Let's aim for the so-called life extension escape velocity then. The cure may be even a 1000 years from now, but as long as you can keep extending your life to still be around then, it's fine.
'Even partially'? Such cures are found every day in the form of treatments for disease, healthy living rules, improvements in diet and exercise regimes.
If that. Many people say the reason cancer kills everyone eventually is that cells in our body wants to be free and it takes that this many generations to declare their independence and rebel against the perfectly tuned totalitarian system that is our body.