Poly(caprolactone)-based subcutaneous implant for sustained delivery of levothyroxine

This work aimed to develop a subcutaneous implant for prolonged delivery of LEVO treat hypothyroidism. could overcome challenges with patient compliance and co-administration improve treatment this condition. For purpose, implants were produced by solvent casting mixtures poly(caprolactone) (PCL), poly(ethylene glycol) (PEG) sodium. These contained PCL differing molecular weight, PEG different sodium loadings (20% or 40% w/w). SEM images confirmed that the drug was evenly dispersed throughout implant. In vitro release rates ranging from 28.37 ± 1.19 – 78.21 19.93 µg/day 47.39 8.76 98.92 4.27 achieved formulations containing 20% w/w loading, respectively. Implants higher amounts low weight showed profiles governed zero order kinetics. On other hand, high mechanism Fickian diffusion. Finally, two representative tested in vivo . capable providing detectable levels plasma during entire duration experiments (4 weeks) between 5 20 ng/mL.