If you define success from a commercial standpoint, your assertion is guaranteed. There are only so many reimbursement dollars available in the aggregate for all cancer drugs, so it’s mathematically impossible for more than a tiny percentage of these drug candidates to be commercially successful.
There are exceptions, of course; however, all told, cancer-drug candidates are a sucker bet, IMHO.
First, like Peter, I'm heavily biased as the bulk of my biofolio is oncology-focused. But, I would submit that cancer-drug candidates may be a sucker's bet if you just plan on buying and holding long-term. I am by no means a short-term trader (you know I think TA is bunk), but there should be plenty of opportunities along the way to play the inevitable ebbs and flows in the biotech sector.
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