Hyaluronic Acid Technology
For nearly 30 years, Anika has developed products are based on hyaluronic acid (HA), also called hyaluronan or sodium hyaluronate. HA is present both in skin, where it plays a major role in tissue repair, and in cartilage and connective tissue, where it functions as a lubricant and a component of the extracellular matrix. HA is present in the body as a polymer (a linked chain of many individual HA units), is continually produced by hyaluronan synthases, and is degraded naturally by a category of enzymes called hyaluronidases.
HA is one of the main lubricating components of synovial joint fluid, and it has been shown to increase the viscosity of the overall mixture. HA is also an important component of cartilage, where it forms complexes that absorb water and help the cartilage maintain resiliency. The average 150-pound person has approximately 15 grams of HA within his or her body, nearly 5 grams of which are degraded and re-synthesized every day. The natural aging process leads to a decrease in the molecular weight of HA in cartilage. To combat this decrease, HA-based products developed for osteoarthritis (called Viscosupplementation products) assist in pain relief, and they also function to lubricate and cushion the joint.
Since naturally occurring hyaluronic acid (HA) is quickly degraded and resynthesized by the body, most HA-based therapeutics require stabilization. A common way to stabilize HA is to bind, or crosslink, HA polymers to other HA polymers, which functions to prevent their rapid, natural degradation. When crosslinked, the HA polymers increase in viscosity (thickness), and they convert from a liquid to a gel. The viscosity of this gel is determined by several factors, including the degree of crosslinkage between the HA chains. Crosslinked HA chains are still degraded by the body, but the degradation process takes several months as opposed to several hours. As a result, crosslinked HA-based therapeutics have the ability to remain stable in the body long enough to produce the desired therapeutic effect.
To achieve the desired increase in residence time, Anika has developed a proprietary chemical modification for crosslinking HA chains. This leads to a more durable material that remains in the body for a longer period and has enhanced mechanical properties.
Thanks to the chemical modification process known as esterification, Anika is able to create new classes of HA-derived biopolymers, known as HYAFF®. These biopolymers have controllable degradation rates which can be optimized depending on medical indication. They can also be easily processed into a variety of solid forms, while maintaining the excellent safety profile of hyaluronan.
Anika’s unique manufacturing technologies have allowed for the creation of different solid, implantable, biodegradable HYAFF-based products, including 3D non-woven scaffolds, that can be used in a variety of applications, such as cartilage regeneration and advanced wound care.