[Investigation of in vitro and in vivo efficacy of a novel alcohol based hand rub, MR06B7].

Alcohol based hand rubs have been used for hand hygiene in health-care settings. Compared with hand scrubbing, using suitable alcohol based hand rub provides several advantages like usability in a ward with no tap, requiring less time and mildly-irritating. Alcohol provides immediate activity, but poor virucidal activity against certain viruses including norovirus. It is important to develop further improved alcohol based hand rubs which have characteristics of sufficient effectiveness, skin-safe and extended spectrum to non-enveloped viruses for infection control. In the study, in vitro microbicidal evaluations and in vivo efficacy evaluation study were investigated to clarify the characteristics of a novel hand antiseptic MR06B7 composed of additives with synergetic activities. MR06B7 showed bactericidal activity of more than 5 Log(10) reduction within 15 sec against 20 challenged strains. MR06B7 also demonstrated potent fungicidal activities at exposure time of 30 sec (more than 4 Log(10) reduction). Against all test viruses including non-enveloped viruses (adenovirus, feline calicivirus, murine norovirus and poliovirus), MR06B7 had excellent virucidal activity to reduce the titer of viability to the limit of detection within 30 sec exposure (more than 4 Log(10) reduction), whereas 83%(v/v) ethanol indicated the inadequate effectiveness. On the clinical study conducted in accordance with standard method for Healthcare Personnel Handwash of American Society for Testing and Materials, MR06B7 showed excellent immediate antimicrobial activity. The result surpassed the critical indices set forth in the FDA's Tentative Final Monograph. These findings suggest MR06B7 which satisfies most requirements of efficacy qualifications including potent virucidal activity against non-enveloped viruses may contribute to accomplish advanced infection control in clinical practice.