Pure Food and Drug Act
The 1906 Act paved the way for the eventual creation of the Food and Drug Administration (FDA) and is generally considered to be that agency's founding date, though the agency existed before the law was passed and was not named FDA until later. "While the Food and Drug act remains a foundational law of the FDA mission, it's not the law that created the FDA. [Initially,] the Bureau of Chemistry (the precursor to the FDA) regulated food safety. In 1927, the Bureau was reorganized into the Food, Drug, and Insecticide Administration and the Bureau of Chemistry and Soils. The FDIA was renamed the FDA in 1930."
Orphan drug
The Pharmaceitical Executive opines, that the "ODA is nearly universally acknowledged to be a success".
Before the United States Congress enacted the ODA in 1983, only 38 drugs were approved in the USA specifically to treat orphan diseases. 
In the USA, from January 1983 to June 2004, the Office of Orphan Products Development 249 orphan drugs received marketing authorization and granted 1,129 different orphan drug designations, compared to fewer than ten such products in the decade prior to 1983. 
From 1983 until May 2010, the FDA approved 353 orphan drugs and granted orphan designations to 2,116 compounds. 
As of 2010, 200 of the roughly 7,000 officially designated orphan diseases have become treatable.