MockV Solutions Announces Collaboration Focused on Predicting Viral Clearance During AAV Bioprocess Development

Rockville, MD – October 16, 2019 MockV Solutions, Inc. (MockV or the Company), a company developing innovative products to analyze viral clearance during process development, announced today that it has signed a test and study agreement with REGENXBIO Inc. (REGENXBIO), Thermo Fisher Scientific Inc. (Thermo Fisher) and Texcell-North America, Inc. (Texcell NA) to evaluate MockV’s MVM-MVP Kit for predicting Minute Virus of Mice (MVM) clearance during adeno-associated virus (AAV) bioprocessing.

The intention of this test and study agreement is to determine if the non-infectious Mock Virus Particles (MVP) could be used as an accurate and economic indicator of MVM clearance during AAV purification process development studies, and to determine if MVM and Xenotropic Murine Leukemia Virus (XMuLV) clearance can be achieved through Thermo Fisher’s POROS® CaptureSelect™ AAVX affinity resin. Implementing affinity chromatography resins like POROS CaptureSelect AAVX enables a scalable platform approach to AAV downstream processing. However, it is unknown if model viruses such as MVM and XMuLV would separate from AAV during processing and enable viral clearance reduction claims. This collaboration will address this question through live viral clearance spiking studies (performed at Texcell NA).

The MVM-MVP Kit contains a non-infectious MVP spiking surrogate that mimics the physicochemical characteristics of MVM, a small and physiochemically resistant parvovirus used as a universal standard for assessing viral clearance during process validation studies.

“Affinity chromatography can contribute to viral reduction in the downstream processing of mAb therapeutics,” said Brandon Pence, Vice President and General Manager, Purification and Pharma Analytics at Thermo Fisher. “However, viral clearance is not well characterized in emerging therapeutic modalities like gene therapy. These studies have the potential to provide critical data and process parameter insights on the effect of affinity chromatography on viral clearance in AAV processes, as well as additional classes of viral vectors.”

In a parallel study, a non-infectious MVM surrogate will be used as a spiking agent.  This MVM-MVP is available through MockV’s MVM-MVP Kit. “The advantage of MockV’s MVM-MVP Kit is that predictive small-scale development studies can be performed in-house at a fraction of the costs of conducting a live viral clearance study,” said David Cetlin, M.S., Chief Executive Officer of MockV.  “This will enable companies like REGENXBIO to explore the impacts of process parameters such as residence time and resin load capacity on MVM clearance and reveal the edges of their process design space. We look forward to working with REGENXBIO, Thermo Fisher and Texcell N.A. as we evaluate our commercial product for use in the AAV market.”

“Currently, the downstream AAV process development space is an exciting arena to be working in,” said MockV Executive.  Novel products such as AAV affinity resins and monoliths are making their mark and a lot of questions surrounding the ability and strategy to demonstrate viral clearance are being asked.  Our MVM-MVP Kit might provide an economical and effective means to accumulate knowledge during the years leading up to a validation study. We are excited to move forward with this collaboration and to hopefully help the AAV world advance their life saving therapeutics.”


REGENXBIO is a leading clinical-stage biotechnology company seeking to improve lives through the curative potential of gene therapy. REGENXBIO’s NAV® Technology Platform, a proprietary adeno-associated virus (AAV) gene delivery platform, consists of exclusive rights to more than 100 novel AAV vectors, including AAV7, AAV8, AAV9 and AAVrh10. REGENXBIO and its third-party NAV Technology Platform Licensees are applying the NAV Technology Platform in the development of a broad pipeline of candidates in multiple therapeutic areas. For more information, visit

About Texcell North America, Inc.

Texcell-North America, Inc. is a global contract research organization based in the Maryland/Virginia biotech corridor specializing in custom cell culture, virus propagation, virus concentration, viral clearance services, and viral safety testing in support of biopharmaceutical applications submitted to the FDA and other regulatory authorities. Since 2002, our team has cultivated an ever-increasing range of experience performing viral clearance studies for a wide variety of purification steps including chromatography, filtration, and inactivation methods, as well as evaluations of column age and sanitization, or cleaning efficacy. We offer our clients a personalized and tailored approach to study design with the advantage of an extensive historical viral clearance database of over 10,000 studies performed by our global organization. Through partnerships with other Texcell facilities around the world, we have expanded our services portfolio to include cGMP cell bank production, cell bank characterization and GMP compliant animal studies. We are proud to support research that continues to improve global quality of life.

For further information regarding Texcell, please visit:

About MockV, Inc. 

MockV Solutions, Inc. (MVS) is a biotechnology company commercializing non-infectious viral-surrogate tools to a variety of industries that currently rely on expensive and logistically challenging live virus analysis. MockV is developing a novel series of analytical assay kits which will enable biopharmaceutical process development scientists to study the efficacy of manufacturing techniques intended to remove or inactive virus, a contaminant of great concern during the manufacturing of biopharmaceuticals.  These products are only approved for clinical or commercial use after their manufacturing processes demonstrate sufficient viral clearance. Currently, this is accomplished through the use of live mammalian model viruses (ex. MVM and XMuLV) in expensive and logistically challenging “spiking studies”.  The lack of economical and accurate means of analyzing viral clearance during small scale process development increases the risk of failing viral clearance regulatory requirements – jeopardizing the timely approval of potentially life-altering therapies. MockV’s first commercial product, the MVM-MVP Kit contains a non-infectious “Mock Virus Particle” (MVP) that mimics the physicochemical characteristics of live infectious MVM, as well as reagents and components to quantify MVP in solution.

For further information regarding MockV Solutions, Inc., please visit the Company’s website at