Tipranavir is an anti-retroviral that has very much improved activity. Tipranavir binds to conserved amino acids of the Protease that can't be mutated without the enzyme losing its function. Tipranavir has more comformation than most current protease inhibitors. Tipranavir is similiar to Atazanavir and Lopinavir, which are very improved. Tipranavir also makes direct bonds with the Isoleucine 50 amino acids at each subunit of this homodimer.