Goserelin 3.6mg Depot 1s – AZ
ZOLADEX® (goserelin acetate implant), contains a potent synthetic decapeptide analog of luteinizing hormone-releasing hormone (LHRH), also known as a gonadotropin-releasing hormone (GnRH) agonist analog. Goserelin acetate is chemically described as an acetate salt of [D-Ser(But)6, Azgly10]LHRH. Its chemical structure is pyro-Glu-His-Trp-Ser-Tyr-D-Ser(But)-Leu-Arg-Pro-Azgly-NH2 acetate [C59H84N18O14 • (C2H4O2)x where x = 1 to 2.4].
Goserelin acetate is an off-white powder with a molecular weight of 1269 Daltons (free base). It is freely soluble in glacial acetic acid. It is soluble in water, 0.1M hydrochloric acid, 0.1M sodium hydroxide, dimethylformamide, and dimethyl sulfoxide. Goserelin acetate is practically insoluble in acetone, chloroform, and ether.
ZOLADEX 10.8 mg (goserelin acetate implant) implant is supplied as a sterile, biodegradable product containing goserelin acetate equivalent to 10.8 mg of goserelin. ZOLADEX is designed for subcutaneous implantation with the continuous release over a 12-week period. Goserelin acetate is dispersed in a matrix of D, L-lactic and glycolic acids copolymer (12.82-14.76 mg/dose) containing less than 2% acetic acid and up to 10% goserelin-related substances and presented as a sterile, white to cream-colored 1.5 mm diameter cylinder, preloaded in a special single-use syringe with a 14-gauge x 36 +/- 0.5 mm siliconized needle with protective needle sleeve (SafeSystem™ Syringe) in a sealed, light- and moisture-proof, aluminum foil laminate pouch containing a desiccant capsule.
Studies of the D, L-lactic and glycolic acids copolymer have indicated that it is completely biodegradable and has no demonstrable antigenic potential.
ZOLADEX is also supplied as a sterile, biodegradable product containing goserelin acetate equivalent to 3.6 mg of goserelin designed for administration every 28 days.
Stage B2-C Prostatic Carcinoma
ZOLADEX is indicated for use in combination with flutamide for the management of locally confined Stage T2b-T4 (Stage B2-C) carcinoma of the prostate. Treatment with ZOLADEX and flutamide should start 8 weeks prior to initiating radiation therapy and continue during radiation therapy [see DOSAGE AND ADMINISTRATION and Clinical Studies].
ZOLADEX is indicated in the palliative treatment of advanced carcinoma of the prostate [see DOSAGE AND ADMINISTRATION and Clinical Studies].
ZOLADEX is indicated for the management of endometriosis, including pain relief and reduction of endometriotic lesions for the duration of therapy. Experience with ZOLADEX for the management of endometriosis has been limited to women 18 years of age and older treated for 6 months [see DOSAGE AND ADMINISTRATION and Clinical Studies].
ZOLADEX is indicated for use as an endometrial-thinning agent prior to endometrial ablation for dysfunctional uterine bleeding [see DOSAGE AND ADMINISTRATION and Clinical Studies].
Advanced Breast Cancer
ZOLADEX is indicated for use in the palliative treatment of advanced breast cancer in pre- and perimenopausal women.
The estrogen and progesterone receptor values may help to predict whether ZOLADEX therapy is likely to be beneficial [see DOSAGE AND ADMINISTRATION, CLINICAL PHARMACOLOGY, and Clinical Studies].
The automatic safety feature of the syringe aids in the prevention of needlestick injury.
DOSAGE AND ADMINISTRATION
ZOLADEX, at a dose of 3.6 mg, should be administered subcutaneously every 28 days into the anterior abdominal wall below the navel line using an aseptic technique under the supervision of a physician.
While a delay of a few days is permissible, every effort should be made to adhere to the 28-day schedule.
Stage B2-C Prostatic Carcinoma
When ZOLADEX is given in combination with radiotherapy and flutamide for patients with Stage T2b-T4 (Stage B2-C) prostatic carcinoma, treatment should be started 8 weeks prior to initiating radiotherapy and should continue during radiation therapy. A treatment regimen using a ZOLADEX 3.6 mg depot 8 weeks before radiotherapy, followed in 28 days by the ZOLADEX 10.8 mg depot, can be administered. Alternatively, four injections of 3.6 mg depot can be administered at 28-day intervals, two depots preceding and two during radiotherapy.
