Selection of human immunodeficiency virus type 1 resistance against the pyranodipyrimidine V-165 points to a multimodal mechanism of action.
OBJECTIVE
We have previously identified the pyranodipyrimidines (PDPs) as a new class of integrase (IN) inhibitors. The most potent congener V-165 inhibits HIV-1 integration at low micromolar concentrations by inhibiting the binding of IN to the DNA. As part of pre-clinical studies with PDP, we wanted to investigate HIV resistance development against V-165 and to further characterize the physicochemical properties of the compound.


METHODS
We selected PDP-resistant HIV-1 strains by growing the virus in the presence of increasing concentrations of V-165. The selected strains were analysed genotypically and phenotypically. Mutant IN enzymes were generated and evaluated in an enzymatic oligonucleotide-based assay for their activity and sensitivity to the different IN inhibitors. In addition, the antiviral effect of the compound on viral entry and integration was measured using quantitative PCR.


RESULTS
Numerous mutations were detected in the RT, IN and env genes of the virus selected in the presence of V-165. Although V-165 inhibited integration in vivo as indicated by a decrease in the number of integrated proviruses, the compound also inhibited viral entry at a concentration of 19 microM. V-165 was poorly recovered from human hepatic microsomal matrix and 1% BSA.


CONCLUSIONS
These data point to a multimodal mechanism of action. A quest for derivatives of V-165 that specifically target IN should be pursued.
Hombrouck
A
A
Laboratory for Molecular Virology and Drug Discovery, Katholieke Universiteit Leuven, Leuven, Flanders, Belgium.
Hantson
A
A
van Remoortel
B
B
Michiels
M
M
Vercammen
J
J
Rhodes
D
D
Tetz
V
V
Engelborghs
Y
Y
Christ
F
F
Debyser
Z
Z
Witvrouw
M
M
D019380:Anti-HIV Agents / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology*; D002460:Cell Line; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004279:DNA, Viral / Q000235:genetics; D024882:Drug Resistance, Viral / Q000235:genetics / Q000502:physiology*; D004797:Enzyme-Linked Immunosorbent Assay; D019302:HIV Envelope Protein gp160 / Q000235:genetics; D015658:HIV Infections / Q000821:virology; D054303:HIV Reverse Transcriptase / Q000235:genetics; D015497:HIV-1 / Q000187:drug effects*; D006801:Humans; D019426:Integrases / Q000235:genetics; D016086:Lentivirus / Q000235:genetics; D009841:Oligonucleotides; D010957:Plasmids / Q000235:genetics; D011714:Pyrans / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology*; D011743:Pyrimidines / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology*; D011995:Recombination, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014161:Transduction, Genetic
D019380:Anti-HIV Agents; D004279:DNA, Viral; D019302:HIV Envelope Protein gp160; D009841:Oligonucleotides; D011714:Pyrans; D011743:Pyrimidines; C522032:V-165 compound; D019426:Integrases; D054303:HIV Reverse Transcriptase