Adherence monitoring of vaginal ring for HIV prevention

Logger used: DST nano-T, temperature logger


Star-Oddi’s smallest temperature logger is being investigated as a component of a drug-releasing vaginal ring intended to protect women from HIV infection. The logger has significant potential in monitoring user adherence in clinical studies. The project, involving a partnership between the Queen's University Belfast (UK), the University of York (UK) and ProMed Pharma (qUS), is funded by the World Health Organisation (WHO).

Epidemic in Sub-Saharan Africa

The HIV/AIDS pandemic remains one of the most serious global public health crises of our time. The latest (2014) global statistics for HIV/AIDS estimate 37 million people living with HIV, 2 million new infections annually, and 1.2 million deaths in 2014 from AIDS-related illnesses. Sub-Saharan Africa remains the hardest hit region, accounting for more than 70% of people presently living with HIV/AIDS. Vaginal rings providing sustained release of antiretroviral drugs are at the forefront of prevention strategies. A silicone elastomer vaginal ring releasing dapivirine – a non-nucleoside reverse transcriptase inhibitor that targets replication of HIV  – has recently completed clinical testing and showed moderate levels of protection from sexually-transmitted HIV infection [1,2]. Unfortunately, women in the trial did not always use the ring as requested, and those who removed the ring were significantly more likely to become infected.

DST nano-T embedded in a vaginal ring

A previous study has shown that the DST nano-T, when embedded in silicone elastomer and inserted vaginally in macaques, was easily capable of detecting device removal and insertion events [3]. The results suggest that vaginal rings containing embedded temperature loggers may also be useful in the assessment of product adherence in late-stage clinical trials. A Phase I clinical study in women is scheduled to start early 2018 to further test the concept.


Additional Information and references

1. Nel A, van Niekerk N, Kapiga S, Bekker L-G, Gama C, Gill K, et al. Safety and Efficacy of a Dapivirine Vaginal Ring for HIV Prevention in Women. N. Engl. J. Med. 2016;375:2133–43.

2. Baeten JM, Palanee-Phillips T, Brown ER, Schwartz K, Soto-Torres LE, Govender V, et al. Use of a Vaginal Ring Containing Dapivirine for HIV-1 Prevention in Women. N. Engl. J. Med. 2016;NEJMoa1506110.

3. Boyd P, Desjardins D, Kumar S, Fetherston SM, Le-Grand R, Dereuddre-Bosquet N, et al. A temperature-monitoring vaginal ring for measuring adherence. PLoS One. 2015;10:e0125682.