For the management of advanced prostate cancer, ZOLADEX is intended for long-term administration unless clinically inappropriate.
For the management of endometriosis, the recommended duration of administration is 6 months.
Currently, there are no clinical data on the effect of treatment of benign gynecological conditions with ZOLADEX for periods in excess of 6 months.
Retreatment cannot be recommended for the management of endometriosis since safety data for retreatment are not available. If the symptoms of endometriosis recur after a course of therapy, and further treatment with ZOLADEX is contemplated, consideration should be given to monitoring bone mineral density. Clinical studies suggest the addition of Hormone Replacement Therapy (estrogens and/or progestins) to ZOLADEX is effective in reducing bone mineral loss which occurs with ZOLADEX alone without compromising the efficacy of ZOLADEX in relieving the symptoms of endometriosis. The addition of Hormone Replacement Therapy may also reduce the occurrence of vasomotor symptoms and vaginal dryness associated with hypoestrogenism. The optimal drugs, dose, and duration of treatment have not been established.
For use as an endometrial-thinning agent prior to endometrial ablation, the dosing recommendation is one or two depots (with each depot given four weeks apart). When one depot is administered, surgery should be performed at four weeks. When two depots are administered, surgery should be performed within two to four weeks following administration of the second depot.
For the management of advanced breast cancer, ZOLADEX is intended for long-term administration unless clinically inappropriate.
Renal Or Hepatic Impairment
No dosage adjustment is necessary for patients with renal or hepatic impairment.
The proper method of administration of ZOLADEX is described in the instructions that follow.
1. Put the patient in a comfortable position with the upper part of the body slightly raised. Prepare an area of the anterior abdominal wall below the navel line with an alcohol swab.
NOTE: Caution should be taken while injecting ZOLADEX into the anterior abdominal wall due to the proximity of the underlying inferior epigastric artery and its branches.
Examine the foil pouch and syringe for damage. Remove the syringe from the opened foil pouch and hold the syringe at a slight angle to the light. Check that at least part of the ZOLADEX implant is visible.
2. Grasp the red plastic safety tab and pull away from the syringe, and discard. Remove needle cover. Unlike liquid injections, there is no need to remove air bubbles as attempts to do so may displace the ZOLADEX implant.
Holding the syringe around the protective sleeve, using an aseptic technique, pinch the skin of the patient’s anterior abdominal wall below the navel line. With the bevel of the needle facing up, insert the needle at a 30 to 45-degree angle to the skin in one continuous deliberate motion until the protective sleeve touches the patient’s skin.
NOTE: The ZOLADEX syringe cannot be used for aspiration. If the hypodermic needle penetrates a large vessel, blood will be seen instantly in the syringe chamber. If a vessel is penetrated, withdraw the needle and inject it with a new syringe elsewhere. Monitor patients for signs or symptoms of abdominal hemorrhage. Use extra care when administering ZOLADEX to patients with a low BMI and/or to patients receiving full-dose anticoagulation [see WARNINGS AND PRECAUTIONS].
3. Do not penetrate into muscle or peritoneum.
4. To administer the ZOLADEX implant and to activate the protective sleeve, grasp the barrel at the finger grip and depress the plunger until you cannot depress it any further. If the plunger is not depressed fully, the protective sleeve will NOT activate. When the protective sleeve ‘clicks’, the protective sleeve will automatically begin to slide to cover the needle.
NOTE: The needle does not retract.
5. Withdraw the needle and allow the protective sleeve to slide and cover the needle. Dispose of the syringe in an approved sharps collector.
NOTE: In the unlikely event of the need to surgically remove ZOLADEX, it may be localized by ultrasound.
Dosage Forms And Strengths
ZOLADEX is supplied as a sterile and totally biodegradable D, L-lactic and glycolic acids copolymer (13.3-14.3 mg/dose) impregnated with goserelin acetate equivalent to 3.6 mg of goserelin in a disposable syringe device fitted with a 16-gauge x 36 +/- 0.5 mm siliconized hypodermic needle with protective needle sleeve [SafeSystem™ Syringe] (NDC 0310-095036).
Storage And Handling
ZOLADEX is supplied as a sterile and totally biodegradable D, L-lactic and glycolic acids copolymer (13.3-14.3 mg/dose) impregnated with goserelin acetate equivalent to 3.6 mg of goserelin in a disposable syringe device fitted with a 16-gauge x 36 +/- 0.5 mm siliconized hypodermic needle with protective needle sleeve [SafeSystem™ Syringe] (NDC 0310-095036). The unit is sterile and comes in a sealed, light- and moisture-proof, aluminum foil laminate pouch containing a desiccant capsule. Store at room temperature (do not exceed 25°C [77°F]).
