Publications by authors named "Robert Voyer"

The recent COVID-19 pandemic revealed an urgent need to develop robust cell culture platforms which can react rapidly to respond to this kind of global health issue. Chinese hamster ovary (CHO) stable pools can be a vital alternative to quickly provide gram amounts of recombinant proteins required for early-phase clinical assays. In this study, we analyze early process development data of recombinant trimeric spike protein Cumate-inducible manufacturing platform utilizing CHO stable pool as a preferred production host across three different stirred-tank bioreactor scales (0.

View Article and Find Full Text PDF

Protein expression from stably transfected Chinese hamster ovary (CHO) clones is an established but time-consuming method for manufacturing therapeutic recombinant proteins. The use of faster, alternative approaches, such as non-clonal stable pools, has been restricted due to lower productivity and longstanding regulatory guidelines. Recently, the performance of stable pools has improved dramatically, making them a viable option for quickly producing drug substance for GLP-toxicology and early-phase clinical trials in scenarios such as pandemics that demand rapid production timelines.

View Article and Find Full Text PDF

The growing interest in the use of lentiviral vectors (LVs) for various applications has created a strong demand for large quantities of vectors. To meet the increased demand, we developed a high cell density culture process for production of LV using stable producer clones generated from HEK293 cells, and improved volumetric LV productivity by up to fivefold, reaching a high titer of 8.2 × 10 TU/mL.

View Article and Find Full Text PDF

REOLYSIN (pelareorep) is a proprietary isolate of the reovirus T3D (Type 3 Dearing) strain which is currently being tested in clinical trials as an anticancer therapeutic agent. Reovirus genomes are composed of ten segments of double-stranded ribonucleic acid (RNA) characterized by genome size: large (L1, L2, and L3), medium (M1, M2, and M3), and small (S1, S2, S3, and S4). The objective of this work was to evaluate the homogeneity and genetic stability of REOLYSIN.

View Article and Find Full Text PDF

Adenovirus production is currently operated at low cell density because infection at high cell densities still results in reduced cell-specific productivity. To better understand nutrient limitation and inhibitory metabolites causing the reduction of specific yields at high cell densities, adenovirus production in HEK 293 cultures using NSFM 13 and CD 293 media were evaluated. For cultures using NSFM 13 medium, the cell-specific productivity decreased from 3,400 to 150 vp/cell (or 96% reduction) when the cell density at infection was increased from 1 to 3 x 10(6) cells/mL.

View Article and Find Full Text PDF

Reolysin, a human reovirus type 3, is being evaluated in the clinic as an oncolytic therapy for various types of cancer. To facilitate the optimization and scale-up of the current process, a high performance liquid chromatography (HPLC) method has been developed that is rapid, specific and reliable for the quantification of reovirus type 3 particles. Using an anion-exchange column, the intact virus eluted from the contaminants in 9.

View Article and Find Full Text PDF

An anion exchange high-performance liquid chromatography (HPLC) method for the quantification of human Reovirus type 3 particles was validated according to the performance criteria of precision, specificity, linearity of calibration and working range, limits of detection and quantification, accuracy and recovery. Samples taken at various stages of Reovirus purification were used for the validation of the method. The method was specific for Reovirus which eluted around 9.

View Article and Find Full Text PDF