Efficacy of Postexposure Prophylaxis after Intravaginal Exposure of Pig-Tailed Macaques to a Human-Derived Retrovirus (Human Immunodeficiency Virus Type 2)

Abstract

Postexposure prophylaxis (PEP) after intravaginal exposure to human immunodeficiency virus (HIV) was investigated using the HIV type 2 (HIV-2)/pig-tailed macaque transmission model. PEP for 28 days with the reverse transcriptase inhibitor (R)-9-(2-phosphonylmethoxypropyl)adenine (PMPA; tenofovir) was initiated 12 to 72 h following HIV-2 exposure. Systemic infection was not evident in the 12-and 36-h groups, as defined by plasma viremia, cell-associated provirus, antibody responses, and lymph node virus. Breakthrough infection in the 72-h group was detected at week 16 post-virus exposure. These results demonstrate for the first time using a vaginal transmission model that early intervention after high-risk sexual exposures may prevent infection.

The use of a triple nucleoside‐nucleotide regimen for nonoccupational HIV post‐exposure prophylaxis

“…Once HIV crosses a mucosal barrier it may take up to 72 h before it is detected within the local lymph nodes and up to 5 days before it is detected in blood [1,2]. Animal studies have supported these biological models [3,4], with agents such as tenofovir showing reduced infection rates [5].…”

The clinical potential of the acyclic (and cyclic) nucleoside phosphonates. The magic of the phosphonate bond

“…prophylaxis of intravaginal exposure of pig-tailed macaques to HIV-2 [66], and (iii) protection of infection of newborn macaques against SIV [67] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 A c c e p t e d M a n u s c r i p t 1 2 3 4 5 6 7 8 9 10 11 1...…”

Use of Animal Models for Anti-HIV Drug Development

“…A similar study with AZT did not show protection 3 hours after intravenous SIV inoculation (Fazely et al, 1991). Later, vaginal transmission was largely prevented in macaques after tenofovir treatment began 12 or 36 hours post-challenge but not after 72 hours (Otten et al, 2000).…”