Experience with the Vero cell line

Area of Science:

• Vaccinology and Cell Line Technology
• Microbiology and Virology
• Biopharmaceutical Manufacturing

Background:

• The Vero cell line has been a cornerstone for vaccine production since 1982.
• Pasteur Mérieux Serums & Vaccins (PMsv) has utilized Vero cells for inactivated polio vaccine (IPV), oral polio vaccine (OPV), and rabies vaccine manufacturing.
• Cell bank management and rigorous safety testing are critical for vaccine production.

Purpose of the Study:

• To detail the safety validation processes for the Vero cell line used in vaccine production.
• To confirm the absence of adventitious agents, including specific simian viruses, in the Vero cell line.
• To provide evidence of the long-term safety and efficacy of vaccines produced using the Vero cell line.

Main Methods:

• Vero cell line management through a Cell Bank system up to the 142nd passage.
• Routine safety validation at the Working Cell Bank (WCB) level adhering to WHO and European Pharmacopoeia standards.
• Specific testing for bacteria, fungi, mycoplasma, viruses, including simian viruses (SV40, SIV, Retro-D, simian CMV).

Main Results:

• All safety tests, including those for bacteria, fungi, mycoplasma, and specific simian viruses, yielded negative results.
• Vero cells at low passage levels were confirmed to be non-tumorigenic.
• Extensive pharmacovigilance data from over 100 million doses of IPV, 20 million doses of rabies vaccine, and over 1 billion doses of OPV support the safety profile.

Conclusions:

• The Vero cell line, when managed under stringent controls and tested rigorously, provides a safe substrate for vaccine production.
• The validated safety of the Vero cell line, combined with effective downstream purification, ensures the safety of manufactured IPV, OPV, and rabies vaccines.
• Long-term pharmacovigilance confirms the excellent safety record of vaccines produced using this cell line, supporting its continued use in public health.