It's included in Running Wild. (Trust me, I triple checked my draft and every developer looked for it too.)
For the time being, treat it as blocking Regeneration (Don't regen the wounds from a weapon made with it, and don't regen if still in direct contact) and a Severe Allergy for DVs/Dice pool modifiers when exposed.
Unlike Alleviate Allergy, there are no known spells for alleviating a Vulnerability.
AH's post about it can be found
HERE.