There is no data on removal or dissolution of the implant.
There is an increased risk of incident depression (which may be severe) in patients undergoing treatment with GnRH agonists, such as Goserelin. Patients should be informed accordingly and treated as appropriate if symptoms occur. Carefully monitor patients with known depression or history of depression.
Androgen deprivation therapy may prolong the QT interval.
In patients with a history of or risk factors for QT prolongation and in patients receiving concomitant medicinal products that might prolong the QT interval (see section 4.5) physicians should assess the benefit risk ratio including the potential for Torsade de pointes prior to initiating Zoladex LA.
Injection site injury has been reported with Zoladex LA, including events of pain, haematoma, haemorrhage and vascular injury. Monitor affected patients for signs or symptoms of abdominal haemorrhage. In very rare cases, administration error resulted in vascular injury and haemorrhagic shock requiring blood transfusions and surgical intervention. Extra care should be taken when administering Zoladex LA to patients with a low BMI and/or receiving full anticoagulation medications (see section 4.2).
Treatment with Zoladex LA may lead to positive reactions in anti-doping tests.
Patients with hypertension should be monitored carefully, as should patients with risk factors for diabetes with treatment initiated, if appropriate, according to national guidelines.
Males
The use of Zoladex in men at particular risk of developing ureteric obstruction or spinal cord compression should be considered carefully, and the patients monitored closely during the first month of therapy. If spinal cord compression or renal impairment due to ureteric obstruction are present or develop, specific standard treatment of these complications should be instituted.
Consideration should be given to the initial use of an anti-androgen (e.g. cyproterone acetate 300 mg daily for three days before, and three weeks after commencement of Zoladex) at the start of LHRH analogue therapy since this has been reported to prevent the possible sequelae of the initial rise in serum testosterone.
The use of LHRH agonists may cause reduction in bone mineral density. In men, preliminary data suggest that the use of a bisphosphonate in combination with an LHRH agonist may reduce bone mineral loss. Particular caution is necessary in patients with additional risk factors for osteoporosis (e.g. chronic alcohol abusers, smokers, long-term therapy with anticonvulsants or corticosteroids, family history of osteoporosis).
Myocardial infarction and cardiac failure were observed in a pharmaco-epidemiology study of LHRH agonists used in the treatment of prostate cancer. The risk appears to be increased when used in combination with anti-androgens.
Reduction in glucose tolerance has been observed in men receiving LHRH agonists. This may manifest as diabetes or loss of glycaemic control in patients with pre-existing diabetes mellitus. Thus, monitoring of blood glucose levels should be considered.
Females
Breast Cancer:
Following commencement of goserelin in pre- and peri-menopausal women adequate ovarian suppression should be confirmed before initiating aromatase inhibitor therapy (see section 4.2).
Reduced bone mineral density:
The use of LHRH agonists may cause reduction in bone mineral density. Following two years treatment for early breast cancer, the average loss of bone mineral density was 6.2% and 11.5% at the femoral neck and lumbar spine respectively. This loss has been shown to be partially reversible at the one year off treatment follow-up with recovery to 3.4% and 6.4% relative to baseline at the femoral neck and lumbar spine respectively, although this recovery is based on very limited data. In the majority of women, currently available data suggest that recovery of bone loss occurs after cessation of therapy.
Preliminary data suggest that the use of Zoladex in combination with tamoxifen in patients with breast cancer may reduce bone mineral loss.
Tumour flare:
Initially, breast cancer patients may experience a temporary increase in signs and symptoms, which can be managed symptomatically.
Hypercalcemia:
Rarely, breast cancer patients with metastases have developed hypercalcaemia on initiation of therapy. In the presence of symptoms indicative of hypercalcaemia (e.g. thirst), hypercalcaemia should be excluded.
Withdrawal bleeding
During early treatment with Zoladex some women may experience vaginal bleeding of variable duration and intensity. If vaginal bleeding occurs it is usually in the first month after starting treatment. Such bleeding probably represents oestrogen withdrawal bleeding and is expected to stop spontaneously. If bleeding continues, the reason should be investigated.
Fertile women should use non-hormonal contraceptive methods during treatment with Zoladex and until reset of menstruation following discontinuation of treatment with Zoladex.
Rarely, some women may enter the menopause during treatment with LHRH analogues and not resume menses on cessation of therapy. Whether this is an effect of Zoladex treatment or a reflection of their gynaecological condition is not known.
Paediatric population
Zoladex LA is not indicated for use in children, as safety and efficacy have not been established in this patient group.