Legend Injection (Canada)

Company: Boehringer Ingelheim Animal Health

(hyaluronate sodium)

Sterile Injection

VETERINARY USE ONLY

For intravenous or intra-articular use in horses only

DIN 02169541

Description

LEGEND^® (hyaluronate sodium) Injection is a clear, colorless solution of low viscosity. It is administered by intravenous or intra-articular injection.

LEGEND^® Injection is extracted from the capsule of Streptococcus spp. and purified, resulting in a pure form of hyaluronate sodium which is essentially free of protein and nucleic acids. The solution is pyrogen free, sterile, and does not contain a preservative.

LEGEND^® Injection is supplied in 2 mL (20 mg) vials and in 4 mL (40 mg) vials. Medicinal ingredient per mL: 10 mg hyaluronate sodium. Non-medicinal ingredients per mL: 8.5 mg sodium chloride, 0.223 mg sodium phosphate dibasic and 0.04 mg sodium phosphate monobasic. The pH is adjusted to between 6.5 and 8.0 with sodium hydroxide or hydrochloric acid.

CHEMISTRY: Glycosaminoglycan, commonly referred to as hyaluronic acid, can exist in the following forms depending upon the chemical environment in which it is found: as the acid, hyaluronic acid; as the sodium salt, sodium hyaluronate (hyaluronate sodium); or as the hyaluronate anion. These terms may be used interchangeably but in all cases, reference is made to the glycosaminoglycan composed of repeating subunits of d-glucuronic acid and N-acetyl-D-glucosamine linked together by glycosidic bonds. Since this product originates from a microbial source, there is no potential for contamination with dermatan or chondroitin sulfate or any other glycosaminoglycan.

Pharmacology

Hyaluronic acid is a naturally occurring substance present in connective tissue, skin, vitreous humour and the umbilical cord in all mammals. High concentrations of hyaluronic acid are also found in the synovial fluid. It also constitutes the major component of the capsule of certain micro-organisms. The hyaluronic acid produced by bacteria is of the same structure and configuration as that found in mammals.

The actual mechanism of action for hyaluronate sodium in the healing of degenerative joint disease is not completely understood. One major function appears to be the regulation of normal cellular constituents. This effect decreases the impact of exudation, enzyme release and subsequent degradation of joint integrity. Additionally, hyaluronate sodium exerts an anti-inflammatory action by inhibiting the movement of granulocytes and macrophages.¹

Hyaluronate molecules are long chains which form a filter network interspersed with normal cellular fluids. It is widely accepted that injection directly into the joint pouch enhances the healing of inflamed synovium by restoring lubrication of the joint fluid. This further supplements the visco-elastic properties of normal joint fluid.

Contraindications

There are no known contraindications for the use of LEGEND^® (hyaluronate sodium) Injection in horses.

Safety in breeding animals has not been determined with LEGEND^® Injection.

TOXICOLOGY: LEGEND^® Injection was administered to normal horses at one, three and five times the recommended intra-articular dosage of 20 mg and the intravenous dosage of 40 mg. Treatments were given once weekly for nine consecutive weeks (three times the maximum duration). No systemic clinical signs were observed nor were there any adverse effects upon hematology or clinical chemistry parameters. A transient, slight to mild post-injection swelling of the joint capsule occurred in some of the animals treated intra-articularly with LEGEND^® Injection as it did in the saline treated control horses. No gross or histological lesions were observed in the soft tissues or the surface areas of the treated joint.

SIDE EFFECTS OR ADVERSE REACTION: No local or systemic side effects were observed in the clinical field trials with either intravenous or intra-articular injections.

Legend Injection Caution

Radiographic evaluation should be carried out in cases of acute lameness to ensure that the joint is free from serious fractures. As with any intra-articular treatment, special precautions must be followed as to injection technique and sterility for prevention of possible swelling or infection. Intra-articular injections should not be made through skin that has been recently fired or blistered, or that has excessive scurf and counterirritant on it.

Discard any unused portion of the drug and the empty vial after opening.

Warning

Not to be administered to horses that are to be slaughtered for use in food.

Legend Injection Indications

LEGEND^® Injection is indicated in the treatment of joint dysfunction of the carpus or fetlock in horses due to non-infectious synovitis associated with equine osteoarthritis.

Dosage and Administration

Intravenous - 4 mL (40 mg). Intra-articular - 2 mL (20 mg) in the carpus or fetlock. Treatment may be repeated at weekly intervals for a total of three treatments.

Strict aseptic technique should be observed when administering by intra-articular injection. As with any intra-articular procedure, proper injection site disinfection and animal restraint are important. Excess joint fluid should be aseptically removed prior to injection. Care should be taken to avoid scratching the cartilage surface with the tip of the injection needle. Diffuse swelling lasting 24 to 48 hours may result from movement of the needle while in the joint space.

As with any intra-articular procedure, horses should be given stall rest after treatment before gradually resuming normal activity.

Storage

Store between 4 - 40°C. Protect from sunlight.

How Supplied

LEGEND^® Injection is supplied in cartons containing six 2 mL (20 mg) vials or six 4 mL (40 mg) vials.

REFERENCE:

 ¹ Swanstrom, O.G. 1978. Hyaluronate (hyaluronic acid) and its use, Proc. American Assoc. Equine Pract., 24th annual convention, pp. 345-348.

Legend^® is a registered trademark of Boehringer Ingelheim Vetmedica GmbH, used under license.

Boehringer Ingelheim Animal Health Canada Inc., 5180 South Service Road, Burlington ON L7L 5H4

2050-8693-02

CPN: 1182151.2