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.
Buspirone
Buspirone was first synthesized, by a team at Mead Johnson, in 1968, but was not patented until 1975. It was initially developed as an antipsychotic drug acting on the D receptor, but was found to be ineffective in the treatment of psychosis and was repurposed as an anxiolytic. In 1986, Bristol-Myers Squibb gained FDA approval for buspirone in the treatment of GAD. The patent placed on buspirone expired in 2001 and it is now available as a generic drug.