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

02689 EFFECTS OF SQUEEZING FLOWS ON DISTRIBUTION/RETENTION OF MICROBICIDE FORMULATIONS: EXPERIMENTAL SIMULATIONS & MATHEMATICAL MODELS

Kieweg, Sarah*
Katz, D.*,**
Departments of *Biomedical Engineering and **Obstetrics & Gynecology, Duke University, Durham, North Carolina, USA

Microbicide vaginal distribution depends on formulation properties, ambient fluids, vaginal geometry, and applied forces. Macroscopic forces – gravitational and squeezing – significantly affect vaginal coverage and retention. We characterize the macroscopic flows via experiments in vitro and theoretical mechanistic models. We measured rheological properties of 7 formulations: 3 cellulose gels (Conceptrol, Gynol II, and KY Jelly), 3 polyacrylic acid (PAA)-based gels (Advantage, KY Plus, and Replens), and a carrageenan gel (Carraguard). Squeezing experiments applied physiologically-relevant forces and monitored the resulting thickness and strain. Unlike cellulose and carrageenan gels, PAA gels exhibited yielding and non-yielding regions, as well as a limiting coating thickness, which ranked KY Plus > Replens > Advantage. For all gels, the coating was dependent on applied force and initial thickness (applied volume). The non-PAA gels experienced the most strain, with strain rankings: Carraguard > KY Jelly > Conceptrol/Gynol > Advantage > Replens > KY Plus. These strain rankings relate to squeezing distribution in vivo. Theoretical models of squeezing flows are compared to in vitro experiments and are used to specify formulation properties that optimize distribution and retention in vivo. For example, differences in rheological properties of Carraguard and KY Jelly may produce a 30% difference in epithelial coverage and a 40% difference in coating thickness. A 43% increase in applied volume may produce an 18% increase in coverage. The above results reveal large differences between formulations and suggest distribution differences in vivo due to squeezing flows. (Supported by NIH #AI48103)

Sarah L. Kieweg
Dept. of Biomedical Engineering, Duke University, Box 90281, Durham, North Carolina, 27708 USA
(Telephone) 919-660-5145 (Fax) 919-660-5362 (E-mail) sarah@duke.edu