Supartz and Synvisc are medications used to treat osteoarthritis of the knee. Orthopedic injectable Supartz is a product of Seikagaku Corporation and has been marketed in Japan since 1987 and in the United States since 2001. Supartz is sold in many countries under the names Supartz, ArtzDispo, Artz, or Artzal. Viscosupplements from Synvisc have been in use worldwide for more than 25 years and first gained approval in the United States in 1997. Synvisc is a product of Genzyme Biosurgery. While they are similar medications, there are some differences that patients considering these treatments should be aware of. Here’s how Supartz and Synvisc compare with each other.
What is knee osteoarthritis, and how does it develop?
Osteoarthritis is a joint disease that primarily affects the aging population. It is caused by the gradual breakdown of joint cartilage, which is a type of tissue that encloses and protects the ends of bones. Over time, the cartilage wears out to the point that the bones come into contact with each other. Subsequently, constant rubbing of the bones results in damage and the symptoms of pain, inflammation, and stiffness.
Osteoarthritis is the most common type of arthritis and, as mentioned above, is prevalent in the aging population. Major risk factors for this joint disease include gender, age, obesity, and previous injury. This disease represents a significant healthcare and economic burden to many patients due to disability, treatment costs, and the incidence of comorbidities. As a progressive, degenerative disease, knee osteoarthritis has no cure; rather, current medical therapies are adjunctive and are aimed at managing the symptoms of the disease with the goals of alleviating pain and improving joint function so that the patient can return to their daily activities.
How can medicines like Supartz and Synvisc help in the treatment of knee osteoarthritis?
Supartz and Synvisc belong to a group of medications known as viscosupplements. These hyaluronic acid-based products are administered to the knee to restore or supplement lubrication to the joint in order to protect against further damage to said joint and to help reduce adverse symptoms. They are usually given after the standard therapies used in osteoarthritis treatment, such as physical therapy and pain medications, have failed to produce adequate relief.
Patients with knee osteoarthritis have markedly different synovial fluid (the fluid in the joint that provides lubrication and shock-absorbing qualities to the knee) than healthy individuals. The fluid is usually reduced in quantity and has lower viscoelasticity, so it is thinner. This can be partially attributed to the decrease in concentration and size of hyaluronic acid molecules. Viscosupplements are meant to replenish hyaluronic acid in diseased synovial fluid and may even help stimulate the production of native hyaluronic acid. All of these aid in the relief of osteoarthritis symptoms in several ways, including the stimulation of chondrocyte metabolism, the inhibition of chondrodegradative enzymes and in?ammatory processes, and the production of articular cartilage matrix components.
In general, viscosupplements have been found to be effective in providing long-term relief and benefit to patients with knee osteoarthritis and are widely used and accepted as a form of treatment for knee osteoarthritis by many professional societies. Most viscosupplements have a delayed onset of treatment, taking several weeks to reach the full effects. However, the benefits are long-lasting: these medications can give up to six months of relief.
What are the differences between Synvisc and Supartz?
Synvisc and Supartz are similar to each other in many ways. In clinical studies, the efficacies of Synvisc and Supartz have been shown to be comparable to each other. However, there are some notable differences between the two products; they include the following:
• Dosing regimen: The main difference between Supartz and Synvisc is the number of injections required. Supartz is administered in a series of 35 weekly injections of 2.5ml each, while Synvisc is given in three injections of 2ml each that are administered one week apart. The number of injections can impact the choice of treatment, as the patient may not want the inconveniences and higher costs that comes with more visits to the doctor. Fewer injections also mean less chances of contracting a joint infection (septic arthritis), a distinct possibility that comes with any procedure involving injections. It should be noted that Synvisc is also available in a version that requires only a single injection to administer the full dose; this version is called Synvisc One.
• Composition: Synvisc (Hylan G-F 20) is made of highly cross-linked, avian-sourced hyaluronan, which itself is 80% hylan A and 20% hylan B, while Supartz is a solution of pure, high-molecular-weight sodium hyaluronate. Another aspect of note is that Supartz is made of unmodified sodium hyaluronate, while the hyaluronan of Synvisc has undergone cross-linking procedures in order to increase its molecular weight and residence time in the joint.
• Adverse event profile: Use of Synvisc has been linked with an increase of severe acute inflammatory reactions. This association has not been found in other viscosupplements, including Supartz. There is some evidence that the incidence of acute local reactions increases with successive injections and that these may be related to product-specific immunogenicity. This may be due to the manufacturing process of Synvisc, which uses formaldehyde and divinyl sulfone in its cross-linking process. The use of these chemicals has been shown to cause an immunological tissue reaction that can lead to incidences of pseudosepsis.
• Viscoelastic properties: Synvisc is thought to have viscoelastic properties that better resemble those of the synovial fluid of healthy, young adults. The viscoelasticity of the product is important to retain the joint rheological environment of a normal knee.
Viscosupplementation is a safe and often effective means to provide pain relief to patients with osteoarthritis of the knee. However, not all viscosupplements are the same: they can differ in terms of composition, manufacturing processes, rheological properties, and duration of effect. It is always a safe bet to consult with a doctor first before deciding on a treatment.