Microbicides 2004 Microbicides 200428-31 March 2004, Hilton London MetropoleThe conference42 million men, women and children worldwide were living with HIV by the end of December 2002 (source: UNAIDS), including five million newly-infected during that year alone. Another 45 million people will become infected between 2002 and 2010, unless the current transmission rates can be vastly reduced. Of the 42 million, 29.4 million live in sub-Saharan Africa and 58% of them are women. Not only are women more susceptible to HIV infection, many are powerless to insist on the use of condoms or other methods of protecting themselves. In this context, and with the knowledge that an effective HIV vaccine is unlikely to be available for several years, the need for an effective topical microbicide grows ever more urgent. 2004 should prove to be a landmark year in the field of microbicide development as the first Phase III trials of novel products are due to start – the next step along the road to making a microbicide available to the millions worldwide in desperate need of protection.The aims of the Microbicides 2004 conference are to:Report novel or innovative work in the microbicides fieldProvide updates on recent microbicides research, divided into three tracks: basic science, clinical science, and behavioural science (including public health and the microbicide marketplace)Provide a forum for the discussion of new developments in microbicide research including ethical, clinical, behavioural and methodological issuesPresent opportunities for knowledge-sharing between microbicide researchers, public-health workers and advocacy organisations.There will be an opening ceremony on the evening of Sunday 28 March at which politicians, policy makers and the international media are expected. The conference will run for a full three days, each of which will contain:Scientific overviews and presentations with plenary sessions, invited lecturers and presentations of original researchWorkshops to review issues unique to microbicides such as trial design and outcome measures, and ethical issues in the clinical trials of microbicidesPoster sessions. Focus on LondonFollowing the successful Microbicides conferences in Washington in 2000 and Antwerp in 2002, March 2004 sees the focus move to London.The venue is the Hilton Metropole Hotel, two minutes by taxi from Paddington station and the Heathrow Express, with a journey time from the airport of 15 minutes. The hotel is in walking distance of Hyde Park and London’s main shopping streets, and close to Imperial College. Accommodation will be available at the venue and other hotels in the vicinity.London in March offers a variety of diversions for out-of-conference relaxation, including sight-seeing and shopping; the arts and the theatre; and pubs, clubs and restaurants to suit every taste. Conference staff will be on hand to help delegates plan their spare time.To book your place or find out more information, e-mail info@microbicides2004.org.uk or telephone the Event Office on +44 (0) 20 7720 4411
Oral: invited speaker Oral: Track A Oral: Track B Oral: Track C Poster: Track A Poster: Track B Poster: Track C Abstract only Authors

02609 THE HEC PLACEBO: DESIGNED FOR “NO EFFECT”

Moench, Thomas R.*
Doncel G.F.†, and Cone R.A.¶*
*Reprotect, Inc, Baltimore, Md, †Conrad, Eastern Virginia Medical School, Norfolk, Va, ¶Johns Hopkins University, Baltimore, Md, U.S.A.

“Vehicle controls” are commonly used as placebos for two reasons: the vehicle (usually) provides a good physical match to the active product, and a vehicle placebo provides a comparison arm in which the absence of the active ingredient is the only difference between arms. Despite these common reasons for using the vehicle as the placebo, another consideration is arguably more important: the placebo must not cause unintended protection, and it certainly must not cause toxicity that increases susceptibility. Here we describe a placebo designed to minimize both protective and toxic effects. The design considerations included using: 1) a non-ionic gelling agent, HEC, (hydroxyethylcellulose) with no intrinsic microbicide properties (avoiding potentially active polyanionic gelling agents); 2) a preservative that is non-virucidal, non-inflammatory, and metabolizable (sorbic acid); 3) a formulation that has negligible buffering capacity (to avoid acid-mediated microbicidal effects even when formulated at pH ~4 to match the pH of the healthy vagina); and 4) a formulation that is isotonic to avoid causing an osmotic stress to the epithelium (and also to avoid the hypertonicity of many existing vehicle formulations, since hypertonic formulations cause osmosis that dilutes the gel and increases leakage from the vagina). In vitro studies document that the HEC Placebo has minimal cytocidal activity (by sperm motility and vaginal epithelial cell MTT assays), minimal stimulation of a proinflammatory response (IL-1 alpha release by vaginal epithelial cells), and minimal HIV inhibitory activity (2h virus-compound-cell incubation). In all four assays, the HEC Placebo had even less effect than K-Y® Jelly, a product that is generally assumed to be inert, and is commonly used as a control gel. In vivo experiments show that the HEC Placebo was not protective in an HSV-2 mouse vaginal challenge model. Moreover, unlike detergent spermicide/microbicides, when given 12 hours prior to HSV-2 challenge, it did not induce an increase in susceptibility to HSV-2. The minimal effects of the HEC Placebo should make it useful as a control gel for microbicide safety and efficacy trials

Dr. Thomas R. Moench
ReProtect, Inc, 703 Stags Head Road, Baltimore, MD 21286, USA
(Telephone) 410-337-8377 (Fax) 410-516-6597 (E-mail) tmoench@reprotect.com