Legend Injectable Solution
Bayer Legend Injectable Solution is indicated
in the treatment of joint dysfunction of the carpus or fetlock in horses due to
non-infectious synovitis associated with equine osteoarthritis.
Legend Injection Solution is a
clear, colorless solution of low viscosity. Legend Injectable Solution is
pyrogen free, sterile and does not contain a preservative. It is administered by
intravenous or intra-articular injection only.
Hyaluronic acid, the conjugate acid of hyaluronate sodium, is extracted from the
capsule of Streptococcus spp. and purified, resulting in a form which is
essentially free of protein and nucleic acids.
Legend Injectable Solution is supplied in 2 ml (20 mg) and 4 ml (40 mg) vials.
Each ml contains 10 mg hyaluronate sodium, 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.
Hyaluronic acid, a glycosaminoglycan, 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
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 microorganisms.
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.
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.
There are no known contraindications for the use of
Legend (hyaluronate sodium) Injectable Solution in horses.
Legend Injectable Solution 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 Injectable Solution 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 Reactions:
No local or systemic side effects were
observed in the clinical field trials with either intravenous or intra-articular
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 the 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
Not for use in horses intended for food.
Safety in breeding animals has not been determined with Legend Injectable
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
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
For intravenous administration, use aseptic technique and inject slowly into the
Horses should be given stall rest after treatment before gradually resuming
Discard any unused portion of the drug and the empty vial after opening.
Federal law restricts this drug to use by or on the order of a
Packaging: Legend Injectable Solution 10mg/ml, 4 ml Vial
Rx Medication Sold Only To Licensed Veterinarians & Pharmacies. Current License Must Be On File Prior To Shipping.