There can be considerable challenges with scaling up adherent cultures.

Once the cell culture is complete, the virus must then go through recovery, purification and formulation. In many cases, the product is contained within the cell, so cell lysis needs to take place. Usually, precipitation and ultracentrifugation techniques are used to recover and purify the virus, but these are not scalable processes. Formulation then requires getting the vector into high concentrations, and this can cause both clumping and stability issues.


All in all, there are many issues with lab-scale generation of viral vectors, and completely new processes must be used when scaling these up. 

 

 

 

The Benefits of Using Scalable Technologies for Viral Vector Manufacturing During the Early Stages of Development Work

 

Usually, the manufacturing processes during early-stage development of the gene therapy are based on non-commercially viable production platforms. Transferring and optimizing the process to a scalable manufacturing platform is therefore a necessity.

To achieve manufacturing platform advancement, the product needs to be very well-characterized during development so that investigators can generate data sets which demonstrate comparability between products used in clinical studies, and those generated with the final manufacturing process.

 

Our downstream process technologies are available in bench-scale format for early-stage bioprocess development.

 

Crude Harvest Volume (L)

<  0.8 L

Clarification Depth Filter

Supracap™ 50 Capsule 

AEX Membrane Chromatography

Mustang® XT Acrodisc® Unit

Ultrafiltration/ Diafiltration (UF/DF)

Cadence® SUTFF Module

Sterile Filtration (0.2 µm)

Acrodisc® filters

These process-development scale consumables are designed to scale directly to larger configurations to meet the demands for cGMP clinical and manufacturing production.

Our Scientific and Laboratory Services group is the Right Partner for Your Gene Therapy Development

 

Scientific and Laboratory Services (SLS) is our customer-focused technical support organization. It comprises scientific and technical staff working closely on the bench with customers and offering support and consulting for (early phase) drug development projects.

 

 

Learning

Learn from experts and discover how using scalable manufacturing tools can accelerate your gene therapy development

Sterile Filtration of Adeno-Associated Viruses: Part 1


The first in a short series of practical guidance notes for the selection and testing of sterilizing-grade filtration used in the production of viral vectors.

 

This video focuses on the importance of filtration and the filter formats available to scale from bench-scale testing to large scale GMP production.

Sterile Filtration of Adeno-Associated Viruses: Part 2

 

The second in a short series of practical guidance notes for the selection and testing of sterilizing-grade filtration used in the production of viral vectors. 

 

This video focuses on how to set-up a bench-scale filterability study of AAV using reduced product availability.

Sterile Filtration of Adeno-Associated Viruses: Part 3

 

The third in a short series of practical guidance notes for the selection and testing of sterilizing-grade filtration used in the production of viral vectors. 

 

This video focuses on how to set up a bench-scale filterability study of AAV using a pump.

Further Reading

Read more
Adeno-associated viruses (AAV) are small viruses that can infect humans and primates and can be found everywhere. In this blog we review why they led themselves to gene therapy.
I have been fortunate to work alongside many customers on a diverse range different processes, each one comes with its own unique challenges, perhaps none more so than viral vectors. In this blog we take a look at different scale-up strategies.
Clarification removes cells and cell debris, lowering the turbidity to make the feedstream compatible with chromatography. This prepares the way for chromatographic separation, but as AAV concentrations out of the bioreactor can be relatively modest compared to resin capacity.
What is the future of gene therapy? Mark Schofield looks at the story to date and future, in this blog post.