Study of Intradermal Administration of PCEC Rabies Vaccine

Approximately 16,000-39,000 persons come in contact with potentially rabid animals and receive rabies postexposure prophylaxis (PEP) each year in the US. To appropriately manage potential human exposures to rabies, the risk for infection must be accurately assessed. Administration of rabies PEP is a medical urgency, not a medical emergency, but decisions must not be delayed. Prophylaxis is occasionally complicated by adverse reactions, but these reactions are rarely severe. Current data on the safety and efficacy of active and passive rabies vaccination were derived from both human and animal studies. Timely and appropriate human pre-exposure prophylaxis (Pre-EP) and PEP will prevent human rabies. Currently in the US, the approved dosage and administration for PEP in previously unvaccinated persons consists of the administration of vaccine (HDCV or PCECV) and HRIG. Vaccine is administered IM on days 0, 3, 7, 21, and 28 (deltoid area). The approved dosage and administration for pre-exposure prophylaxis (Pre-EP) consists of three 1.0-mL injections of vaccine (HDCV or PCECV) administered IM (deltoid area), one injection per day on days 0, 7, and 21 or 28). Intradermal (ID) route of administration of rabies vaccination is used in certain countries both for PEP and Pre-EP, and approved by WHO for modern potent cell culture vaccines. Recent studies outside the USA found the use of PCEC rabies vaccine by ID administration immunogenic and safe. The primary goals of this study are to obtain additional safety and immunogenicity data on ID administration of 0.1 mL doses of the inactivated PCEC rabies virus vaccine in adults. Given the need to provide alternative routes of administration to the current approved intramuscular route in order to protect a larger number of people facing potential vaccine shortages. The data yielded by this clinical trial will provide evidence to support alternative route of administration and dose of PCECV in the US.