If you have a drug on hand, then its not uncommon it takes +10 years to get it to market.
Sure regenerative medicine got a "fast track" but its still takes many years to get from discovery to a phase 2 conditional market release. We still have to see a treatment going from discovery to conditional market release within 5 years.
Are we then taking FDA approval into account, and condense that down to ONLY clinical trails, we are talking +5 years. We also need to take into account that FDA needs to do final approval which takes almost a year (if you are a "Priority Review", so we are beyond +6 years. All of this if it all the stars aligns and no problems are met during the trails, like all test subjects are available on day 0 (which they rarely are), supply chain is consistent, and data analysis take 1 day and we do all clinical days back to back, and again have test subjects on day 0.
So the rule of thumb with +10 years isn't far of. And that is, when its almost smooth sailing.