- less than 4 weeks since last anti-cancer therapy (including chemotherapy, biologic/immunologic, radiation) or less than 6 weeks if prior therapy was with nitrosourea or mitomycin (for therapies with prolonged effects, a treatment-free interval of at least 2 half-lives should be considered) with the exception of the following: Treatment with thalidomide, dexamethasone, lenalidomide (Revlimid®), and/or bortezomib (Velcade®) is allowed up to 7 days prior to the first dose of G-CF.