Stage B2-C Prostatic Carcinoma
Treatment with ZOLADEX and flutamide did not add substantially to the toxicity of radiation treatment alone. The following adverse experiences were reported during a multicenter clinical trial comparing ZOLADEX + flutamide + radiation versus radiation alone. The most frequently reported (greater than 5%) adverse experiences are listed below:
Table 1: ADVERSE EVENTS DURING ACUTE RADIATION THERAPY (within first 90 days of radiation therapy)
flutamide + ZOLADEX + Radiation
Table 2: ADVERSE EVENTS DURING LATE RADIATION PHASE (after 90 days of radiation therapy)
flutamide + ZOLADEX + Radiation
ZOLADEX has been found to be generally well-tolerated in clinical trials. Adverse reactions reported in these trials were rarely severe enough to result in the patients’ withdrawal from ZOLADEX treatment. As seen with other hormonal therapies, the most commonly observed adverse events during ZOLADEX therapy were due to the expected physiological effects from decreased testosterone levels. These included hot flashes, sexual dysfunction, and decreased erections.
Tumor Flare Phenomenon
Initially, ZOLADEX, like other GnRH agonists, causes transient increases in serum levels of testosterone. A small percentage of patients experienced a temporary worsening of signs and symptoms, usually manifested by an increase in cancer-related pain which was managed symptomatically. Isolated cases of exacerbation of disease symptoms, either ureteral obstruction or spinal cord compression, occurred at similar rates in controlled clinical trials with both ZOLADEX and orchiectomy. The relationship of these events to therapy is uncertain [see WARNINGS AND PRECAUTIONS].
In the controlled clinical trials of ZOLADEX versus orchiectomy, the following events were reported as adverse reactions in greater than 5% of the patients.
No formal drug-drug interaction studies have been performed. No confirmed interactions have been reported between ZOLADEX and other drugs.
Drug/Laboratory Test Interactions
Administration of ZOLADEX in therapeutic doses results in suppression of the pituitary-gonadal system. Because of this suppression, diagnostic tests of pituitary-gonadotropic and gonadal functions conducted during treatment and until the resumption of menses may show results which are misleading. Normal function is usually restored within 12 weeks after treatment is discontinued.
Women Of Childbearing Potential And Pregnancy
Before starting treatment with ZOLADEX, pregnancy must be excluded for women using ZOLADEX for benign gynecological conditions. Women of childbearing potential should be advised to avoid becoming pregnant.
Effective nonhormonal contraception must be used by all premenopausal women during ZOLADEX therapy and for 12 weeks following discontinuation of therapy. When used every 28 days, ZOLADEX usually inhibits ovulation and stops menstruation; however, pregnancy prevention is not ensured. Effects on reproductive function are expected to occur with chronic administration as a result of the anti-gonadotrophic properties of the drug.
Based on the mechanism of action in humans and findings of increased pregnancy loss in animal studies, ZOLADEX can cause fetal harm when administered to a pregnant woman. If this drug is used during pregnancy for the palliative treatment of breast cancer, then the patient should be apprised of the potential hazard to the fetus [see Use in Specific Populations].
Tumor Flare Phenomenon
Initially, ZOLADEX, like other GnRH agonists, causes transient increases in serum levels of testosterone in men with prostate cancer, and estrogen in women with breast cancer. Transient worsening of symptoms, or the occurrence of additional signs and symptoms of prostate or breast cancer, may occasionally develop during the first few weeks of ZOLADEX treatment. A small number of patients may experience a temporary increase in bone pain, which can be managed symptomatically.
As with other GnRH agonists, isolated cases of ureteral obstruction and spinal cord compression have been observed in patients with prostate cancer. If spinal cord compression or renal impairment secondary to ureteral obstruction develops, the standard treatment of these complications should be instituted. For extreme cases in prostate cancer patients, an immediate orchiectomy should be considered.
Hyperglycemia And Diabetes
Hyperglycemia and an increased risk of developing diabetes have been reported in men receiving GnRH agonists. Hyperglycemia may represent development of diabetes mellitus or worsen glycemic control in patients with diabetes. Monitor blood glucose and/or glycosylated hemoglobin (HbA1c) periodically in patients receiving a GnRH agonist and manage with current practice for the treatment of hyperglycemia or diabetes [see PATIENT INFORMATION].
