For the last few decades, scientists have been searching for cures to cancer. There are 5 companies now that, while not offering a cure, are offering what might be a safer therapy for different kinds of cancers - a cancer vaccine. These 5 companies are now in a race to see which one's Phase III clinical trial returns positive results first.
It's rather exciting news, and highlights just how tense a Phase III trial can be, especially when most of your predecessors in the theory have not been successful.
In a Phase I trial, companies are trying to show basic safety - that it won't hurt people, and a look at dosage safety. In a Phase II trial, companies are demonstrating the efficacy of the drug - that it likely will do what you think it should do. In Phase III, the number of enrolled subjects is multiplied many times the number involved in Phase II, to show that it works over a broader spectrum of people (Stats 101 - bigger the sample size, generally the more reliable the results).
Cancer vaccines are tricky creatures, and have only been seriously pursued in the last several years. It should be fascinating to see which, if any, of the 5 that are in play now will really work.
One issue that has been bugging me is the notion of what would be deemed a "positive result" that would merit FDA approval. Therion Biologics Corp.,for instance, is developing a vaccine for pancreatic cancer, and is looking for "positive results." Clearly, if there is absolutely no difference in immune response between those receiving a placebo and those receiving the vaccine, the vaccine will not be approved (at least, I would be shocked ... who would use it in that case?). But what is the actual threshold? 30% increased immune response? What is 30% of the people show a much more increased response, and 70% show no delta from the placebo?
Perhaps I'm showing my inner geekdom (or lawyer-like tendency toward worry-wartness?), but these are the kinds of issues that just captivate me. Well, and likely interest the industry analysts, too, as they try to play the game of "what will let this drug get on the market and drive up that individual stock as well as the stock of similar drugs?"
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