Efficacy and safety of a non-adjuvanted Bordetella bronchiseptica extract vaccine with recombinant pertactin administered subcutaneously to dogs.

BACKGROUND

This study aimed to assess the efficacy and safety of the Vanguard® Recombishield™ Injectable Bordetella, a non-adjuvanted Bb extract vaccine containing recombinant pertactin, in dogs using controlled challenge and field studies.

METHODS

In the challenge study, 40 eight-week-old beagle puppies were randomly assigned to two groups to receive two subcutaneous doses of either placebo or vaccine on Days 0 and 21. On Day 42, all dogs were challenged with aerosolized virulent Bb. Clinical signs were monitored regularly, with two consecutive days of coughing as the primary efficacy variable. Nasal swabs for bacterial isolation were collected on Days -10, 0, every other day from Day 42 to 70. Antibody titers were measured on Days -10, 0, 21, 42 and 70. A separate field study assessed vaccine safety in 624 client-owned dogs, each of which received two subcutaneous doses 3-4 weeks apart. Veterinarians monitored immediate post-vaccination reactions for 10-20 min, while owners reported delayed adverse health events from the first dose through 10 days after the second dose.

RESULTS

Vaccinated puppies exhibited substantially reduced clinical signs following challenge. Only 1 out of 20 (5.0%) vaccinated puppies experienced coughing over two consecutive days, compared to 16 out of 20 (80.0%) in the control group (P = 0.0014). The duration of coughing was significantly shorter in vaccinated puppies (3.2 days) than in controls (16.0 days). Additionally, vaccinated puppies exhibited reduced bacterial shedding and developed significantly higher post-challenge antibody titers (p < 0.0001). In the field study, adverse events were rare (0.56%), mild, and transient, with no serious reactions reported among the 1242 administered doses.

CONCLUSIONS

Vanguard® Recombishield™ Injectable Bordetella significantly reduced coughing and bacterial shedding, while eliciting a strong immune response. Vaccine was well tolerated in a diverse canine population, supporting its use as a safe and effective preventive measure against Bb infection.