Ovalia

OVALIA is a yellow colored, round shaped film-coated tablet having both side plain containing 2.5 mg of Letrozole for oral administration.
Each film-coated tablet contains: Letrozole USP 2.5 mg.

Pharmacotherapeutic group: Nonsteroidal aromatase inhibitor.
Pharmacology: Pharmacodynamics: Mechanism of action: By effectively blocking estrogen synthesis, letrozole inhibits the growth or induces the regression of hormone-responsive breast tumors in vivo. Estrogen is implicated as a major risk factor in the majority of breast cancers; therefore, use of the most potent aromatase inhibitor is a logical treatment strategy.
Pharmacokinetics: Absorption: Letrozole is rapidly and completely absorbed from the gastrointestinal tract (mean absolute bioavailability: 99.9%). Food slightly decreases the rate of absorption (median Tmax 1 hour fasted versus 2 hours fed; and mean Cmax 129 ± 20.3 nmol/litre fasted versus 98.7 ± 18.6 nmol/litre fasted) but the extent of absorption (AUC) is not changed. The minor effect on the absorption rate is not considered to be of clinical relevance, and therefore letrozole may be taken without regard to mealtimes.
Distribution: Plasma protein binding of letrozole is approximately 60%, mainly to albumin (55%). The concentration of letrozole in erythrocytes is about 80% of that in plasma. After administration of 2.5 mg 14C-labelled letrozole, approximately 82% of the radioactivity in plasma was unchanged compound. Systemic exposure to metabolites is therefore low. Letrozole is rapidly and extensively distributed to tissues. Its apparent volume of distribution at steady-state is about 1.87 ± 0.47 L/kg.
Biotransformation: Metabolic clearance to a pharmacologically inactive carbinol metabolite is the major elimination pathway of letrozole (CLm = 2.1 L/h) but is relatively slow when compared to hepatic blood flow (about 90 L/h). The cytochrome P450 isoenzymes 3A4 and 2A6 were found to be capable of converting letrozole to this metabolite. In vitro, but their individual contributions to letrozole clearance in vivo have not been established. In an interaction study co-administration with cimetidine, which is known to inhibit only the 3A4 isoenzyme, did not result in a decrease in letrozole clearance suggesting that In vivo the 2A6 isoenzyme plays an important part in total clearance. In this study a slight decrease in AUC and increase in Cmax were observed. Formation of minor unidentified metabolites and direct renal and faecal excretion play only a minor role in the overall elimination of letrozole. Within 2 weeks after administration of 2.5 mg 14C-labelled letrozole to healthy postmenopausal volunteers, 88.2 ± 7.6% of the radioactivity was recovered in urine and 3.8 ± 0.9% in faeces. At least 75% of the radioactivity recovered in urine up to 216 hours (84.7 ± 7.8% of the dose) was attributed to the glucuronide of the carbinol metabolite, about 9% to two unidentified metabolites, and 6% to unchanged letrozole.
Elimination: The apparent terminal elimination half-life in plasma is about 2 to 4 days. After daily administration of 2.5 mg steady-state levels are reached within 2 to 6 weeks. Plasma concentrations at steady-state are approximately 7 times higher than concentrations measured after a single dose of 2.5 mg, while they are 1.5 to 2 times higher than the steady-state values predicted from the concentrations measured after a single dose, indicating a slight non-linearity in the pharmacokinetics of letrozole upon daily administration of 2.5 mg. Since steady-state levels are maintained over time, it can be concluded that no continuous accumulation of letrozole occurs.

Adjuvant treatment of postmenopausal women with hormone receptor positive invasive early breast cancer.
Extended adjuvant treatment of hormone-dependent early invasive breast cancer in postmenopausal women who have received prior standard adjuvant tamoxifen therapy for 5 years.
First-line treatment in postmenopausal women with hormone-dependent advanced breast cancer.
Advanced breast cancer after relapse or disease progression, in women with natural or artificially induced postmenopausal endocrine status, who have previously been treated with anti-oestrogens.
Neoadjuvant treatment of postmenopausal women with hormone receptor positive, HER-2 negative breast cancer where chemotherapy is not suitable and immediate surgery not indicated.
Efficacy has not been demonstrated in patients with hormone receptor negative breast cancer.

