You picked the worst example possible.
Medicine is one of the most tightly regulated fields in the world with huge upfront cost and approval processes spanning years or even decades. E.g. the research and approval process of a new antibiotic costs multiple billion dollars before it can be sold.
What you see now wrt the Covid-19 vaccine is an international effort that is fast-tracking everything. Regulators are willing to overlook a lot for it to come to market as fast as possible and it's still taking a year or more before it's approved for use on everybody.
Uncertainty – there is never 100% certainty when determining reasonable assurance of safety and effectiveness of a device. However, the degree of certainty of the benefits and risks of a device is a factor we consider when making benefit-risk determinations.
And regulation in no way - in no way - addresses the fact that medicine isn't close to 100% safe before adoption, and neither should self-driving cars be. As long as they are safer than humans, that's enough. Any other conclusion will cost lives.
Nothing is 100% safe. By your logic we’d have no medicine, have you ever read the side effects of some medicines.