All depends on what sort of return the investor is seeking.
e.g.
50-100x outlay: then you'll absolutely need to hold through results and probably to licensing and first revenue. But there's substantially more risk in holding into results.
5-10x outlay: for me this is the best trade-off, on a risk/reward basis, if you have patience.
You get in early, when nobody is overly interested, buy loose shares after placements etc and wait. With each significant announcement that arrives, the stock is slightly more de-risked and you still usually get profit taking, which makes it hard for the sp to make much inroad. As the company draws closer to significant clinical outcomes, the market begins to wake-up.
You get all the benefits of irrational exuberance, as the market starts to price the probability of success into the sp. You let it keep bubbling along and more often than not, if you've held for a good 12-24 months, you'll be sitting on a 5-10 bagger. For me, that's the time to exit most of the position. You've held with relatively minimal risk and have enjoyed all the benefits of great returns. I don't know a less risky method of making $50-100k on a $10k investment.
The problem i see with many people on the forums is that they significantly overstate the probability of success, based on earlier trials the company has run and smart marketing. They let their endless desire to retire early/become wealthy through windfall, dictate their decision making process, rather than accepting that, much like mineral exploration, most bios never make it - not the other way around. These are all fairly understandable human emotions (who wouldn't want to retire early, for example) but it's important that novice traders/investors actually understand the risks involved. PBT, for example, had several members commenting that they took the risk and knew it wasn't certain and were disappointed. Fair enough. However there were also those who were clearly distressed by the outcome, of which they thought was all but certain and there were also some experienced members on the threads, who did nothing to extinguish that irrational optimism and moreover fueled it.
It's the old story of buyer beware and do some basic research and have a strategy that you stick to, as the market usually displays the same features, regardless of the stock.
