Estimate of the safe starting dose in clinical trials for therapeutics in adult healthy volunteers

A strategy was proposed to determine the maximum recommended starting dose (MRSD). Usually, no observe adverse effect level (NOAEL) from the relevant animal studies should be converted to the human equivalent dose (HED) using standard factors. Using sound scientific judgments, the MRSD is determined by dividing the HED from the most appropriate species by the safety factor. This strategy pertained to determining the MRSD of any new drug or biological therapeutic that had been studied in animals, but was not pertinent to prophylactic vaccines or endogenous proteins used at physiologic concentrations.