Animal only
This study developed a biodegradable buccal suction patch designed to improve the systemic delivery of peptide therapeutics by bypassing gastrointestinal degradation. Researchers replaced previously used non-degradable silicone materials with thermally crosslinked, synthesized copolyesters, fabricated via a scalable mold-casting process. Mechanical testing across multiple polymer formulations and patch shapes identified the best-performing biodegradable candidate, and degradation was confirmed in both aqueous media and simulated waste environments. An ex vivo model using porcine buccal tissue demonstrated that the biodegradable patch, when combined with a chemical permeation enhancer, improved permeation of a poorly permeable dye compared to controls. In an in vivo study conducted in beagle dogs, the patch substantially improved the bioavailability of semaglutide (4.11 kDa) relative to a commercially available oral tablet over a 10-minute application window. Additionally, the patch achieved a relative bioavailability of approximately 26% for bremelanotide (1.03 kDa) compared to subcutaneous injection. Limitations include the use of an animal model (beagle dogs) rather than human subjects, a small experimental scale, and the need for further clinical translation studies. The work highlights a potential sustainable alternative to silicone-based buccal delivery devices.
Journal of Controlled Release · Aug 2025
Animal only
This study introduces a biodegradable buccal suction patch designed to improve the systemic delivery of therapeutic peptides by bypassing gastrointestinal degradation. The researchers replaced previously used non-degradable silicone materials with biodegradable copolyesters, which were thermally crosslinked via a scalable mold-casting process. Mechanical testing identified the best-performing polymer formulation, and degradation was confirmed in both aqueous media and simulated waste environments. An ex vivo model using porcine buccal tissue demonstrated enhanced permeation of a poorly permeable dye when a chemical permeation enhancer was co-applied. In a beagle dog in vivo model, the biodegradable patch substantially improved the bioavailability of semaglutide (4.11 kDa) compared to a commercially available oral tablet within a 10-minute application window. The patch also achieved a relative bioavailability of approximately 26% for bremelanotide (1.03 kDa) versus subcutaneous injection. Key limitations include the use of an animal model rather than human subjects, a relatively small study scope, and the need for further safety and efficacy validation before clinical translation. The work highlights a promising, more sustainable alternative to silicone-based buccal delivery devices for peptide therapeutics.
Journal of controlled release : official journal of the Controlled Release Society · Jun 2025DOI ↗ Animal only
This study used female Syrian hamsters as an animal model to investigate how bremelanotide (Vyleesi), an FDA-approved drug for hypoactive sexual desire disorder (HSDD), affects the brain's reward system. Researchers examined melanocortin receptor (MC3R and MC4R) expression in the mesolimbic dopamine system — specifically the ventral tegmental area (VTA) and nucleus accumbens (NAc) — and assessed whether the drug enhanced sexual reward using a conditioned place preference (CPP) paradigm. Key findings attributed to the study include: MC4R mRNA was predominantly expressed in dopamine neurons in the VTA, while in the NAc and dorsal striatum, MC4R was rarely co-expressed with dopamine D1 or D2 receptor neurons, appearing instead in interneurons. Neither dose of bremelanotide tested altered melanocortin receptor mRNA expression in the mesolimbic system. Although sexual experience itself produced a CPP in female hamsters, bremelanotide did not enhance this sexual reward response. The authors conclude that bremelanotide does not appear to act through the VTA-NAc reward circuit in this model. A key limitation is that findings are derived entirely from an animal model and may not directly translate to human neurobiology or clinical outcomes.
Neuropharmacology · Jan 2025DOI ↗