Dexfenfluramine

Dexfenfluramine, formerly sold under the brand name Redux, is a serotonergic drug that was used as an appetite suppressant to promote weight loss.^[2] It is the d-enantiomer of fenfluramine and is structurally similar to amphetamine, but lacks any psychologically stimulating effects.

Dexfenfluramine was, for some years in the mid-1990s, approved by the United States Food and Drug Administration (FDA) for the purposes of weight loss. However, following multiple concerns about its cardiovascular side effects,^[2] the FDA withdrew the approval in 1997.^[3] After it was removed in the US, dexfenfluramine was also pulled out in other global markets. It was later superseded by sibutramine, which, although initially considered a safer alternative to both dexfenfluramine and fenfluramine,^[4][5][6] was likewise removed from the US market in 2010.^[7][8]

The drug was developed by Interneuron Pharmaceuticals, a company co-founded by Richard Wurtman, aimed at marketing discoveries by Massachusetts Institute of Technology scientists.^[9] Interneuron licensed the patent to Wyeth-Ayerst Laboratories.^[10] Although at the time of its release, some optimism prevailed that it might herald a new approach,^[11] there remained some reservations amongst neurologists, twenty-two of whom petitioned the FDA to delay approval. Their concern was based on the work of George A. Ricaurte, whose techniques and conclusions were later questioned.^[12]