Clokeran 2 (Chlorambucil 2mg) is a generic version of popular branded anti-cancer medications. The active ingredient Chlorambucil is used medication is used to treat certain types of cancer (such as leukemia, lymphoma). Chlorambucil belongs to a class of drugs known as Alkylating agents. It works by damaging the genetic material (DNA and RNA) of the cancer cells. This stops their growth and multiplication.