- Selective pressure of a quinoxaline nonnucleoside inhibitor of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) on HIV-1 replication results in the emergence of nucleoside RT-inhibitor-specific (RT Leu-74-->Val or Ile and Val-75-->Leu or Ile) HIV-1 mutants. Kleim, J.P., Rösner, M., Winkler, I., Paessens, A., Kirsch, R., Hsiou, Y., Arnold, E., Riess, G. Proc. Natl. Acad. Sci. U.S.A. (1996)