title: Development of vaginal rings for sustained release of nonhormonal contraceptives and anti-HIV agents.
abstract: OBJECTIVE
  Construction of vaginal rings to deliver nonhormonal contraceptives and 3'-azido-3'-deoxythymidine (AZT) as an anti-HIV agent and determination of their daily release and efficacy in vitro.
  
  
  METHODS
  Intravaginal rings of 0.5-0.7 cm rim and 5-5.5 cm in diameter were cast in the molds. The rings were composed of biosoluble acacia gum or nonbiodegradable hydrogel of 2-hydroxyethyl methacrylate (HEMA) and sodium methacrylate (SMA) [P(HEMA-co-SMA)]. The rings were impregnated with nonhormonal contraceptives such as ferrous gluconate to cause spermiostasis, l-ascorbic acid to increase the viscosity of the cervical mucus, and pharmalytes of pH 4-5 or AZT.
  
  
  RESULTS
  The daily release rate of nonhormonal contraceptives as well as AZT from the rings was efficacious in vitro. Cumulative effect of nonhormonal contraceptives showed complete spermiostasis within 30 s up to 10 and 28 days, respectively. Daily release of AZT from both rings was also likely to be efficacious to inhibit HIV proliferation in vitro for 10 and 28 days, respectively.
  
  
  CONCLUSIONS
  The data indicate that the rings described here can be developed for intravaginal delivery of nonhormonal contraceptives and/or anti-HIV agents.
authors.affiliation: Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, Weill Medical College of Cornell University, 515 East 71st Street, S-412, New York, NY 10021, USA.
authors.forename: Young A
authors.initials: YA
authors.lastname: Han
authors.forename: Mukul
authors.initials: M
authors.lastname: Singh
authors.forename: Brij B
authors.initials: BB
authors.lastname: Saxena
mesh_terms: D019380:Anti-HIV Agents / Q000008:administration & dosage*; D001205:Ascorbic Acid / Q000008:administration & dosage; D002582:Cervix Mucus / Q000187:drug effects; D003271:Contraceptive Agents, Female / Q000008:administration & dosage*; D003274:Contraceptive Devices, Female; D016503:Drug Delivery Systems; D005260:Female; D005296:Ferrous Compounds / Q000008:administration & dosage; D006170:Gum Arabic; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008689:Methacrylates; D013094:Spermatozoa / Q000187:drug effects; D015215:Zidovudine / Q000008:administration & dosage*
chemical_list: D019380:Anti-HIV Agents; D003271:Contraceptive Agents, Female; D005296:Ferrous Compounds; D008689:Methacrylates; D015215:Zidovudine; D006170:Gum Arabic; D001205:Ascorbic Acid; C011819:ferrous gluconate