[Antigenicity studies of prulifloxacin (NM441)]

Antigenicity of prulifloxacin, a new antibacterial agent, and that of its active metabolite (NM394) were investigated using guinea pigs and mice in this study. In the study with guinea pigs, the animals were immunized with prulifloxacin by oral administration, the predetermined clinical route, and with prulifloxacin alone or emulsified with Freund's complete adjuvant (FCA) by s.c. When active systemic anaphylaxis (ASA) test and passive cutaneous anaphylaxis (PCA) test of these animals were conducted by eliciting with NM394 alone or protein conjugate (NM394-GPSA) of NM394 and guinea pig serum albumin (GPSA), no ASA and PCA reactions were observed. When guinea pigs were immunized subcutaneously with protein conjugate (NM394-BSA) of NM394 and bovine serum albumin (BSA) together with FCA, ASA and PCA reactions were positive by eliciting with NM394-GPSA or NM394-BSA, but were negative by eliciting with NM394 alone. In the study with mice, the animals were immunized orally with prulifloxacin and intraperitoneally with prulifloxacin alone or suspended with aluminum hydroxide gel (alum). When rat PCA test of sera from these mice was conducted by eliciting with NM394 or NM394-GPSA, no positive PCA reaction was observed. When mice were immunized intraperiotneally with NM394-BSA together with alum, PCA reactions were positive by eliciting with NM394-GPSA or NM394-BSA, but were negative by eliciting with NM394 alone. These results show that prulifloxacin has no immunogenicity to guinea pigs and mice, and NM394 as its active form has no eliciting potential to anti-NM394-BSA antibody.