Frédéric Triebel (born 20 November 1954) is a French immunologist who is best known for his 1990 discovery of the LAG3 immune control mechanism.
Triebel worked through the 1990s in a collaboration between Institut Gustave Roussy and Merck Serono to establish LAG-3's mechanism of action in T cells and dendritic cells.
In 2001 he founded Immutep SA, a biotech company, to develop the therapeutic potential of LAG3.
In 2014 this company was acquired by Prima BioMed, where Triebel remains Chief Scientific and Medical Officer.