Environmental Health and Safety Offers a Biosafety Risk Assessment for a Theoretical Model of a Gene Therapy Process Transfer from Research and Development to Large-Scale Manufacturing.

Introduction: This article provides a strategy by which a manufacturing process with a Biosafety Level 2 (BL2) designation can be downgraded to Biosafety Level 1 (BL1). The principles of the downgrading process are based on the robust contamination controls in clinical and commercial manufacturing, which typically are not part of Research and Development processes. These strict requirements along with the application of current Good Manufacturing Practice (cGMP) principles provide a framework by which processes can be suitably managed and controlled to mitigate biohazard risk, specifically for cell lines that may be contaminated with human pathogenic viral agents. Purpose: We demonstrate how a risk assessment guide was used to define the risk profile of a theoretical process with a human cell line intended for clinical/commercial application. Based on the risk assessment, key BL2 elements were identified as suitable for downgrading, including facility containment controls, emergency spill response plans, and storage and shipping requirements. For various reasons, some aspects of the systems were deemed unsuitable for downgrading due to the severity of the control risk and, therefore, remained at BL2. Summary and Conclusions: We have used an established risk assessment guide to show how cGMP compliments and augments biosafety containment. We provide justification for downgrading from BL2 to BL1 for clinical and commercial cell and gene therapy manufacturing with human cell lines.

Heparin Isomeric Oligosaccharide Separation Using Volatile Salt Strong Anion Exchange Chromatography.

The complexity of heparin and heparan sulfate saccharides makes their purification, including many isomeric structures, very challenging and is a bottleneck for structure-activity studies. High-resolution separations have been achieved by strong anion exchange (SAX) chromatography on Propac PA1 and cetyltrimethylammonium (CTA)-C18 silica columns; however, these entail subsequent desalting methodologies and consequent sample losses and are incompatible with orthogonal chromatography methodologies and, in particular, mass spectrometry. Here, we present the CTA-SAX purification of heparin oligosaccharides using volatile salt (VS) buffer. In VSCTA-SAX, the use of ammonium bicarbonate buffer for elution improves resolution through both weaker dissociation and conformational coordination of the ammonium across the sulfate groups. Using ion mobility mass spectrometry, we demonstrate that isomeric structures have different structural conformations, which makes chromatographic separation achievable. Resolution of such structures is improved compared to standard SAX methods, and in addition, VSCTA-SAX provides an orthogonal method to isolate saccharides with higher purity. Because ammonium bicarbonate is used, the samples can be evaporated rather than desalted, preventing substantial sample loss and allowing more effective subsequent analysis by electrospray mass spectrometry. We conclude that VSCTA-SAX is a powerful new tool that helps address the difficult challenge of heparin/heparan sulfate saccharide separation and will enhance structure-activity studies.