How successful will "longevity biotechnology" efforts be in extending human lifespan?

I saw a new tech term this week: longevity biotechnology company.  While the title seems self-explanatory, it did make me wonder how successful its efforts might be.  IMHO, we have been developing healthcare technology for many years, but life expectancy has fallen in recent years. And, at times, top healthcare technology has only been available to the wealthiest few. How successful do you think longevity biotechnology efforts will be in extending human lifespan?  
I understand this may be a sensitive topic in terms of politics and economics, and request respect in your comments.
Thank you!