I don't think this point gets mentioned enough: since physical degeneration due to aging is such a big risk factor for so many diseases, anything we can do to reverse that degeneration could end up being hugely effective at preventing some of the diseases of old age. And there's a surprising lack of investment in this, probably because discussions tend to get bogged down in lengthy, heated philosophical digressions about how long people should want to live.

If you're looking for medical miracles, this is a very plausible place to find them.