Bone-Promoting Thermoresponsive Macromolecules

PROPOSED TITLE

Bone-Promoting Thermoresponsive Macromolecules

NU 2016-201

INVENTORS

• Guillermo Ameer*
• Simona Morochnik

SHORT DESCRIPTION

Injectable, thermoresponsive PPCN-based hydrogels that are liquid at room temperature and gel at body temperature to provide controlled release of therapeutic agents and promote bone repair and formation.

BACKGROUND

The field of bone tissue engineering has focused primarily on replacing bone defects with inert or brittle materials. Current products, such as PMMA or calcium phosphate pastes, lack the ability to induce bone formation and often pose risks including inflammation and stress shielding. There is a growing unmet need for minimally invasive, bioactive, and adaptable materials that not only fill irregular fracture sites but also stimulate bone regeneration and enable localized drug delivery.

ABSTRACT

This invention describes injectable, thermoresponsive hydrogels based on poly(polyethylene glycol citrate-co-N-isopropylacrylamide) (PPCN) that remain liquid at room temperature and solidify at body temperature to form a controlled-release system. These hydrogels can incorporate therapeutic agents—including ions, drugs, or peptides—to actively promote bone formation and repair, or to treat bone diseases. Designed for orthopedic tissue engineering, the hydrogels are antioxidant and osteoinductive, enabling them to interact beneficially with the cellular environment even in non-osteogenic conditions. The versatility of the platform, including variants that display phosphate, cRGD, or strontium, allows for customized formulations to address diverse clinical needs in fracture repair, osteoporosis, and bone disease management.

APPLICATIONS

• Injection during orthopedic surgery: delivers the hydrogel directly to fracture or bone defect sites to accelerate healing
• Localized delivery of osteoporotic drug: enables controlled, site-specific drug release to combat bone resorption during surgery

ADVANTAGES

• Porous and bioactive structure: permits cell infiltration and drug delivery, unlike inert filler pastes
• Injectable softness: eliminates the risks of toxic monomers and stress shielding seen with PMMA
• Antioxidant properties: provides anti-inflammatory benefits essential for fracture healing
• Osteoinductive in non-osteogenic media: stimulates bone cell differentiation without the need for additional osteogenic supplements

IP STATUS

Issued US Patent 11,559,609; Nationalization filings in AU, CA, CN, EP, and JP