Scale-up issues during sterile filtration of glycoconjugate vaccines.

Several recent studies have provided important insights into the factors controlling the sterile filtration of glycoconjugate vaccines; however, this work has been limited to small-scale disk filters with very uniform flow distribution. The objective of this study was to examine the scale-up of the sterile filtration step using a glycoconjugate drug substance made from a single polysaccharide serotype. Experimental data were obtained during constant flux filtration through 0.

Evaluation of single-use tangential flow filtration technology for purification of activated polysaccharides used in conjugate vaccine manufacturing.

Over the past decade, single-use tangential flow filtration (TFF) technologies have emerged to reduce system preparation time, promote fast and flexible product change over, and ultimately shorten process development and manufacturing time/cost. In this study, the performance of a recently developed Pellicon® single-use TFF capsule was compared against traditional Pellicon® cassettes by assessing TFF process performance (such as flux, residuals clearance, and yield) and post-purification product attributes (such as concentration and mass-weighted average molecular weight). Good scaling was shown by comparing process performance and product attributes across different scales and formats.

Prefiltration enhances performance of sterile filtration for glycoconjugate vaccines.

Recent studies have reported very low capacity during sterile filtration of glycoconjugate vaccines due to rapid fouling of the sterile filter. The objective of this study was to explore the potential for significantly increasing the capacity of the sterile filter through the use of an appropriate prefilter. Data were obtained using prefilters with different pore size and chemistry, with the sterile filtration performed at constant filtrate flux using 0.

Fouling Behavior during Sterile Filtration of Different Glycoconjugate Serotypes Used in Conjugate Vaccines.

Purpose: Sterile filtration can be a particular challenge when processing very large glycoconjugate vaccines. The objective of this study was to examine the sterile filtration performance of a series of glycoconjugate vaccines produced by coupling different polysaccharide serotypes to an immunogenic protein.

Methods: Sterile filtration was performed at constant filtrate flux using 0.

Purification of a conjugated polysaccharide vaccine using tangential flow diafiltration.

Conjugated vaccines prepared from the capsular polysaccharide of Streptococcus pneumoniae can provide immunization against invasive pneumococcal disease, meningitis, and otitis media. One of the critical steps in the production of these vaccines is the removal of free (unreacted) polysaccharides from the protein-polysaccharide conjugate. Experimental studies were performed to evaluate the effects of membrane pore size, filtrate flux, and solution conditions on the transmission of both the conjugate and free polysaccharide through different ultrafiltration membranes.

Effects of Plasma Proteins on the Transport and Surface Characteristics of Polysulfone/Polyethersulfone and Asymmetric Cellulose Triacetate High Flux Dialyzers.

Blood-membrane interactions can have a large impact on the performance of hemodialysis membranes, particularly for high flux membranes in which the membrane itself provides very low resistance to solute transport. The objective of this study was to examine the effects of exposure to serum on the solute clearance and convective sieving characteristics of high flux polysulfone (Optiflux F250NR), polyethersulfone (ELISIO-25H), and asymmetric cellulose triacetate (SOLACEA-25H) hemodialyzers using both vitamin B and a range of polydisperse dextrans. Zeta potential measurements were used to obtain additional insights into the changes in membrane surface properties.

Transport Characteristics of Asymmetric Cellulose Triacetate Hemodialysis Membranes.

Aims: The objective of this study was to compare the transport characteristics of highly asymmetric cellulose triacetate (ATA™) membranes with that of both symmetric cellulose triacetate and asymmetric polysulfone membranes.

Methods: Data were obtained for solute clearance and sieving coefficients of vitamin B12 and a range of polydisperse dextrans using ATA™ SOLACEA-25H and Optiflux F250NR polysulfone dialyzers. Results for these, and the CT190 symmetric cellulose triacetate dialyzer, were analyzed using available membrane transport models.