I have a good friend who is a cancer researcher and they're 5 years in and think they might be able to commercialize something in another 3. Realistically, they're assuming it will be closer to five.

While I have massive respect for the people with the insight, patience, and understanding to tackle biotech, I can't imagine spending 8-10 years for the hope that maybe you've done something useful.. and then figure out if you can sell it.