ChEMBL is an open, manually-curated, large-scale bioactivity database integrating data records extracted from medicinal chemistry literature, from deposited data sets, as well as other public data sources. It brings together chemical, bioactivity and genomic data to aid the translation of genomic information into effective new drugs. Information regarding the compounds tested (including their chemical structures), the biological or physicochemical assays performed on these and the targets of these assays are recorded in a structured form, standardized, and annotated with controlled vocabularies to allow users to address a broad range of drug discovery questions.