Lomustine (INN), abbreviated CCNU (original brand name (formerly available) is CeeNU, now marketed as Gleostine), is an alkylating nitrosourea compound used in chemotherapy. It is closely related to semustine and is in the same family as streptozotocin. It is a highly lipid-soluble drug and thus crosses the blood-brain barrier. This property makes it ideal for treating brain tumors, which is its primary use. Lomustine has a long time to nadir (the time when white blood cells reach their lowest number).
Unlike carmustine, lomustine is administered orally. It is a monofunctional alkylating agent, alkylates both DNA and RNA, has the ability to cross-link DNA. As with other nitrosoureas, it may also inhibit several key enzymatic processes by carbamoylation of amino acids in proteins. Lomustine is cell-cycle nonspecific.
In 2014, the drug was re-launched and rebranded as Gleostine, manufactured by NextSource Biotechnology.