Calculation of the Median Lethal Dose and Low Lethal Dose Using the CombiStats Biometric Software

Abstract

The median lethal dose (LD50) and low lethal dose (LD10) are calculated in acute toxicity studies, as well as during specific activity assessment of some medicines. The aim of the study was to develop a procedure for using CombiStats to calculate LD50 and LD10. The authors proposed a step-by-step algorithm for processing bioassay results using the CombiStats biometric software (median effective dose determination model, probit analysis) with conversion of doses to simple fractions (fractions of the maximum dose) to calculate LD50 and LD10. They compared LD50 and LD10 calculation results obtained using CombiStats with those obtained using electronic spreadsheets according to the Bliss–Miller–Tainter–Prozorovsky method described in the State Pharmacopoeia of the Russian Federation (General Monograph 1.1.0014.15). It has been demonstrated that the use of CombiStats sometimes has advantages over the use of the pharmacoepoeial method.