Injectable drug depot engineered to release multiple ophthalmic therapeutic agents with precise time profiles for postoperative treatment following ocular surgery

• Published in: Acta biomaterialia 2018-06, Vol.73, p.90-102
• Main Authors: Mohammadi, Maziar, Patel, Kisha, Alaie, Seyedeh P., Shmueli, Ron B., Besirli, Cagri G., Larson, Ronald G., Green, Jordan J.
• Format: Article
• Language: English
• Subjects: Adrenal Cortex Hormones - chemistry; Adrenal Cortex Hormones - pharmacokinetics; Adrenal Cortex Hormones - pharmacology; Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - pharmacokinetics; Anti-Bacterial Agents - pharmacology; Antibiotics; Biodegradability; Biodegradation; Biomolecules; Block copolymers; Body temperature; Chemical compounds; Complications; Controlled release; Corticosteroids; Drug delivery; Drug delivery systems; Drug Implants - chemistry; Drug Implants - pharmacokinetics; Drug Implants - pharmacology; Eye; Formulations; Humans; Hydrogel; Hydrogels; Hydrogels - chemistry; Hydrogels - pharmacokinetics; Hydrogels - pharmacology; Hydrophobicity; Injectable; Injection; Injections; Microparticle; Microparticles; Ophthalmologic Surgical Procedures; Ophthalmology; Patients; Pharmacology; Poly(lactide-co-glycolide); Polyesters - chemistry; Polyesters - pharmacokinetics; Polyesters - pharmacology; Polyethylene glycol; Polyethylene Glycols - chemistry; Polyethylene Glycols - pharmacokinetics; Polyethylene Glycols - pharmacology; Polylactic acid; Polylactic Acid-Polyglycolic Acid Copolymer - chemistry; Polylactic Acid-Polyglycolic Acid Copolymer - pharmacokinetics; Polylactic Acid-Polyglycolic Acid Copolymer - pharmacology; Polylactide-co-glycolide; Postoperative; Postoperative Care; Postoperative period; Steroid hormones; Steroids; Surgery; Topical application
• ISSN: 1742-7061; 1878-7568
• DOI: 10.1016/j.actbio.2018.04.037

[Display omitted] A multi-drug delivery platform is developed to address current shortcomings of post-operative ocular drug delivery. The sustained biodegradable drug release system is composed of biodegradable polymeric microparticles (MPs) incorporated into a bulk biodegradable hydrogel made from triblock copolymers with poly(ethylene glycol) (PEG) center blocks and hydrophobic biodegradable polyester blocks such as poly(lactide-co-glycolide) (PLGA), Poly(lactic acid) (PLA), or Poly(lactide-co-caprolactone) (PLCL) blocks. This system is engineered to flow as a liquid solution at room temperature for facile injection into the eye and then quickly gel as it warms to physiological body temperatures (approximately 37 °C). The hydrogel acts as an ocular depot that can release three different drug molecules at programmed rates and times to provide optimal release of each species. In this manuscript, the hydrogel is configured to release a broad-spectrum antibiotic, a potent corticosteroid, and an ocular hypotensive, three ophthalmic therapeutic agents that are essential for post-operative management after ocular surgery, each drug released at its own timescale. The delivery platform is designed to mimic current topical application of postoperative ocular formulations, releasing the antibiotic for up to a week, and the corticosteroid and the ocular hypotensive agents for at least a month. Hydrophobic blocks, such as PLCL, were utilized to prolong the release duration of the biomolecules. This system also enables customization by being able to vary the initial drug loading to linearly tune the drug dose released, while maintaining a constant drug release profile over time. This minimally invasive biodegradable multi-drug delivery system is capable of replacing a complex ocular treatment regimen with a simple injection. Such a depot system has the potential to increase patient medication compliance and reduce both the immediate and late term complications following ophthalmic surgery. After ocular surgery, patients routinely receive multiple medications including antibiotics, steroids and ocular hypotensives to ensure optimal surgical outcomes. The current standard of care for postoperative treatment after ocular surgery involves using eye drops daily, which has limited effectiveness mainly due to poor patient adherence. To improve patient experience and outcomes, this article presents the first thermoresponsive hydrogel able to release multiple drug molecules fo