Boehringer’s PUREVAX RCPCh FeLV (FeLV recombinant canarypox virus (vCP97)) is a vaccine used to protect cats from feline viral rhinotracheitis, calicivirus, panleukopenia, Chlamydophila felis, and feline leukemia virus (FeLV). Recombinant technology uses a modified canarypox virus to deliver the antigens, which are specific parts of the disease-causing organisms, without causing the disease itself.