International Journal of Immunopharmacology vol:13 Suppl 1 pages:83-9
Several classes of non-nucleotide analogues (i.e. TIBO and HEPT derivatives) have been identified that specifically interact with the reverse transcriptase (RT) of human immunodeficiency virus type 1 (HIV-1). These derivatives inhibit the replication of HIV-1 in various cell lines, including peripheral blood lymphocytes and monocytes/macrophages, at concentrations that are 10,000- to 100,000-fold lower than the cytotoxic concentrations. At the HIV-1 RT level, they appear to interact with a specific allosteric "TIBO" site, which may be functionally and also structurally associated with the substrate binding site. The TIBO and TIBO-like compounds are orally bioavailable. In vivo they sustain plasma drug levels that are well above the concentrations required to inhibit virus replication in vitro.