In 1962, writer James Gunn published a collection of interwined short stories entitled The Immortal about the exploits of Dr. Russell Pearce and his (and others') encounters with Marshall Cartwright and his progeny. Seems Mr.Cartwright has a rare blood type that keeps him and his children from aging or dying and getting sick. A transfusion of his blood not only cures the recipient of any affliction they're suffering but also temporarity restores their youth as well. Of course, this makes Cartwright and his offspring very valuable to the rich and powerful, who use every resource available to track them down.
Author Gunn updated the novel (including mentioning AIDS and adding a brand new short story, "Elixir") in 2004, renaming the collection The Immortals. Even with the updating, the book still packs a wallop, especially in the current health care reform debate. Gunn raises a number of interesting questions about the medical profession and its impact on society, as well as giving the reader an exciting, tension-filled narrative that never flags in it's pacing.
You can reserve The Immortals online here.