Zopiclone
Zopiclone was developed and first introduced in 1986 by Rhône-Poulenc S.A., now part of Sanofi-Aventis, the main worldwide manufacturer. Initially, it was promoted as an improvement on benzodiazepines, but a recent meta-analysis found it was no better than benzodiazepines in any of the aspects assessed. On April 4, 2005, the U.S. Drug Enforcement Administration listed zopiclone under schedule IV, due to evidence that the drug has addictive properties similar to benzodiazepines.
Dimethisterone
Dimethisterone was developed by the British pharmaceutical company British Drug Houses (which subsequently merged with Merck KGaA) and was first reported in the medical literature in 1959, with introduction for medical use under the brand name Secrosteron following in the same year. It was introduced in the United States as an oral contraceptive in combination with high doses of ethinylestradiol under the brand name Oracon (25 mg dimethisterone, 100 μg ethinylestradiol) in 1965. Due to the fact that it contains a weak progestogen in combination with a large dose of a potent estrogen, this preparation was eventually found to be associated with a substantially increased risk of endometrial cancer in women, and is now no longer marketed.