Increased risk of developing myocardial infarction, sudden cardiac death and stroke have been reported in association with the use of GnRH agonists in men. The risk appears low based on the reported odds ratios and should be evaluated carefully along with cardiovascular risk factors when determining a treatment for patients with prostate cancer. Patients receiving a GnRH agonist should be monitored for symptoms and signs suggestive of the development of cardiovascular disease and be managed according to current clinical practice [see PATIENT INFORMATION].
As with other GnRH agonists or hormonal therapies (antiestrogens, estrogens, etc.), hypercalcemia has been reported in some prostate and breast cancer patients with bone metastases after starting treatment with ZOLADEX. If hypercalcemia does occur, appropriate treatment measures should be initiated.
Hypersensitivity, antibody formation, and acute anaphylactic reactions have been reported with GnRH agonist analogs [see CONTRAINDICATIONS].
Of 115 women worldwide treated with ZOLADEX and tested for development of binding to goserelin following treatment with ZOLADEX, one patient showed low-titer binding to goserelin. On further testing of this patient’s plasma obtained following treatment, her goserelin binding component was found not to be precipitated with rabbit antihuman immunoglobulin polyvalent sera. These findings suggest the possibility of antibody formation.
The pharmacologic action of ZOLADEX on the uterus and cervix may cause an increase in cervical resistance. Therefore, care should be taken when dilating the cervix for endometrial ablation.
Effect On QT/QTc Interval
Androgen deprivation therapy may prolong the QT/QTc interval. Providers should consider whether the benefits of androgen deprivation therapy outweigh the potential risks in patients with congenital long QT syndrome, congestive heart failure, frequent electrolyte abnormalities, and in patients taking drugs known to prolong the QT interval. Electrolyte abnormalities should be corrected. Consider periodic monitoring of electrocardiograms and electrolytes.
Injection Site Injury
Injection site injury and vascular injury including pain, hematoma, hemorrhage and hemorrhagic shock, requiring blood transfusions and surgical intervention, have been reported with ZOLADEX. Extra care should be taken when administering ZOLADEX to patients with low BMI and/or to patients receiving full-dose anticoagulation [see DOSAGE AND ADMINISTRATION and PATIENT INFORMATION].
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Subcutaneous implantation of goserelin in male and female rats once every 4 weeks for 1 year and recovery for 23 weeks at doses of about 80 and 150 mcg/kg (males) and 50 and 100 mcg/kg (females) daily resulted in an increased incidence of pituitary adenomas. An increased incidence of pituitary adenomas was also observed following the subcutaneous implant of goserelin in rats at similar dose levels for a period of 72 weeks in males and 101 weeks in females. The relevance of the rat pituitary adenomas to humans has not been established. Subcutaneous implants of goserelin every 3 weeks for 2 years delivered to mice at doses of up to 2400 mcg/kg/day resulted in an increased incidence of histiocytic sarcoma of the vertebral column and femur. Human dose/exposure multiples could not be calculated from available animal data.
Mutagenicity tests using bacterial and mammalian systems for point mutations and cytogenetic effects have provided no evidence for mutagenic potential.
The administration of goserelin led to changes that were consistent with gonadal suppression in both male and female rats as a result of its endocrine action. In male rats administered 500-1000 mcg/kg/day, a decrease in weight and atrophic histological changes were observed in the testes, epididymis, seminal vesicle and prostate gland with complete suppression of spermatogenesis. In female rats administered 50-1000 mcg/kg/day, suppression of ovarian function led to decreased size and weight of ovaries and secondary sex organs; follicular development was arrested at the antral stage and the corpora lutea were reduced in size and number. Except for the testes, an almost complete histologic reversal of these effects in males and females was observed several weeks after dosing was stopped; however, fertility and general reproductive performance were reduced in those that became pregnant after goserelin was discontinued. Fertile matings occurred within 2 weeks after cessation of dosing, even though total recovery of reproductive function may not have occurred before mating took place; and, the ovulation rate, the corresponding implantation rate, and the number of live fetuses were reduced.
Based on histological examination, drug effects on reproductive organs were reversible in male and female dogs administered 107-214 mcg/kg/day goserelin when drug treatment was stopped after continuous administration for 1 year. Human dose/exposure multiples could not be calculated from available animal data.