Phosphoramide mustard
from cyclophosphamide
“Mustard alkylates DNA”
What it isThe DNA-crosslinking metabolite of cyclophosphamide and ifosfamide.
Why it mattersIt is the species that actually alkylates DNA — the parents are inert until CYP activates them.
What it changes⛑ Acrolein, the other product of that activation, causes the hemorrhagic cystitis. Mesna binds acrolein and does not touch this.
NO BOXED WARNINGS
Principal riskAcrolein from the same activation causes cystitis