3SO9:
reference: The higher barrier of darunavir and tipranavir resistance for HIV-1 protease., Wang Y, Liu Z, Brunzelle JS, Kovari IA, Dewdney TG, Reiter SJ, Kovari LC, Biochem Biophys Res Commun. 2011 Sep 9;412(4):737-42. Epub 2011 Aug 17. PMID: 21871444

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