Novel characteristics of a 60% isopropanol hand rub formulated to meet tentative final monograph healthcare personnel handwash criteria

Abstract

BACKGROUND: A healthcare personnel handwash (HCPH) is defined in the Tentative Final Monograph for Healthcare Antiseptic Drug Products (TFM) as an antiseptic handwash that demonstrates a 2 log10 reduction of a marker organism, Serratia marcescens, after wash 1 and a 3 log10 reduction after wash 10. In addition to the rapid, broad-spectrum efficacy requirements, antiseptic handwash products should be formulated to maintain skin condition and should be well tolerated by users. Chlorhexidine gluconate (CHG)–containing antiseptic handwash products have been able to meet the TFM criteria, but other antiseptic ingredients, such as 60% isopropanol, when properly formulated, can also meet the TFM criteria while also providing excellent moisturization. OBJECTIVES: To evaluate the effectiveness of a 60% isopropanol hand rub in a HCPH clinical study and to evaluate the moisturizing properties in a forearm controlled application test (FCAT). METHODS: To determine efficacy, a randomized, double-blinded HCPH study was designed based on the procedures described in the TFM. Following a 1-week washout period, Serratia marcescens was applied to the subjects' hands followed by the application of the 60% isopropanol hand rub or the positive control (4% CHG). The contamination/application cycle was repeated 10 times. Reduction of the test organism was determined after cycles 1, 3, 7, and 10. A randomized, double-blinded FCAT study was designed to determine the moisturizing properties of the isopropanol hand rub versus skin lotions. The test products were applied twice, 30 minutes apart, to the subjects' forearms. Transepidermal water loss (TEWL) and skin hydration were evaluated at baseline, 1, 2, and 4 hours after the second applications. RESULTS: In the HCPH study, the 60% isopropanol hand rub exceeded the TFM criteria by achieving a 4.11 log10 reduction of the test organism from baseline after wash 1 and a 4.41log10 reduction after wash 10 (p = 0.0001). This compared to 2.42 log10 and 3.62 log10 reductions for the 4% CHG product. In the FCAT study, the 60% isopropanol hand rub significantly decreased transepidermal water loss (p = 0.0071) and significantly increased skin hydration (p = 0.0001). CONCLUSION: These data demonstrate that a well formulated 60% isopropanol hand rub can meet the TFM criteria for a HCPH and provide moisturizing properties comparable to typical hand lotions used in healthcare facilities. BACKGROUND: A healthcare personnel handwash (HCPH) is defined in the Tentative Final Monograph for Healthcare Antiseptic Drug Products (TFM) as an antiseptic handwash that demonstrates a 2 log10 reduction of a marker organism, Serratia marcescens, after wash 1 and a 3 log10 reduction after wash 10. In addition to the rapid, broad-spectrum efficacy requirements, antiseptic handwash products should be formulated to maintain skin condition and should be well tolerated by users. Chlorhexidine gluconate (CHG)–containing antiseptic handwash products have been able to meet the TFM criteria, but other antiseptic ingredients, such as 60% isopropanol, when properly formulated, can also meet the TFM criteria while also providing excellent moisturization. OBJECTIVES: To evaluate the effectiveness of a 60% isopropanol hand rub in a HCPH clinical study and to evaluate the moisturizing properties in a forearm controlled application test (FCAT). METHODS: To determine efficacy, a randomized, double-blinded HCPH study was designed based on the procedures described in the TFM. Following a 1-week washout period, Serratia marcescens was applied to the subjects' hands followed by the application of the 60% isopropanol hand rub or the positive control (4% CHG). The contamination/application cycle was repeated 10 times. Reduction of the test organism was determined after cycles 1, 3, 7, and 10. A randomized, double-blinded FCAT study was designed to determine the moisturizing properties of the isopropanol hand rub versus skin lotions. The test products were applied twice, 30 minutes apart, to the subjects' forearms. Transepidermal water loss (TEWL) and skin hydration were evaluated at baseline, 1, 2, and 4 hours after the second applications. RESULTS: In the HCPH study, the 60% isopropanol hand rub exceeded the TFM criteria by achieving a 4.11 log10 reduction of the test organism from baseline after wash 1 and a 4.41log10 reduction after wash 10 (p = 0.0001). This compared to 2.42 log10 and 3.62 log10 reductions for the 4% CHG product. In the FCAT study, the 60% isopropanol hand rub significantly decreased transepidermal water loss (p = 0.0071) and significantly increased skin hydration (p = 0.0001). CONCLUSION: These data demonstrate that a well formulated 60% isopropanol hand rub can meet the TFM criteria for a HCPH and provide moisturizing properties comparable to typical hand lotions used in healthcare facilities.