Phase IIb Trial

**Semantic type:** Research Activity

**Definition:** A clinical research protocol generally referred to as a well-controlled and pivotal trial that aims to prove the mechanism of action of the new intervention in question. A pivotal study will generally be well-controlled, randomized, of adequate size, and whenever possible, double-blind.

**Synonyms:** - 2B - PHASE IIB TRIAL - Trial Phase 2B - Trial Phase 2B - Trial Phase IIB - phase 2b