In the early 2010s I had a couple friends working at a biotech startup with a moonshot cancer cure. They had amazing results in animal testing, and had raised just enough funding to do a first human trial on a terminal patient.

That patient was hit and killed by a car two days after finishing their treatment.

Along with the CEO's stubborn refusal to give up any more equity in the company, they went under, and the world will never know if that treatment worked.