text: Schering AG filed for a patent for NETA in June 1957, and the patent was issued in December 1960. The drug was first marketed, by Parke-Davis as Norlestrin in the United States, in March 1964. This was a combination formulation of 2.5 mg NETA and 50 μg ethinylestradiol and was indicated as an oral contraceptive. Other early brand names of NETA used in oral contraceptives included Minovlar and Anovlar.