Phase 3 is basically the definitive clinical trial. Phase 4 is essentially keeping track of what happens after your drug comes onto market. Once all of the resu

Phase 3 is basically the definitive clinical trial. Phase 4 is essentially keeping track of what happens after your drug comes onto market. Once all of the results are in, that paper will likely become the definitive paper on this particular drug (again, it's a bit weird that they did this prelim analysis without a clearly stated reason). So Phase 3 is the real deal in terms of winning approval to market the drug. Regarding efficacy, it is definitely low compared to many modern vaccines which are in the 90+ range. But my understanding is that this is much higher than previous malaria vaccines. If the numbers are really true, then they could possibly save hundreds of thousands of lives per year despite the relatively low efficacy. And it should be a first foothold in terms of making immunologic progress against Plasmodium.