Posology: Adult & elderly patients: The recommended dose of Letrozole tablet is 2.5 mg once daily.
In patients with advanced or metastatic breast cancer, treatment with letrozole tablets should continue until tumour progression is evident.
In the adjuvant and extended adjuvant setting, treatment with letrozole tablets should continue for 5 years or until tumour relapse occurs, whichever is first.
In the neoadjuvant setting, treatment with letrozole tablets could be continued for 4 to 8 months in order to establish optimal tumour reduction. If the response is not adequate, treatment with letrozole tablets should be discontinued and surgery scheduled and/or further treatment options discussed with the patient.
Following standard adjuvant tamoxifen therapy, treatment with letrozole tablets should continue for 5 years or until tumour relapse occurs, whichever comes first. In patients with metastatic disease, treatment with letrozole tablets should continue until tumour progression is evident. Regular monitoring to observe progression during the pre-operative treatment period is recommended. No dose adjustment is required for elderly patients.
Paediatric population: Letrozole tablets is not recommended for use in children and adolescents. The safety and efficacy of letrozole tablets in children and adolescents aged up to 17 years have not been established. Limited data are available and no recommendation on a posology can be made.
Renal impairment: No dosage adjustment of letrozole tablets is required for patients with renal insufficiency with creatinine clearance ≥10 ml/min. Insufficient data are available in cases of renal insufficiency with creatinine clearance lower than 10 ml/min.
Hepatic impairment: No dosage adjustment of letrozole tablets is required for patients with mild to moderate hepatic insufficiency (Child-Pugh grade A or B). Insufficient data are available for patients with severe hepatic impairment. Patients with severe hepatic impairment (Child-Pugh C) require close supervision.
Method of administration: Letrozole tablets should be taken orally and can be taken with or without food.
A missed dose should be taken as soon as the patient remembers. However, if it is almost time for the next dose (within 2 or 3 hours), the missed dose should be skipped, and the patient should go back to her regular dosage schedule. Doses should not be doubled because with daily doses over the 2.5 mg recommended dose, over-proportionality in systemic exposure was observed.

There is no clinical experience of overdosage only isolated cases of overdose with letrozole have been reported. In animal studies, letrozole exhibits only a slight degree of acute toxicity. In clinical trials, the highest single and multiple dose tested in healthy volunteers was 30 mg and 5 mg, respectively, the latter also being the highest dose tested in postmenopausal breast cancer patients. Each of these doses was well tolerated. There is no clinical evidence for a particular dose of letrozole resulting in life-threatening symptoms.
There is no specific antidote to letrozole. In general, supportive care, symptomatic treatment and frequent monitoring of vital signs are appropriate.

Hypersensitivity to the active substance or to any of the excipients in the formulation.
Premenopausal endocrine status.
Premenopausal, pregnant or lactating women

Menopausal status: In patients whose menopausal status is unclear, luteinising hormone (LH), follicle-stimulating hormone (FSH) and/or oestradiol levels should be measured before initiating treatment with letrozole. Only women of postmenopausal endocrine status should receive letrozole.
Bone effects: Letrozole is a potent oestrogen-lowering agent. Women with a history of osteoporosis and/or fractures, or who are at increased risk of osteoporosis, should have their bone mineral density formally assessed prior to the commencement of adjuvant and extended adjuvant treatment and monitored during and following treatment with letrozole. Treatment or prophylaxis for osteoporosis should be initiated as appropriate and carefully monitored. In the adjuvant setting a sequential treatment schedule (letrozole 2 years followed by tamoxifen 3 years) could also be considered depending on the patient's safety profiles.
Tendonitis and tendon rupture: Tendonitis and tendon ruptures (rare) may occur. Close monitoring of the patients and appropriate measures (e.g. immobilisation) must be initiated for the affected tendon.
Other warnings: Co-administration of letrozole with tamoxifen, other anti-oestrogens or oestrogen-containing therapies should be avoided as these substances may diminish the pharmacological action of letrozole.
Lactose: Patients with rare hereditary problems of galactose intolerance, total lactase deficiency or glucose-galactose malabsorption should not take this medicine.
Sodium: This medicine contains less than 1 mmol sodium (23 mg) per tablet, that is to say essentially 'sodium-free'.
Renal impairment: Letrozole has not been investigated in a sufficient number of patients with a creatinine clearance lower than 10 ml/min. The potential risk/benefit to such patients should be carefully considered before administration of letrozole.
Hepatic impairment: In patients with severe hepatic impairment (Child-Pugh C), systemic exposure and terminal half-life were approximately doubled compared to healthy volunteers. Such patients should therefore be kept under close supervision.

