post de BBALLGM, ya sabeis que respeto a este forero de Yahoo
What can I say...nothing is guaranteed in Phase III. And I lost a big part of my net worth on today's results, although a lot that net worth was made by Novavax. It sucks.
Anyways, we can either cry about it or analyze if this is salvageable. Well let's see.
There is definitely cause for concern. The re-dose phase II results are very strange....the Placebo-Vaccine group data is counter-intuitive because it is higher than the Vaccine-Vaccine group, yet it has worse efficacy data even with the highest titer.
Let's then look at the Phase III data. The vaccine group looks exactly like the placebo group, and that is not good. So the first question that comes to mind is why is it so different than the Phase II data. Why is the attack rate in Phase III less than HALF of what was seen in Phase II? I've been thinking about this for awhile, and it is a good thing they ran the re-dose trial because that also showed very low attack rate. So if we compared the placebo groups between the Phase III and Phase II redose trial, they match very closely...so this would indicate that indeed the attack rate is much lower for Phase III, just a chance of bad luck perhaps.
I would really want to the Kaplan Meir curve for this Phase III trial to see if it was really a low attack rate this season, or that Novavax started enrolling for the Phase III trial too late in the season. The original Phase II trial started in October 2014. The Phase III and Phase II redose trial both started in November 2015. So does 1-1.5 month difference in trial start make that big of a difference? It could be the reason for the lower attack rate. I want to see if the Kaplan Meir curve, and if there is a big drop at the beginning of the curve which may indicate the trial was started a bit late, and the RSV season has already started. Typically, RSV season onset starts in late October. Every season is a bit different, some start later and last longer.
What I mean by cocooning is that Novavax may have enrolled too many people within a short period of time within the same community. This may be a stretch, but something to look into.
If we look at the Phase III breakdown of enrolled patients...basically 100% of the enrolled are in community living...which is typical of elderly since they need assistance and probably living in group homes. And they probably tell each other about making some cash with being in the trial, so if I was Novavax, I would look at how close are the patients living with each other. The thought is that if they are all from the same neighborhood, and if the RSV vaccine is working, then the overall RSV incidence will be lower than usual. Since this is a virus, it needs hosts to spread the RSV, so 1 person infects 2 people, and those 2 people infect 4....so on and so on. Now if you start introducing a vaccine into a group of people who are in the same neighborhood, then you effectively lower the incidence rate because you stop the spread from the beginning. 60 sites for 12,000 people...so roughly 200 elderly per site. That's not too much considering how many elderly are there, but they need to look at if there are clusters of the enrolled living in the same community. Especially if they were being recruited heavily or if they go to the same elderly center. I've seen where they go to the elderly center, and just advertise to make some money, and the elderly is bused to the clinic in groups. Easy and quick recruitment. Just something to look into when the break down the site by site, and perhaps interview some patients on how they were recruited or look at the addresses / community centers.
If I was Novavax, I would start another Phase III trial, but I would want to start the enrollment at end of September/start of October, and perhaps spread out even more sites and make sure the recruitment is not from same community area.
Same goes for their Phase II redose trial
NVAX