Replies to post #195679 on Innovation Pharmaceuticals Inc (IPIX)

[noretreat]

there is no evidence that what you say is what happened.

[untohim]

for late-stage trials, the methods with the most momentum are those which use conditional power to define an interim analysis as “promising” and based on this allow adjustment to bring the conditional power to the target power via increased sample size, stimulating increased interest in adaptive designs from clinical, academic, and regulatory parties. The theory suggests that when a result is “promising” the standard test statistics from both the standard fixed term and group sequential tests can be usable without adjustment while still not inflating the overall error levels of the study. Another adaptive design which will likely see continued growth is seamless designs in early and late stage clinical trials with an associated growth in the methods and resources to estimate and re-estimate the sample size for these designs.

[sox040713]

Adding 10 patients meant a change in protocol and should require IRB approval (see K Phase 1), so I don't think safety was a concern in the two P arms. IPIX probably requested this change several weeks in advance since IRB usually meets once every two weeks. So the adaptive design of adding more patients to the 400 mg arm could be a reason.