The adverse event (AE) profile observed in the extension study was consistent with that observed during the pivotal trial. Gastrointestinal symptoms were the most common AE, reported in 63% (12/19) of patients in the extension study. Transient aminotransferase elevations (ALT or AST) =3x the upper limit of normal (ULN) occurred in nine of the patients who completed Week 126 of the extension study either in the pivotal phase or the extension phase or both, including five patients who had elevations =5x ULN. Of these patients, one patient had an ALT elevation of 24x ULN that was reversible with temporary suspension of lomitapide, and a second patient had a reversible ALT elevation of =10--20x ULN following co-administration of other drugs that may precipitate liver injury or interact with lomitapide. One patient who used excessive alcohol was withdrawn due to persistent ALT elevations =5x ULN. No Hy's law cases were reported.