Laymen's Guide to RSV Elderly phase III Results
They came up this year with a new method called SPR to test the affinity of the PCAs.
* Affinity is the ability to neutralize RSV-F Site II, thereby neutralizing RSV.
* PCAs are Palivizumab Competing Antibodies that were generated by the immune system in response to NVAX RSV vaccine.
They used the SPR method to measure the affinity of the blood samples taken from vaccinated animals and people of preclinical, phases I, II, and III studies.
They found out that those who got a good affinity score also fought RSV infections very well. Those who got low score fought RSV poorly. This means the affinity test is a good predictor of vaccine efficacy. That is, now they can predict if the vaccine is efficacious simply by measuring affinity in the lab. You no longer need to wait for vaccinated subjects to catch RSV to find out if the vaccine is protective (efficacious). You can predict efficacy even if nobody caught RSV (zero attack rate). However, keep in mind that although this affinity test and its correlation with efficacy is powerful and reliable, it is nevertheless just an indication of the potential for success. The FDA will still expect NVAX to prove efficacy in phase III, where vaccinated people catch RSV and get only a bit sick or not sick at all.
Using the affinity test, NVAX found out that the vaccinated people in RSV elderly phase III did just OK, but not great. Based on affinity results the efficacy should have been about 30% (unsure of exact value, and don't really care -- it's not good). Then, why did we get ZERO efficacy result instead of about 30%? Answer: Because of LAR (Low Attack Rate). You need a good number of subjects to actually catch the real RSV before you can know for sure about efficacy. Thus, the LAR ruined the test, but the results would still have been poor even with a good AR.
I repeat: The LAR ruined the test, but the results would still have been poor even with a good AR.
Fortunately, there was a huge flag in the affinity results from the blood samples of all the past/present studies that pointed to this: Adding an adjuvant or giving a booster shot increased affinity to high levels.
Conclusion: It was a mistake to vaccinate the elderly with an unadjuvanted vaccine. Add adjuvant to NVAX RSV vaccine, and the vaccine would definitely be efficacious. You still need the AR to be not too low. To circumvent the effect of a LAR you could double the sample size from 12,000 to 24,000, or you could run the test in areas/groups that consistently have high AR. I think the latter is a better solution.
Hopefully, after you read this message, you'll realise why it's futile to lay blame on Stan, Greg or anyone else. Everyone was equally guilty. By "everyone", I mean NVAX, analysts, BioInvest and the experts of this board. At least we now have a bright light at the end of the tunnel. The stock will recover late next year when maternal results are out. Successful RSV maternal mean successful RSV for all age groups. The market will not wait for FDA approval or billions of dollars in sales. They'll rally the stock hard long before that. And, there is no need for dilution before end of next year. I'm pretty sure Stan will wait for maternal results before diluting, partnering or selling the company.