Praxeus antidote

The Praxeus antidote was the antidote to the Praxeus virus. Its a genetically-engineered virus created by the Thirteenth Doctor using enzymes from Earth birds infected by Praxeus. After the cure worked on Adam Lang, the Doctor's TARDIS replicated it and the Doctor and her companions spread the cure into the jet streams using Suki Cheng's ship, ending Praxeus on Earth. However, the cure is only designed for humans and the Doctor warned Suki that no only was it unlikely to work for Suki's species, but it could have disastrous effects on them. This was shown when Suki herself attempted to use the cure only to die shortly after. (TV: Praxeus)