Re: If the Lizard was the villain in Sam Raimi's Spider-Man 4...
By all accounts, it would have been the Vulture. However, to answer your question, I suppose something would have to push Curt into wanting to research regeneration. Then Curt would have to work alongside some researchers/corporation that would fund the research.
"I never asked for this crown. Gold is cold and heavy on the head, but so long as I am the king, I have a duty … If I must sacrifice one child to the flames to save a million from the dark … Sacrifice … is never easy, Davos. Or it is no true sacrifice." - Stannis Baratheon