Once or Twice Daily Administration of BIIB021 to Subjects With Advanced Solid Tumors

Heat shock protein 90 (HSP90) inhibitors are anticipated to have clinical activity in solid tumors because Hsp90 is required for the folding, activation, and assembly of many proteins involved in cancer cell survival, proliferation, and metastasis. The maximum tolerated dose (MTX) for BIIB021 administered twice weekly in a phase I study in subjects with advanced solid tumors have been defined at 600mg. It is now reasonable from a safety perspective and desirable from a pharmacokinetic perspective to evaluate more frequent dosing intervals in solid tumors with the goal of providing more sustained and completed inhibition of Hsp90.