Stabilization and formulation of a recombinant Human Cytomegalovirus vector for use as a candidate HIV-1 vaccine. Issue 44 (16th October 2019)

• Record Type: Journal Article
• Authors: Kumru, Ozan S.; Saleh-Birdjandi, Soraia; Antunez, Lorena R.; Sayeed, Eddy; Robinson, David; van den Worm, Sjoerd; Diemer, Geoffrey S.; Perez, Wilma; Caposio, Patrizia; Früh, Klaus; Joshi, Sangeeta B.; Volkin, David B.
• Is Part Of: Vaccine. Volume 37:Issue 44(2019)
• Page Start: 6696
• Page End: 6706
• Publication Date: 2019-10-16
• Subjects: HIV vaccine -- Cytomegalovirus -- Formulation -- Freeze-thaw -- Stability -- Excipient; BDS Bulk Drug Substance -- BSA bovine serum albumin -- CMV cytomegalovirus -- CO2 carbon dioxide -- cP centipoise -- DAPI 4′, 6-diamidino-2-phenylindole -- DTT dithiothreitol -- dPBS Dulbecco's phosphate-buffered saline -- FBS fetal bovine serum -- FFU fluorescence focus units -- FITC fluorescein isothiocyanate -- HNS buffer 25 mM Histidine, 150 mM NaCl, 10% (w/v) sucrose, pH 6.0 -- IE-IFA intermediate-early indirect immunofluorescence assay -- Log log units are in base 10 -- MOI multiplicity of infection -- OHSU Oregon Health Sciences University -- PDL population doubling level -- PBS phosphate buffered saline, pH 7.4 -- PP polypropylene -- PVDF polyvinylidene difluoride -- TNS buffer 50 mM Tris, 150 mM NaCl, 10% (w/v) sucrose, pH 8.0 -- w/v weight/volume; Vaccines -- Periodicals; 615.372
• DOI: 10.1016/j.vaccine.2019.09.027
• Languages: English
• ISSNs: 0264-410X

Abstract

Abstract: Live attenuated viral vaccine/vector candidates are inherently unstable and infectivity titer losses can readily occur without defining appropriate formulations, storage conditions and clinical handling practices. During initial process development of a candidate vaccine against HIV-1 using a recombinant Human Cytomegalovirus vector (rHCMV-1), large vector titer losses were observed after storage at 4 °C and after undergoing freeze-thaw. Thus, the goal of this work was to develop candidate frozen liquid formulations of rHCMV-1 with improved freeze-thaw and short-term liquid stability for potential use in early clinical trials. To this end, a virus stability screening protocol was developed including use of a rapid, in vitro cell-based immunofluorescence focus assay to quantitate viral titers. A library of ∼50 pharmaceutical excipients (from various known classes of additives) were evaluated for their effect on vector stability after freeze-thaw cycling or incubation at 4 °C for several days. Certain additives including sugars and polymers (e.g., trehalose, sucrose, sorbitol, hydrolyzed gelatin, dextran 40) as well as removal of NaCl (lower ionic strength) protected rHCMV-1 against freeze-thaw mediated losses in viral titers. Optimized solution conditions (e.g., solution pH, buffers and sugar type) slowed the rate of rHCMV-1 titer losses in the liquid state at 4 °C. After evaluating various excipient combinations, three new candidate formulations were designed and rHCMV-1 stability was benchmarked against both the currently-used and a previously reported formulation. The new candidate formulations were significantly more stable in terms of reducing rHCMV-1 titer losses after 5 freeze-thaw cycles or incubation at 4 °C for 30 days. This case study highlights the utility of semi-empirical design of frozen liquid formulations of a live viral vaccine candidate, where protection against infectivity titer losses due to freeze-thaw and short-term liquid storage are sufficient to enable more rapid initiation of early clinical trials.