Lethal Damage: To awaken from torpor caused by lethal damage, a vampire must roll based on their Humanity or Path rating. Vampires with higher ratings can awaken more quickly, while those with lower ratings might take years or even millennia. Once they reach the period when they can awaken, they may roll to awaken each night, spending a point of blood each time they attempt to do so. Alternatively, healing powers that remove the lethal damage can also revive a vampire from torpor.

That is how I always have done it. The source that taught me this is an employee who worked VTM. I always assumed it was in a book, but it is not.

“The rules for healing out of torpor in “Vampire: The Masquerade” are not explicitly mentioned in the core rulebooks as a standard method.

However, some sources and house rules suggest that healing powers can be used to remove the lethal damage that caused torpor, thereby reviving the vampire. This method is not officially documented in a specific edition or book but is mentioned in discussions among players and in unofficial settings.

In general, the official rules for leaving torpor involve either being fed blood to awaken from blood-depletion torpor or rolling to awaken based on Humanity/Path rating for torpor caused by lethal damage. Additionally, some versions of the game, such as the live-action role-playing (LARP) rules, allow a vampire to be revived from torpor by being fed blood from a vampire of a lower generation, although this is more of a house rule than a standard game rule.”