Retroviral elements are endogenously expressed during the cultivation of certain mammalian cells (ex. Chinese Hamster Ovary) used for biopharmaceutical production. After expression, these products form replication-deficient retrovirus like particles (RVLP). Although non-infectious, regulatory agencies require biopharmaceutical companies that utilize these cell lines to demonstrate that their purification process can remove retrovirus. This is commonly accomplished through Xenotropic Murine Leukemia Virus (XMulV) spiking studies which require BSL-2 laboratories and experienced personnel. MockV Solutions is developing an RVLP Kit which will contain a stock solution of highly concentrated and purified RVLP for direct BSL- compatable spiking studies. These kits will enable scientists to accurately and economically determine RVLP clearance throughout process development, prior to expensive validation studies. We expect the RVLP Kit to be available in mid-2018.