I am obviously not counting regular medicine like vaccines and antibiotics etc, they increase our likelihood of reaching the natural lifespan limit but do not extend the limit.
When they can show that some treatment extends the limit from around 120 to something like 150, then come back and talk about immortality. Although even then, there is a big difference between immortality and adding a mere 30 years! Oh, and those extra years had better not be as a bed bound senile in a nursing home. They can better be quality years, otherwise there is no point in bothering.