An intravaginal ring for real-time evaluation of adherence to therapy

Preclinical contraceptive development for men and women

This manuscript endeavors to present research considerations for the preclinical development of non-hormonal contraceptives. Topics include (1) how advances in genomics and bioinformatics impact the identification of novel targets for non-hormonal contraception, (2) the importance of target validation prior to investment in a contraceptive development campaign, (3) considerations on targeting gametogenesis vs gamete maturation/function, (4) how targets from the male reproductive system are expanding women's options for 'on demand' contraception, and (5) some emerging non-hormonal methods that are not based on a specific molecular target. Also presented are ideas for developing a pipeline of non-hypothalamic-pituitary-gonadal-acting contraceptives for men and women while balancing risk and innovation, and our perspective on the pros and cons of industry and academic environments on contraceptive development. Three product development programs are highlighted that are biologically interesting, innovative, and likely to influence the field of contraceptive development in years to come.

Light-degradable hydrogels as dynamic triggers for gastrointestinal applications

Triggerable materials capable of being degraded by selective stimuli stand to transform our capacity to precisely control biomedical device activity and performance while reducing the need for invasive interventions. Here, we describe the development of a modular and tunable light-triggerable hydrogel system capable of interfacing with implantable devices. We apply these materials to two applications in the gastrointestinal (GI) tract: a bariatric balloon and an esophageal stent. We demonstrate biocompatibility and on-demand triggering of the material in vitro, ex vivo, and in vivo. Moreover, we characterize performance of the system in a porcine large animal model with an accompanying ingestible LED. Light-triggerable hydrogels have the potential to be applied broadly throughout the GI tract and other anatomic areas. By demonstrating the first use of light-degradable hydrogels in vivo, we provide biomedical engineers and clinicians with a previously unavailable, safe, dynamically deliverable, and precise tool to design dynamically actuated implantable devices.

Smart Freeze-Dried Bigels for the Prevention of the Sexual Transmission of HIV by Accelerating the Vaginal Release of Tenofovir during Intercourse

Sub-Saharan African women are still at risk from the human immunodeficiency virus (HIV), and sex with men is the main route of transmission. Vaginal formulations containing antiretroviral drugs are promising tools to give women the power to protect themselves. The aim of this work was to obtain freeze-dried bigels containing pectin, chitosan, or hypromellose for the vaginal controlled release of Tenofovir, which is accelerated in the presence of semen. Nine batches of bigels were formulated using different proportions of these polymers in the hydrogel (1, 2, and 3% w/w). The bigels obtained were freeze-dried and then underwent hardness and deformability, mucoadhesion, swelling, and drug release tests, the last two in simulated vaginal fluid (SVF) and SVF/simulated seminal fluid (SSF) mixture. The formulation containing 3% pectin (fd3P) has the highest values for hardness, resistance to deformation, and good mucoadhesivity. Its swelling is conditioned by the pH of the medium, which is responsive to the controlled release of Tenofovir in SVF, with the fastest release in the SVF/SSF mixture. fd3P would be an interesting smart microbicidal system to allow faster release of Tenofovir in the presence of semen, and thus increase women’s ability to protect themselves from the sexual transmission of HIV.