As a result, a “rule-of-two” was defined that predicted see more hepatotoxicity more reliably when compared with dose alone. Applying the rule-of-two to the drug development process and to clinics will likely reduce

risk for DILI particularly in complex comedication. ADMET, absorption, distribution, metabolism, excretion, toxicity; ATC, Anatomical Therapeutic Chemical; CCR, correct classification rate; DILI, drug-induced liver injury; FDA, Food and Drug Administration; LTKB-BD, liver toxicity knowledge base benchmark data set; OR, odds ratio; OTC, over-the-counter; WHO, World Health Organization. Two publicly available drug databases were used to test for the relationship between lipophilicity, daily dose, and risk for DILI. The first data set is the liver toxicity knowledge base benchmark data set (LTKB-BD) recently published by MLN0128 mw our group17 that is available from the US Food and Drug Administration’s web site.18 It contains

287 drugs with the potential to cause liver injury as defined by the FDA-approved drug labels. Drugs were divided into three categories: most-DILI-concern, less-DILI-concern, and no-DILI-concern. The most-DILI-concern group contains drugs that were either withdrawn from the market due to hepatotoxicity or were assigned a black box warning for their potential to cause liver injury, or had a warnings and precautions section that specified concern about DILI that has a greater than moderate severity. The less-DILI-concern group contains drugs that specify a DILI concern in the warnings and precautions section with low severity or in an adverse reactions medchemexpress section, while the no-DILI-concern group comprised drugs with no DILI description mentioned in the labels. In the present study, we considered the most-DILI-concern (n = 116) and no-DILI-concern drugs (n = 48) (Supporting Table 1 and Supporting Fig. 1A). A second data set published

by Greene et al.19 was analyzed. The authors classified drugs into four groups, of which two groups were selected: those with evidence of hepatotoxicity in humans (hepatotoxic-positive) and those with no evidence of hepatotoxicity in any species (hepatotoxic-negative). Despite a difference in the approach to annotate a drug’s hepatotoxic potential, the concordance between the two data sets is high (∼90%).17 After removing drugs which overlapped with the LTKB-BD and mapping to the Anatomical Therapeutic Chemical (ATC) database of the World Health Organization (WHO), a total of 179 oral drugs remained of which 115 drugs were hepatotoxic positives and 64 negatives. The flowchart for drug inclusion is shown in Supporting Fig. 1B, and a full list of drugs is given in Supporting Table 2. Daily doses were retrieved from the WHO’s ATC database (http://www.whocc.no/atc_ddd_index), supplemented with FDA-approved drug labels (http://dailymed.nlm.nih.gov/dailymed/about.cfm) and literature searches.