One creature? This is so situational it could have a free casting cost and still be underused. Namely, it would only be used to counter Aflatoxin. It wouldn't be worth a lick against Toadfish or Parasites, since the infection just renews, and it wouldn't be worth a lick against Plague since it hits all the creatures. It wouldn't even be worth the card space if you wanted to save your Otyugh from dying after having devoured a venomous creature, namely because it's going to be quinted, and just getting more Oty's would also be better.
A permanent would be much better, though it wouldn't be a new idea. Fountain of Youth would "refresh" a creature to restore it to its original state. This would be slightly different in that differences in stats would be retained, but other statuses would remain.