Referring to the US FDA clinical trial phase 2 protocol for patients with major depressive disorder, Summarize primary & secondary efficacy objectives and their associated endpoints, including a summary of exploratory or other endpoints that are relevant to the demonstration of goals of the phase 2 study necessary to proceed to phase 3 confirmatory trials.

referring to another phase 2 clinical trail protocol for the same indication is major depressive disorder, provide an assessment of each of the design elements and primary & secondary objectives & endpoints that summarize above. Are each of these appropriate for phase proof-of-concept study? If so, why? If not, why not? Comment on whether endpoints in this protocol would be appropriate to use in phase 3 confirmatory studies. For example, some phase 2 studies use biomarkers/surrogate endpoints to establish proof-of-concept & confirmatory phase 3 studies use clinical endpoints.