Summary
This is the first proof of concept that some protection can be achieved with a complex vaccine schedule using two products in prime-boost (sanofi-pasteur (EURONEXT: SAN and NYSE: SNY)and Global Solutions for Infectious Diseases with ties to VaxGen (OTCBB VXGN)).
This will not be a product &
Need to use these data to build next generation vaccine.
Need to share these data broadly to engage those who have left the field.
Analysis
This is a great step forward in the science, but not a product, for HIV prevention. On CNN yesterday, Tony Fauci quoted a p value of 0.039 for the difference in cases. This suggests (although I haven't seen the data first hand) that the lower bound confidence limit is very close to zero. Dr. Fauci further went on to say that the science is important but that we are a long way from a product and I agree.
And, we only get to a product if the data in this trial are such that they help define a correlate of protection in those very small differences in cases. At that point, then, we can translate those differences into an enhanced next generation set of products that will move the protective efficacy to north of 50%. And a minimum of 50% efficacy will likely be needed.
Having been away from HIV for some time, I am also struck by the less than 1% attack rate in the placebo group over 3 years among this "high risk" population. Does this mean that other protective measures are having an effect or has the attack rate in high risk populations always been below 1%? Were these folks more likely to have other STDs treated and/or prevented more aggressively because of the trial and by that had their attack rate reduced? I appreciate comments on this.
This small step must be followed by answering questions and sharing information if we are truly going to make progress towards a licensable vaccine and re-engaging vaccine developers who have left the field because of the previous failures. Those questions relate to the following:
And, we only get to a product if the data in this trial are such that they help define a correlate of protection in those very small differences in cases. At that point, then, we can translate those differences into an enhanced next generation set of products that will move the protective efficacy to north of 50%. And a minimum of 50% efficacy will likely be needed.
Having been away from HIV for some time, I am also struck by the less than 1% attack rate in the placebo group over 3 years among this "high risk" population. Does this mean that other protective measures are having an effect or has the attack rate in high risk populations always been below 1%? Were these folks more likely to have other STDs treated and/or prevented more aggressively because of the trial and by that had their attack rate reduced? I appreciate comments on this.
This small step must be followed by answering questions and sharing information if we are truly going to make progress towards a licensable vaccine and re-engaging vaccine developers who have left the field because of the previous failures. Those questions relate to the following:
1. Are we confident the groups were balanced for risk factors?
2. What clades of HIV were seen and were there differences between clades?
3. Were there any subsets (e.g. gender) that had better or worse protection?
4. What serologic data exists in those infected and how does that compare to data in those uninfected that might point to an immune correlate?
5. What do viral loads look like in the two infected populations (vaccine vs. placebo), any suggestion of "benefit" there?
Frank Malinoski consults with leading institutions through GLG
Analyses are solely the work of the authors and have not been edited or endorsed by GLG.
