Glad to hear that you are a LT survivor of leukemia. There are different forms of that disease, but many are among the most treatable forms of cancer.
What the FDA needs to see with DCVax is a difference in progression-free survival for those who got the vaccine versus those who did not. If the data can show that, then the company will get an approval. If the data does not show that, the company probably won't get approved. The waters have been muddied with all this discussion of blended and blinded data which does not allow anybody to make the required analysis so we just have to wait for the data.
Equally relevant, but often overlooked, is the cost/benefit ratio. This will be an expensive intervention, but it may or may not be cost effective. Lets say, hypothetically, that a course of therapy will cost $100K but it only prolongs life by 1 week. That increase in life may be statistically measurable and may result in an approval, but insurance may refuse to pay for it. If, on the other hand, the increase in survival is one year, then that is a different discussion entirely.
Both FDA approval and payor economics depend on squeaky clean statistics so that the company can make its best case with hard data that is 100% credible. So far that data has not been forthcoming so any conjecture about what the final results will look like remains entirely speculative and speculation is generally not a good investment thesis except for the highest risk part of your portfolio.