(447d) Composite Deoxycholic Acid-Based Microparticles for Localized Adipose Tissue Reduction with Reduced Inflammation

Excess adipose tissue can lead to various physical health concerns and body image issues. Deoxycholic acid is an FDA-approved treatment for removing adipose tissue, initially proposed as a safer injectable solution than standard yet risky surgical procedures such as liposuction. However, limited efficacy, excessive doses, and severe injection site inflammation have impeded the success of this drug formulation. Recently, microparticles composed of bile salts and gold nanoparticles have been shown to lyse adipocytes in vitro and in vivo with lower inflammation than the clinically used deoxycholic acid treatment. Here, we describe the long-term local reduction of adipose tissue by subcutaneous injection of deoxycholic acid-based composite microparticles using an optimized dosing scheme. These composite microparticles release the active drug and gold nanoparticles over time through surface erosion to curb inflammation and cause fewer side effects at the injection site. We demonstrate that these particles significantly reduce adipose tissue mass over 4 weeks post-injection in an obese mouse model with a subcutaneous injection and contralateral control. Additionally, the particle therapy exhibits reduced inflammation and associated immune cell infiltration compared to deoxycholic acid solution, observed through histology and cytokine levels within the adipose tissue. Any increase in inflammation for the particle treatment is completely resolved by 4 weeks post-injection, as shown in Figure 1. Finally, we show that a second dose of particle therapy after 4 weeks can further reduce adipose tissue mass. Overall, deoxycholic acid-based composite microparticles promise to deliver an effective and safer injectable therapy for local adipose tissue reduction with fewer treatments.