Hylan G-F is an elastoviscous high molecular weight fluid containing hylan A and hylan B polymers produced from chicken combs. Hylans are derivatives of hyaluronan (sodium hyaluronate). Hylan G-F 20 is unique in that the hyaluronan is chemically crosslinked. Hyaluronan is a long-chain polymer containing repeating disaccharide units of Na-glucuronate-N-acetylglucosamine.

Hylan G-F is a gel-like mixture that comes in a syringe containing 6 mL (1 ½ teaspoon) and is injected into your knee. It is made up of hylan A fluid, hylan B gel, and salt water. Hylan A and hylan B are made from a substance called hyaluronan (pronounced hy-al-u-ROE-nan), also known as sodium hyaluronate that comes from chicken combs. Hyaluronan is a natural substance found in the body and is present in very high amounts in joints. The body’s own hyaluronan acts like a lubricant and a shock absorber in the joint and is needed for the joint to work properly.

Pharmacology

Joints contain a fluid, called synovial fluid, which acts as a lubricant and shock absorber. Patients with osteoarthritis have synovial fluid that is thinner than normal, and, therefore, it is less effective as a lubricant and shock-absorber. Hylan G-F 20 is an elastic fluid that is made from a substance called hyaluronan, that is found in normal joint fluid. Hyaluronan is the key substance in joint fluid that provides the shock-absorbing quality to the fluid, and it is essential for the proper functioning of joints. When Hylan G-F 20 is injected into the knee of a patient with osteoarthritis, the drug helps to restore the shock-absorbing effect of the fluid within the knee. This can reduce pain, resulting in a more active lifestyle.

2.25 mL glass syringe containing one 2 mL (16 mg) dose of hylan G-F 20. The contents of the syringe are sterile and nonpyrogenic.

Hylan G-F is indicated for the treatment of pain in osteoarthritis (OA) of the knee in patients who have failed to respond adequately to conservative nonpharmacologic therapy and simple analgesics, e.g., acetaminophen.

Hylan G-F 20 is administered by intra-articular injection once a week (one week apart) for a total of three injections. Strict aseptic administration technique must be followed.

• Using an 18- to 22-gauge needle, remove synovial fluid or effusion before each Hylan G-F 20 injection.
• Do not use the same syringe for removing synovial fluid and for injecting Hylan G-F 20 however the same 18- to 22-gauge needle should be used.
• Twist the tip cap before pulling it off, as this will minimize product leakage.
• To ensure a tight seal and prevent leakage during administration, secure the needle tightly while firmly holding the luer hub.

Do not administer to patients with known hypersensitivity (allergy) to hyaluronan (sodium hyaluronate) preparations. Do not inject Hylan G-F in the knees of patients having knee joint infections or skin diseases or infections in the area of the injection site

The most commonly reported adverse events associated with Hylan G-F 20 are the following: Pain in the injected knee, Swelling in the injected knee, Joint effusion

• The effectiveness of a single treatment cycle of less than three injections (2 mL each) of Hylan G-F 20 has not been established.
• The safety and effectiveness of Hylan G-F 20 in locations other than the knee and for conditions other than osteoarthritis have not been established.
• The safety and effectiveness of the use of Hylan G-F 20 concomitantly with other intra-articular injectables have not been established.
• Use caution when injecting Hylan G-F 20 into patients who are allergic to avian proteins, feathers, and egg products.
• The safety and effectiveness of Hylan G-F 20 in severely inflamed knee joints have not been established.
• Strict aseptic administration technique must be followed.
• STERILE CONTENTS. The syringe is intended for single use. The contents of the syringe must be used immediately after its packaging is opened. Discard any unused Hylan G-F 20.
• Do not use Hylan G-F 20 if package is opened or damaged. Store in original packaging (protected from light) at room temperature below 86°F (30°C). DO NOT FREEZE.
• Remove synovial fluid or effusion before each Hylan G-F 20 injection.
• Hylan G-F 20 should be used with caution when there is evidence of lymphatic or venous stasis in the leg to be injected.

Do not concomitantly use disinfectants containing quaternary ammonium salts for skin preparation because hyaluronan can precipitate in their presence. Do not inject Hylan G-F extra-articularly or into the synovial tissues and capsule. Local and systemic adverse events, generally in the area of the injection, have occurred following extra-articular injection of Hylan G-F. Intravascular injections of Hylan G-F may cause systemic adverse events.

Use in Special Populations

Pediatrics: The safety and effectiveness of Hylan G-F have not been established in pediatric patients. Pediatric patients are defined as patients ≤ 21 years of age.

Pregnancy & Lactation

Pregnancy: The safety and effectiveness of Hylan G-F 20 have not been established in pregnant women.

Nursing mothers: It is not known if Hylan G-F 20 is excreted in human milk. The safety and effectiveness of Hylan G-F 20 have not been established in lactating women.