Highly loaded long-acting depots of therapeutic peptides

Peptides can have exquisite potency and selectivity in treating disease, but suffer from rapid clearance. Microparticle depot formulations, where the peptide is entrapped in a water-insoluble polymer matrix, have been tested for decades to provide sustained therapeutic release for chronic disease. The traditional microparticle structure has significant limitations, including low therapeutic content (lt5 wt%) and inadequate release profiles. Consequently, only 5 microparticle depots have been approved, representing 7% of marketed peptides. This application seeks to develop a long-acting microparticle depot formulation using the inverse Flash NanoPrecipitation (iFNP) platform being commercialized by Optimeos Life Sciences. iFNP enables the formation of polymer-coated peptide-loaded nanoparticles in a scalable and continuous manner. These nanoparticles are then clustered together to produce mechanically strong nanocomposite microparticles. The polymer coating surrounding each individual nanoparticle allows for much higher peptide loadings and more controlled, sustained release from the final microparticle.The iFNP technology has been validated using a model peptide, liraglutide, with therapeutic efficacy demonstrated in vivo for 1 month. The proposed research will apply the platform to three approved peptides that currently lack long-acting formulations. The three peptides treat chronic disease and possess varying physical properties. This proposed study will validate the universality of the platform and guide the selection of a lead candidate for development:1) Aim 1: Optimize encapsulation of three therapeutic peptide candidates in microparticle depots withloadings above 30 wt%2) Aim 2: Develop microparticle depots with sustained release profiles of active peptide over 1 month and3 months with minimized peptide degradation.The formulation design will build on the rules derived under an NSF STTR grant between Princeton University and Optimeos. Peptides tested to date have all been chemically modified to increase circulation time. The structure-encapsulation-release relationships identified in this work will advance our knowledge of suitable candidates for formulation by the platform. Stability studies, using LC-MS analysis, will identify amino acid residues with particular susceptibility to degradation that would be candidates for peptide modifications during lead optimization of formulation candidates. Crucially, the proposed work will translate to the sustained delivery of proteins, an application where no long-acting formulations are currently marketed.