Women of perimenopausal status or child-bearing potential: Letrozole should only be used in women with a clearly established postmenopausal status. As there are reports of women regaining ovarian function during treatment with letrozole despite a clear postmenopausal status at start of therapy, the physician needs to discuss adequate contraception when necessary.
Pregnancy: Based on human experience in which there have been isolated cases of birth defects (labial fusion, ambiguous genitalia), letrozole may cause congenital malformations when administered during pregnancy. Studies in animals have shown reproductive toxicity.
Letrozole is contraindicated during pregnancy.
Lactation: It is unknown whether letrozole and its metabolites are excreted in human milk. A risk to the newborns/infants cannot be excluded.
Letrozole is contraindicated during breast-feeding.
Fertility: The pharmacological action of letrozole is to reduce oestrogen production by aromatase inhibition. In premenopausal women, the inhibition of oestrogen synthesis leads to feedback increases in gonadotropin (LH, FSH) levels. Increased FSH levels in tum stimulate follicular growth and can induce ovulation.

The frequencies of adverse reactions for letrozole are mainly based on data collected from clinical trials.
Up to approximately one third of the patients treated with letrozole in the metastatic settings and approximately 80% of the patients in the adjuvant setting as well as in the extended adjuvant setting experienced adverse reactions. The majority of the adverse reactions occurred during the first few weeks of treatment.
The most frequently reported adverse reactions in clinical studies were hot flushes, hypercholesterolaemia, arthralgia, fatigue, increased sweating and nausea.
Important additional adverse reactions that may occur with letrozole are skeletal events such as osteoporosis and/or bone fractures and cardiovascular events.

Metabolism of letrozole is partly mediated via CYP2A6 and CYP3A4. Clinical interaction studies with cimetidine and warfarin indicated that the co-administration of letrozole with these drugs does not result in clinically significant drug interactions, even though cimetidine is a known weak inhibitor of one of the cytochrome P450 isoenzymes capable of metabolising letrozole in vitro.
There was no evidence of other clinically relevant interaction in patients receiving other commonly prescribed drugs (e.g. benzodiazepines; barbiturates; NSAIDs such as diclofenac sodium, ibuprofen; paracetamol; furosemide; omeprazole).
There is no clinical experience to date on the use of letrozole in combination with oestrogens or other anticancer agents, other than tamoxifen. Tamoxifen, other anti-oestrogens or oestrogen-containing therapies may diminish the pharmacological action of letrozole. In addition, co-administration of tamoxifen with letrozole has been shown to substantially decrease plasma concentrations of letrozole. Co-administration of letrozole with tamoxifen, other anti-oestrogens or oestrogens should be avoided.
Letrozole inhibits in vitro the cytochrome P450 isoenzymes 2A6 and moderately 2C19, however, CYP2A6 does not play a major role in drug metabolism. In in vitro experiments, letrozole was not able to substantially inhibit the metabolism of diazepam (a substrate of CYP2C19) at concentrations approximately 100-fold higher than those observed in plasma at steady-state. Thus, clinically relevant interactions with CYP2C19 are unlikely to occur. Nevertheless, caution should be used in the concomitant administration of drugs whose disposition is mainly dependent on these isoenzymes and whose therapeutic index is narrow (e.g phenytoin, clopidogrel).

Store at temperatures not exceeding 30°C.
Special Precautions for Storage: This medicinal product does not require any special storage conditions.

Cancer Hormone Therapy

L02BG04 - letrozole ; Belongs to the class of enzyme inhibitors. Used in treatment of neoplastic diseases.

Rx