A werewolf is a lycanthrope, a human who is afflicted by a curse that causes them to forcibly transform into a man-wolf beast under the full moon. Warwick has NEVER been a true werewolf. Ever.
Old Warwick drank a potion given to him by Singed, and became a half-wolf man beast. He has no capacity to transform back to his human form, and his mind slowly became more feral as time passed in his new form. That's why he wanted to get Soraka's heart, so he could use another potion to stabilize his mind from become a complete beast. He was, again, NEVER a true werewolf because he never experiences transformations on a cyclical basis. He just is the wolf beast.
Jump over to new Warwick. Same general principle, except Singed forcibly turns a regular man into a man-wolf beast. He's not a true werewolf either, because he's not under a curse that causes his human form to transform.
So nothing has changed that dramatically about Warwick, because he's still a scientifically created man-wolf beast.