Microbicides: A new hope for HIV prevention

Abstract

Human immunodeficiency virus (HIV), causative agent of acquired immunodeficiency syndrome (AIDS), is a global health concern. To control its transmission, safe sex has been proposed as one of the strategies. Microbicides- intravaginal/intrarectal topical formulations of anti-HIV agents have also been proposed to prevent HIV transmission. Microbicides would provide protection by directly inactivating HIV or preventing the attachment, entry or replication of HIV in susceptible target cells as well as their dissemination from target cells present in semen or the host cells lining the vaginal/rectal wall to other migratory cells. Microbicides must be safe, effective following vaginal or rectal administration, and should cause minimal or no genital symptoms or inflammations following long-term repeated usage. However, a safe and efficacious anti-HIV microbicide is not yet available despite the fact that more than 60 candidate agents have been identified to have in vitro activity against HIV, several of which have advanced to clinical testing. Nonetheless, proof-of-concept of microbicides has been established based on the results of recent CAPRISA 004 clinical trials. In this article, the trends and challenges in the development of effective and safe microbicides to combat HIV transmission are reviewed.

Anti-HIV-1 activity, protease inhibition and safety profile of extracts prepared from Rhus parviflora

“…The plant extracts or purified phytochemicals may exhibit anti-HIV activity by inhibiting virus entry/fusion, HIV-1 reverse transcriptase (RT), protease or its integrase activity [10-13]. Further, to prevent sexual transmission of HIV, microbicides with anti-HIV properties have been proposed that can be applied topically before sexual act [14]. …”

Clearance of Cervical Human Papillomavirus Infection by Topical Application of Curcumin and Curcumin Containing Polyherbal Cream: A Phase II Randomized Controlled Study

“…The various active ingredients in the formulation have anti-microbial, anti-inflammatory, anti-HPV and anti-HIV action (Gupta and Gupta, 2011). Basant TM inhibits the growth of Neisseria gonorrhoea, including those resistant to penicillin, tetracycline, nalidixic acid and ciprofloxacin (Talwar et al, 2008).…”

Microbicides and HIV: A Review and an update

“…[12] Besides, latest NACO and UNAIDS estimates have revealed that approximately 2.5 million people with HIV are in in India accounting for roughly half of Asia's HIV burden. [3]…”

“…However, HIV enters the superficial layers of the squamous epithelium by diffusing across a concentration gradient (mechanism known as “transmigration”, responsible for transmission of HIV from semen to vaginal epithelial cells) and gets sequestered their surface; and later infects CD4+ helper cells, Langerhans cells, dendritic cells, macrophages, and small Ki67 negative T cells (activated cells returning to resting state) found in mucosal epithelium. [38]…”