title: A temperature-monitoring vaginal ring for measuring adherence.
abstract: BACKGROUND
  Product adherence is a pivotal issue in the development of effective vaginal microbicides to reduce sexual transmission of HIV. To date, the six Phase III studies of vaginal gel products have relied primarily on self-reporting of adherence. Accurate and reliable methods for monitoring user adherence to microbicide-releasing vaginal rings have yet to be established.
  
  
  METHODS
  A silicone elastomer vaginal ring prototype containing an embedded, miniature temperature logger has been developed and tested in vitro and in cynomolgus macaques for its potential to continuously monitor environmental temperature and accurately determine episodes of ring insertion and removal.
  
  
  RESULTS
  In vitro studies demonstrated that DST nano-T temperature loggers encapsulated in medical grade silicone elastomer were able to accurately and continuously measure environmental temperature. The devices responded quickly to temperature changes despite being embedded in different thickness of silicone elastomer. Prototype vaginal rings measured higher temperatures compared with a subcutaneously implanted device, showed high sensitivity to diurnal fluctuations in vaginal temperature, and accurately detected periods of ring removal when tested in macaques.
  
  
  CONCLUSIONS
  Vaginal rings containing embedded temperature loggers may be useful in the assessment of product adherence in late-stage clinical trials.
authors.affiliation: School of Pharmacy, Queen's University Belfast, Belfast, Northern Ireland, United Kingdom.
authors.forename: Peter
authors.initials: P
authors.lastname: Boyd
authors.affiliation: CEA, Division of Immuno-Virology, DSV/iMETI, IDMIT Center, Paris, France; UMR-E1, Paris Sud University, Orsay, France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Desjardins
authors.affiliation: School of Pharmacy, Queen's University Belfast, Belfast, Northern Ireland, United Kingdom.
authors.forename: Sandeep
authors.initials: S
authors.lastname: Kumar
authors.affiliation: School of Pharmacy, Queen's University Belfast, Belfast, Northern Ireland, United Kingdom.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Fetherston
authors.affiliation: CEA, Division of Immuno-Virology, DSV/iMETI, IDMIT Center, Paris, France; UMR-E1, Paris Sud University, Orsay, France.
authors.forename: Roger
authors.initials: R
authors.lastname: Le-Grand
authors.affiliation: CEA, Division of Immuno-Virology, DSV/iMETI, IDMIT Center, Paris, France; UMR-E1, Paris Sud University, Orsay, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Dereuddre-Bosquet
authors.affiliation: Star-Oddi Ltd, Gardabaer, Iceland.
authors.forename: Berglind
authors.initials: B
authors.lastname: Helgadóttir
authors.affiliation: Star-Oddi Ltd, Gardabaer, Iceland.
authors.forename: Ásgeir
authors.initials: Á
authors.lastname: Bjarnason
authors.affiliation: World Health Organization, Department of Reproductive Health and Research, Geneva, Switzerland.
authors.forename: Manjula
authors.initials: M
authors.lastname: Narasimhan
authors.affiliation: School of Pharmacy, Queen's University Belfast, Belfast, Northern Ireland, United Kingdom.
authors.forename: R Karl
authors.initials: RK
authors.lastname: Malcolm
mesh_terms: D000818:Animals; D001831:Body Temperature; D002986:Clinical Trials as Topic; D003274:Contraceptive Devices, Female / Q000009:adverse effects / Q000592:standards*; D005260:Female; D008252:Macaca fascicularis; D012826:Silicone Elastomers; D013821:Thermometers
chemical_list: D012826:Silicone Elastomers