title: At-line process analytical technology (PAT) for more efficient scale up of biopharmaceutical microfiltration unit operations.
abstract: Tangential flow microfiltration (MF) is a cost-effective and robust bioprocess separation technique, but successful full scale implementation is hindered by the empirical, trial-and-error nature of scale-up. We present an integrated approach leveraging at-line process analytical technology (PAT) and mass balance based modeling to de-risk MF scale-up. Chromatography-based PAT was employed to improve the consistency of an MF step that had been a bottleneck in the process used to manufacture a therapeutic protein. A 10-min reverse phase ultra high performance liquid chromatography (RP-UPLC) assay was developed to provide at-line monitoring of protein concentration. The method was successfully validated and method performance was comparable to previously validated methods. The PAT tool revealed areas of divergence from a mass balance-based model, highlighting specific opportunities for process improvement. Adjustment of appropriate process controls led to improved operability and significantly increased yield, providing a successful example of PAT deployment in the downstream purification of a therapeutic protein. The general approach presented here should be broadly applicable to reduce risk during scale-up of filtration processes and should be suitable for feed-forward and feed-back process control.
authors.affiliation: Merck & Co, Inc, Merck Manufacturing Div., Elkton, VA, 22827.
authors.forename: Douglas S
authors.initials: DS
authors.lastname: Watson
authors.affiliation: Merck & Co, Inc, Merck Manufacturing Div., Elkton, VA, 22827.
authors.forename: Kristi R
authors.initials: KR
authors.lastname: Kerchner
authors.affiliation: Merck & Co, Inc, Merck Manufacturing Div., Elkton, VA, 22827.
authors.forename: Sean S
authors.initials: SS
authors.lastname: Gant
authors.affiliation: Merck & Co, Inc, Merck Manufacturing Div., Elkton, VA, 22827.
authors.forename: Joseph W
authors.initials: JW
authors.lastname: Pedersen
authors.affiliation: Merck & Co, Inc, Merck Manufacturing Div., Elkton, VA, 22827.
authors.forename: James B
authors.initials: JB
authors.lastname: Hamburger
authors.affiliation: Merck & Co, Inc, Merck Manufacturing Div., Elkton, VA, 22827.
authors.forename: Allison D
authors.initials: AD
authors.lastname: Ortigosa
authors.affiliation: Merck & Co, Inc, Merck Manufacturing Div., Elkton, VA, 22827.
authors.forename: Thomas I
authors.initials: TI
authors.lastname: Potgieter
mesh_terms: D001709:Biotechnology; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005374:Filtration / Q000379:methods*; D011506:Proteins / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D011506:Proteins
keywords: bioprocess; feed-back control; feed-forward control; microfiltration; process analytical technology; quality by design