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Index/Organizations/Janssen Pharmaceutica

Janssen Pharmaceutica

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Jan 4, 2026

was fentanyl first created in the u.s.

Fentanyl was not first created in the United States; it was synthesized and developed by Belgian chemist Paul Janssen at Janssen Pharmaceutica in the late 1950s/early 1960s, where the compound was fir...

Jan 4, 2026

where was fentenyl created first

Fentanyl was first synthesized and developed by Paul Janssen and patented by his company, Janssen Pharmaceutica; sources describe the compound’s laboratory creation around 1959–1960 and list a formal ...