Goserelin implant

A 67-year-old man with prostate cancer and an unsuspected pituitary macroadenoma developed a severe frontal headache, nausea and vomiting, and blindness within 12 hours of insertion of a goserelin implant (11). 

Eaton HJ, Phillips PJ, Hanieh A, Cooper J, Bolt J, Torpy DJ. Rapid onset of pituitary apoplexy after goserelin implant for prostate cancer need for heightened awareness. Intern Med J 2()01 31(5) 313 t. 

Goserelin (Zoladex), a hormonal antineoplastic drug used to treat breast cancer, is administered subcutaneously in an unusual way. The drag is contained in a dry pellet that is implanted in the soft tissue of the abdomen, where it is gradually absorbed during a period of 1 to 3 months. After a local anesthetic, such as lido-caine, is administered, a large needle (usually 16 gauge) is used to insert the pellet. 

There are no comparative trials of LHRH agonists, so the choice is usually based on cost (Table 65-1) and on patient and physician preference. Leuprolide acetate is administered daily. Leuprolide depot and goserelin acetate implant can be administered monthly, or every 12 or 16 weeks. 

Dosage forms Zoladex is supplied as a sterile, biodegradable implant containing goserelin acetate equivalent to 3.6mg of... 

Dosage Goserelin (GnRH Analog, Zoladex) Implants... 

Goserelin acetate is available in the form of implantable cylinders, 1-1.5 mm in diameter, that are placed subcutaneously in the upper abdominal area. Goserelin is metabolized in the liver and excreted in the urine. Clearance is greater in women than in men. Stimulation of gonadotropins occurs in the first weeks of therapy, followed by suppression. 

Implants containing 3.6 mg of goserelin are injected subcutaneously every 28 days. 

Implants containing 10.8 mg goserelin are injected subcutaneously every 12 weeks. 

Zoladex implants are indicated for use in the palliative treatment of advanced breast cancer in pre- and peri-menopausal women, in the palliative treatment of advanced carcinoma of the prostate and in the management of endometriosis, including pain relief and the reduction of endometriotic lesions. The implant is fabricated by dispersing goserelin in a PLGA matrix and molding it into a cylindrical shape, which can be injected subcutaneously. 

The release profile of goserelin from the implants has been well characterized during product development. For example, in a study of a Zoladex implant loaded with 10.8 mg of drug, the goserelin present at the surface of the implant was released rapidly, so that mean concentrations increased and reached peak levels within the first 24 hours. The initial release was then followed by a lag period up to 4 days, in which there was a rapid decline in the plasma concentration of the drug. 

In contrast to these microsphere formulations, Zoladex (AstraZeneca) is a small implantable cylinder (approximately 1mm in diameter and 10 mm in length) containing goserelin acetate in a polymer matrix of 50 50 PLG. This system delivers approximately 3.6 mg drug over a 1-month period and is indicated for the treatment of prostate cancer. A second Zoladex system containing 10.6 mg goserelin has also been developed to release the drug for over 3 months. ... 

Fig. 25 Amino acid sequence of goserelin, a biosynthetic analog of gonadotropin-releasing hormone, and the effect of subcutaneous controlled release of goserelin from the biodegradable poly(lactide-glycolide) implant on the serum levels of luteinizing hormone and testosterone.

The Norplant device has been somewhat controversial, however, due to difficulties associated with its removal. A second example of an implantable drug delivery system is Zoladex, which is an implantable biodegradable lactide/glycolide polymeric delivery system for the administration of goserelin acetate. It is available in one-month and three-month presentations and can be injected through a wide-bore needle. 

Zoladex (goserelin acetate injectable implant) Prostate cancer AstraZeneca... 

Zoladex Goserelin acetate PLGA Implant Prostate cancer M Shape... 

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