What the heck? [Two-Stage / GS Designs]

posted by Helmut Homepage – Vienna, Austria, 2012-07-03 21:25 (4286 d 15:49 ago) – Posting: # 8883
Views: 19,542

Hi ElMaestro!

❝ I am reading FDA's draft guidance on Loteprednol, revised June 2012.


At least that’s the first official statement that the FDA accepts sequential designs and prefers Potvin etc. Can revise my presentations from “personal communication with Barbara Davit”. :-D

❝ "[…] if there is no intention to separately submit to the Agency the results of the first group, then a second group may be enrolled following analysis of data from the first group, and statistical analysis conducted using “group” in the model without using the sequential design constraints."


❝ Whiskey Tango Foxtrot?


Precisely.

❝ What does that mean for an applicant and does anyone have some insight into the logic behind it?


What the heck does the “if – then – without” part mean? Why should anybody want to submit the results of stage 1 if he/she/it has to proceed to stage 2? Any if not, what does “without using the sequential design constraints” mean? Unbelievable – with FDA’s Donald Schuirmann as co-author of both papers.
Reading between the lines my interpretation would be: FDA accepts a pilot study (classical design, n ≥ 12, properly planned and evaluated, etc.) demonstrating already BE. So the pilot is treated as a pivotal study. If a study passes in stage 1, FDA calls this one pivotal.

Dif-tor heh smusma 🖖🏼 Довге життя Україна! [image]
Helmut Schütz
[image]

The quality of responses received is directly proportional to the quality of the question asked. 🚮
Science Quotes

Complete thread:

UA Flag
Activity
 Admin contact
22,957 posts in 4,819 threads, 1,636 registered users;
110 visitors (0 registered, 110 guests [including 4 identified bots]).
Forum time: 12:15 CET (Europe/Vienna)

With four parameters I can fit an elephant,
and with five I can make him wiggle his trunk.    John von Neumann

The Bioequivalence and Bioavailability Forum is hosted by
BEBAC Ing. Helmut Schütz
HTML5