Ann: Invex Granted Type C Meeting with FDA, page-92

it’s a binary outcome. if it gets one trial this will fly, but if it’s gets two trials it’ll get very close to cash backing of 40 cents.

in terms of your question, the answer lies in powering the study appropriately for the outcome being measured. The regulator needs well controlled studies in order to deem a drug efficacious.

for invex, their phase 2 study can serve as a phase 2/3 study given that they proved safety outcomes whilst also pushing clear efficacy outcomes in vision and headaches. The question now comes in the form of seeing if the FDA is accepting of one confirmatory trial for a headache outcome, or whether they need two seperate trials to be sure that presendin is efficacious.