Just as our own Birdman predicted back in November, a wedge design is now favored. Here is the whole transcript -- but this it the bit you need to read:
. . . .Dr. Anne Schuchat, the director of the National Center for Immunizations and Respiratory Diseases: Maybe I could share a little bit from the perspective of the [Merck/GSK] trial being planned for Sierra Leone. We have modified some of the aspects of our design to increase its flexibility and to increase the chance that we will be able to measure the efficacy given the likelihood for fewer -- for lower rates of disease. This has involved switching from a fixed size of enrollment to an event-driven design where we will be able to have rolling enrollment and expand or extend the duration.
So, much of the design remains but rather than having the number of [shots] fixed, we will have an event drive design. And rather than a fixed amount of vaccination we have ability to expand to more people. This also addresses the reality that we won't be able to start as early as we would have liked to. So rather than people being vaccinated pretty much systematically throughout the trial period we will be trying to front load a lot of vaccinations and also have more people vaccinated towards the end of the trial. Again, people will be randomized for the time of immunization, not to either a vaccine group or a control group. We will try to get more people vaccinated earlier than with the previous draft design. That said, we are working closely across the partnerships and making sure that we take advantage of these candidates being ready to go and also don't cut corners.
We, like the NIH, have set up a data monitoring board that is reviewing closely both design and progress. . . .
More as it develops. We will keep you apprised.