Poliovirus type 2 (inactivated)

Table of contents

• What is poliovirus type 2 (inactivated)?
• How does poliovirus type 2 (inactivated) work?
• Which conditions is poliovirus type 2 (inactivated) used or studied for?
• How is poliovirus type 2 (inactivated) given?
• What do the clinical trials show?

What is poliovirus type 2 (inactivated)?

Poliovirus type 2 (inactivated) is one of three inactivated poliovirus strains used in vaccines against poliomyelitis, a viral infection that can cause permanent paralysis.

How does poliovirus type 2 (inactivated) work?

Inactivated poliovirus vaccines work by presenting the immune system with killed poliovirus particles that cannot cause disease but still trigger a protective immune response. The World Health Organization (WHO) recommendations on inactivated poliomyelitis vaccines describe how the vaccine induces neutralising antibodies against the three poliovirus serotypes, including type 2.^[2] This antibody response prepares the body to fight off a future poliovirus infection before it can reach the nervous system and cause paralysis.

Which conditions is poliovirus type 2 (inactivated) used or studied for?

• Poliomyelitis — the vaccine is authorised for active immunisation against poliomyelitis caused by poliovirus types 1, 2, and 3 in infants, children, and adults.^[3]
• Pertussis (whooping cough) — in one completed trial, the combination vaccine containing poliovirus type 2 (inactivated) served as the comparator to investigate whether an acellular pertussis booster reduces Bordetella pertussis colonisation in healthy adults.^[1]

How is poliovirus type 2 (inactivated) given?

Poliovirus type 2 (inactivated) is given as part of a suspension for injection. In the clinical trial, REVAXIS was administered as a 0.5 ml injection.^[1] The product information for the standalone IPOL vaccine from the FDA describes administration by injection as well.^[3]

What do the clinical trials show?

One completed interventional trial used a vaccine containing poliovirus type 2 (inactivated). The study, designated 2023-508416-35-00, was a Phase 3 randomised vaccination study in 99 healthy adults.^[1] Its purpose was to investigate whether booster vaccination with a tetanus, diphtheria, acellular pertussis, and inactivated polio vaccine (Tdap-IPV) reduces colonisation with Bordetella pertussis after intranasal challenge, compared to the tetanus, diphtheria, and inactivated polio vaccine (Td-IPV) control group.^[1] In this trial, REVAXIS — which contains poliovirus type 2 (inactivated) — was the comparator, not the vaccine under investigation.^[1]

The primary outcome was the Bordetella pertussis colonisation rate in the Tdap-IPV and Td-IPV vaccination groups, defined as any positive Bordetella pertussis culture from nasal wash samples taken at any time point between Day 3 and Day 28 after challenge.^[1]