Osteoarthritis affects millions who will experience the daily frustration of stiff, painful joints turned to heavy work by every simple move. Current treatments tend to mask symptoms or involve numerous injections that are lost as quickly as they can be administered. Fortunately, a new injectable hydrogel created by scientists at the University at Buffalo is set to turn the tables.
The starting material is a liquid that can be injected with a standard needle, and at body temperature it quickly solidifies into a soft, lubricating semi-solid depot. This depot brings an artificial cushion and reservoir, adheres to the joint surfaces, and gradually releases drug-loaded nanocarriers over many weeks. In fact, since many of the constituents of the hydrogel are already considered to be safe by regulators, the road to eventual clinical trial seems brighter than for many experimental treatments.
Osteoarthritis occurs when the slick cartilage that protects the ends of bones wears away over time. This breakdown is hastened by inflammation and aging cells, and results in the patient experiencing pain, swelling and decreased range of motion. The greatest challenge with pharmacologic therapy is the inability to maintain drug presence within the joint. The body’s natural lubricant, synovial fluid, clears injected drugs rapidly, oftentimes within hours. The Buffalo platform addresses this issue with dual mechanism of physical lubrication and prolonged, targeted drug delivery.
The injectable system has been demonstrated with a SIRT6 activator, a molecule that modulates cellular pathways known to be connected to inflammation and aging within intraarticular tissues. The researchers claim that the hydrogel could be tuneable to encapsulate other lipophilic disease-modifying molecules. In other words, one injection could be playing both the friction reducer, and a long term therapeutic agent designed to cascade some of the molecular changes behind it. This dual activity seems very exciting. As a viscosupplement, the hydrogel is restoring the joint to a less sticky glide. As a drug vehicle, it concentrates molecules of medicine at the painful site rather than dispersing them throughout the entire system.
That local application of the drug might mean fewer injection trips and a decreased risk of life-threatening reactions elsewhere in the body. For people who suffer repeated injections of hyaluronic acid or steroids, this has the possibility of producing sustained relief for a considerable period. Those performing the work note that the platform remains preclinical; additional studies need to be performed to identify the critical dose, validate safety, and test efficacy in larger animal models before proceeding to human trials.
Though, the early findings reveal a crucial setup shift. Rather than conceptualizing osteoarthritis as either a simple mechanical deterioration or solely an inflammatory state, the hydrogel strategy targets the joint both physically and biologically.