Pegaspargase /pəˈɡæspərɡeɪz/, trade name Oncaspar, is a modified enzyme used as an antineoplastic agent. It is a form of L-asparaginase which has undergone PEGylation. The drug is manufactured by Exelead, Inc. Pegaspargase /pəˈɡæspərɡeɪz/, trade name Oncaspar, is a modified enzyme used as an antineoplastic agent. It is a form of L-asparaginase which has undergone PEGylation. The drug is manufactured by Exelead, Inc. It is used in the treatment of acute lymphoblastic leukemia. PEGylation