Viadur® (leuprolide acetate implant) is a sterile nonbiodegradable, osmotically
driven miniaturized implant designed to deliver leuprolide acetate for 12 months
at a controlled rate (Figure A). Viadur® (leuprolide acetate implant) incorporates DUROS® technology.
The system contains 65 mg of leuprolide (free base). Leuprolide acetate is a
synthetic nonapeptide analog of naturally occurring gonadotropin-releasing hormone
(GnRH or LH-RH). The analog possesses greater potency than the natural hormone.
The implant is inserted subcutaneously in the inner aspect of the upper arm.
After 12 months, the implant must be removed. At the time an implant is removed,
another implant may be inserted to continue therapy.
Viadur® contains 72 mg of leuprolide acetate (equivalent to 65 mg leuprolide
free base) dissolved in 104 mg dimethyl sulfoxide. The 4 mm by 45 mm titanium
alloy reservoir houses a polyurethane rate-controlling membrane, an elastomeric
piston, and a polyethylene diffusion moderator. The reservoir also contains
the osmotic tablets, which are not released with the drug formulation. The osmotic
tablets are composed of sodium chloride, sodium carboxymethyl cellulose, povidone,
magnesium stearate, and sterile water for injection. Polyethylene glycol fills
the space between the osmotic tablets and the reservoir. A minute amount of
silicone medical fluid is used during manufacture as a lubricant. The weight
of the implant is approximately 1.1g.
Figure A : Viadur® (leuprolide acetate implant) (diagram
not to scale)
The chemical name is 5-Oxo-L-prolyl-L-histidyl-L-tryptophyl-L-seryl-L-tyrosyl-D-leucyl-Lleucyl-L-arginyl-N-ethyl-L-prolinamide
acetate (salt), with the following structural formula:
Last reviewed on RxList: 3/8/2011
This monograph has been modified to include the generic and brand name in many instances.