An erratum is published for the article "Aptamers as therapeutics" by Anthony D. Keefe, Supriya Pai, and Andrew Ellington in Nature Reviews Drug Discovery 9, 537–550 (2010). The erratum corrects the address provided for Anthony D. Keefe. The correct address is X-Chem Incorporated, 100 Beaver Street, Waltham, Massachusetts 02453, USA.An erratum is published for the article "Aptamers as therapeutics" by Anthony D. Keefe, Supriya Pai, and Andrew Ellington in Nature Reviews Drug Discovery 9, 537–550 (2010). The erratum corrects the address provided for Anthony D. Keefe. The correct address is X-Chem Incorporated, 100 Beaver Street, Waltham, Massachusetts 02453, USA.