Onakpoya IJ, Spencer EA, Thompson MJ, et al. Effectiveness, safety and costs of orphan drugs: an evidence-based review. BMJ Open 2015;24;5:e007199. There have been corrections to the online supplement as follows:

In Appendix 1, Orphacol has been added to the list, and the appropriate references used in the quality and level of the evidence for Orphacol and Cholic Acid FGK are:

• Cholic Acid FGK: European Medicines Agency. Assessment report. Cholic acid FGK. http://www.ema.europa.eu/docs/en_GB/document_library/EPAR_-_Public_assessment_report/human/002081/WC500165386.pdf

• Orphacol: European Medicines Agency. Orphacol, INN-cholic acid - Annex 1. Summary of product characteristics http://www.ema.europa.eu/docs/en_GB/document_library/EPAR_-_Product_Information/human/001250/WC500150993.pdf

In Appendix 2, table 2, the authors have revised the indications for Orphacol, and added ‘deficiency’ to the indication for Cholic Acid FGK:

• Cholic Acid FGK: IEM in primary bile acid synthesis due to Sterol 27-hydroxylase deficiency.

• Orphacol: IEM in primary bile acid synthesis due to 3beta-Hydroxy-delta5-C27-steroid oxidoreductase deficiency or delta4-3-Oxosteroid-5beta-reductase.

In Appendix 2, table 2, and in Appendix 3, the authors have revised the annual cost of Litak to £835 (1 cycle) based on correspondence with the manufacturers.