title: Initial results of a phase I trial of continuous infusion SR 2508 (etanidazole): a radiation therapy oncology group study.
abstract: To exploit both the oxygen-mimetic and "pre-incubation" or continuous exposure effects of the 2-nitroimidazole radiosensitizers, we are conducting a Phase I trial of continuous infusion SR 2508 for patients receiving brachytherapy. Following the administration of a loading dose of 2 g/m2, SR 2508 is administered by continuous infusion for 48 hr. Twenty-one patients have completed treatment. The initial total dose was 8 g/m2 with patients currently receiving 15 g/m2. No toxicity has been observed. At the higher doses the steady-state plasma concentrations have been between 50 and 70 micrograms/ml. It is not yet known whether or not hypoxic sensitizers will be of benefit clinically, and if so, when during a course of treatment is the optimal time to use them. Given the lack of toxicity and plasma concentrations achievable with continuous infusion, future studies will be conducted using SR 2508 during both the external beam and brachytherapy aspects of treatment.
authors.affiliation: Joint Center for Radiation Therapy, Harvard Medical School, Boston, MA 02115.
authors.forename: C N
authors.initials: CN
authors.lastname: Coleman
authors.forename: L
authors.initials: L
authors.lastname: Noll
authors.forename: A E
authors.initials: AE
authors.lastname: Howes
authors.forename: J R
authors.initials: JR
authors.lastname: Harris
authors.forename: J
authors.initials: J
authors.lastname: Zakar
authors.forename: R A
authors.initials: RA
authors.lastname: Kramer
mesh_terms: D001918:Brachytherapy; D003131:Combined Modality Therapy; D004341:Drug Evaluation; D017341:Etanidazole; D006801:Humans; D007262:Infusions, Intravenous; D009369:Neoplasms / Q000378:metabolism / Q000532:radiotherapy*; D009593:Nitroimidazoles / Q000008:administration & dosage* / Q000493:pharmacokinetics; D011838:Radiation-Sensitizing Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics
chemical_list: D009593:Nitroimidazoles; D011838:Radiation-Sensitizing Agents; D017341:Etanidazole