definiens: means a clinical study of a drug candidate in hum an patients with the primary objective of characterizing its activity in a specific disease state as well as generating mor e detailed safety, tolerability, and pharmacokinetics information as described in 21 C.F.R. § 312.21(b ), or a comparable clinical study prescribed by the relev ant Regulatory Authority in a country other than th e United States including a human clinical trial that is also designed to satisfy the requirements of 21 C.F.R. § 312.21(a ) or corresponding foreign regulati ons and is subsequently optimized or expanded to satisfy the requirements of 21 C.F.R. § 312.21(b ) ( o r corresponding foreign 7 regulations ) or otherwise to enable a Phase 3 Clini cal Study ( e.g., a phase 1/2 trial ) . The relevant d rug candidate may be administered to patients as a sing le agent or in combination with other investigation al or marketed agents