Each trial has a specific indication and a single drug candidate. As mentioned earlier, we consider single drug clinical trials. Trials with greater than one indication or those that present ambiguity in the assignment of a specific indication are excluded from this study. Targets that can be mapped to the drug and can be linked mechanistically to the disease associated with the trial, present an exclusive set of 'efficacy targets' . It is generally accepted that an unambiguous assignment of a specific drugtarget interaction responsible for the therapeutic activity is evasive. Nonetheless, we have used bioactivity data for drug-target association only when the target has been implicated through direct evidence with the disease in question. Many drugs have promiscuous mechanistic effects, and hence using efficacy targets as an indicator will include a statistical aggregating component across the available multi-target bioactivities . Statistical measures to enumerate bioactivities have been used previously, towards other goals . Nonetheless, due to stringent exclusion criteria (see Section 2), the intersection of two manually curated resources, DrugBank and CTD to derive this list, resulted in 80% of the trials we have used in this dataset having a maximum of two targets in common with drug and indication as shown in Section S7.4 of Supporting Information. This implies the model will perform better in predicting trial outcomes of drugs with known mechanisms of action, in other words, validated efficacy targets.