What was the hardest drug you had to correct before the doctors could use them on patients ?

Question: What was the hardest drug you had to correct before the doctors could use them on patients ?
- Keywords:
  doctor,
  drug,
  patient,
  recall
Asked by kirstt to Probash on 22 Mar 2011 in Categories: Your Research.
- Probash Chowdhury answered on 22 Mar 2011:
  
  I can’t go into specifics because those are the types of drugs that don’t make it to general release and we are not allowed to discuss them. I’ve worked on a medicine that was supposed to be given intravenously (into the vein by injection), but tests showed that it was too irritant and in the veins and the patients would not have been happy (that’s an understatement!). The doctors argued that the doses would be different and the speed that the injection was given could be adjusted, but I did some further work to show that this would eventually stop the irritation, but the drug would be so dilute that it wouldn’t work. The doctors gave in and that drug has not been tested on humans.
  
  There are others where I’ve made the chemist go back to the drawing board and start on new drugs too, but I can’t discuss those, sorry.

Question: What was the hardest drug you had to correct before the doctors could use them on patients ?