NEWARK, N.J. (AP) — Four people, including former executives at two drug companies, have pleaded guilty to running an insider trading scheme.

John Lazorchak, a former director of financial reporting at Summit-based Celgene Corp., and Mark Cupo, who held a similar position at Sanofi-Aventis, a France-based company with U.S. headquarters in Bridgewater, each pleaded guilty in federal court Monday to five counts of securities fraud.

Two high school friends of Lazorchak’s, Michael Pendolino of Nashua, N.H., and Mark Foldy of Morris Plains, also pleaded guilty. Pendolino pleaded guilty to one count of conspiracy and Foldy pleaded guilty to three counts of securities fraud and one count of conspiracy.

The defendants were arrested last November and charged with exploiting deals involving Celgene, Sanofi and other companies. They are scheduled to be sentenced in January.