Secondary hyperparathyroidism

Adults

Treatment of secondary hyperparathyroidism (HPT) in patients with end-stage renal disease (ESRD) on maintenance dialysis therapy.

Cinacalcet may be used as part of a therapeutic regimen including phosphate binders and/or Vitamin D sterols, as appropriate (see section 5.1).

Parathyroid carcinoma and primary hyperparathyroidism in adults

Reduction of hypercalcaemia in adult patients with:

• parathyroid carcinoma.

• primary HPT for whom parathyroidectomy would be indicated on the basis of serum calcium levels (as defined by relevant treatment guidelines), but in whom parathyroidectomy is not clinically appropriate or is contraindicated.

Posology

Secondary hyperparathyroidism

Adults and elderly (> 65 years)

The recommended starting dose for adults is 30 mg once per day. Cinacalcet should be titrated every 2 to 4 weeks to a maximum dose of 180 mg once daily to achieve a target parathyroid hormone (PTH) in dialysis patients of between 150-300 pg/mL (15.9-31.8 pmol/L) in the intact PTH (iPTH) assay. PTH levels should be assessed at least 12 hours after dosing with Cinacalcet. Reference should be made to current treatment guidelines.

PTH should be measured 1 to 4 weeks after initiation or dose adjustment of Cinacalcet. PTH should be monitored approximately every 1-3 months during maintenance. Either the intact PTH (iPTH) or bio-intact PTH (biPTH) may be used to measure PTH levels; treatment with cinacalcet does not alter the relationship between iPTH and biPTH.

Dose adjustment based on serum calcium levels

Corrected serum calcium should be measured and monitored and should be at or above the lower limit of the normal range prior to administration of first dose of cinacalcet (see section 4.4). The normal calcium range may differ depending on the methods used by your local laboratory.

During dose titration, serum calcium levels should be monitored frequently and within 1 week of initiation or dose adjustment of Cinacalcet. Once the maintenance dose has been established, serum calcium should be measured approximately monthly. In the event that corrected serum calcium levels fall below 8.4 mg/dl (2.1 mmol/L) and/or symptoms of hypocalcemia occur the following management is recommended:

Paediatric population

Cinacalcet is not indicated for use in children and adolescents.

Parathyroid carcinoma and primary hyperparathyroidism

Adults and elderly (> 65 years)

The recommended starting dose of cinacalcet for adults is 30 mg twice per day. The dose of cinacalcet should be titrated every 2 to 4 weeks through sequential doses of 30 mg twice daily, 60 mg twice daily, 90 mg twice daily, and 90 mg three or four times daily as necessary to reduce serum calcium concentration to or below the upper limit of normal. The maximum dose used in clinical trials was 90 mg four times daily.

Serum calcium should be measured within 1 week after initiation or dose adjustment of cinacalcet. Once maintenance dose levels have been established, serum calcium should be measured every 2 to 3 months. After titration to the maximum dose of cinacalcet, serum calcium should be periodically monitored; if clinically relevant reductions in serum calcium are not maintained, discontinuation of cinacalcet therapy should be considered (see section 5.1).

Paediatric population

The safety and efficacy of cinacalcet in children for the treatment of parathyroid carcinoma and primary hyperparathyroidism have not been established. No data are available.

Hepatic impairment

No change in starting dose is necessary. Cinacalcet should be used with caution in patients with moderate to severe hepatic impairment and treatment should be closely monitored during dose titration and continued treatment (see sections 4.4 and 5.2).

Method of administration

For oral use.

Tablets should be taken whole and should not be chewed, crushed or divided.

It is recommended that Cinacalcet be taken with food or shortly after a meal, as studies have shown that bioavailability of cinacalcet is increased when taken with food (see section 5.2).

Hypersensitivity to the active substance or to any of the excipients listed in section 6.1.

Hypocalcaemia (see sections 4.2 and 4.4).

Serum calcium

Life threatening events and fatal outcomes associated with hypocalcaemia have been reported in adult and paediatric patients treated with cinacalcet. Manifestations of hypocalcaemia may include paraesthesias, myalgias, cramping, tetany and convulsions. Decreases in serum calcium can also prolong the QT interval, potentially resulting in ventricular arrhythmia secondary to hypocalcaemia. Cases of QT prolongation and ventricular arrhythmia have been reported in patients treated with cinacalcet (see section 4.8). Caution is advised in patients with other risk factors for QT prolongation such as patients with known congenital long QT syndrome or patients receiving medicinal products known to cause QT prolongation.

Since cinacalcet lowers serum calcium, patients should be monitored carefully for the occurrence of hypocalcaemia (see section 4.2). Serum calcium should be measured within 1 week after initiation or dose adjustment of Cinacalcet.

Adults

Cinacalcet treatment should not be initiated in patients with a serum calcium (corrected for albumin) below the lower limit of the normal range.

In CKD patients receiving dialysis who were administered cinacalcet, approximately 30% of patients had at least one serum calcium value less than 7.5 mg/dL (1.9 mmol/L).

CKD patients not on dialysis

Cinacalcet is not indicated for CKD patients not on dialysis. Investigational studies have shown that CKD patients not on dialysis treated with cinacalcet have an increased risk for hypocalcaemia (serum calcium levels < 8.4 mg/dL [2.1 mmol/L]) compared with cinacalcet-treated CKD patients on dialysis, which may be due to lower baseline calcium levels and/or the presence of residual kidney function.

Seizures

Cases of seizures have been reported in patients treated with cinacalcet (see section 4.8). The threshold for seizures is lowered by significant reductions in serum calcium level. Therefore, serum calcium levels should be closely monitored in patients receiving cinacalcet, particulaly in patients with a history of a seizure disorder.

Hypotension and/or worsening heart failure

Cases of hypotension and/or worsening heart failure have been reported in patients with impaired cardiac function, in which a causal relationship to cinacalcet could not be completely excluded and may be mediated by reductions in serum calcium levels (see section 4.8).

Co-administration with other medicinal products

Administer cinacalcet with caution in patients receiving any other medicinal products known to lower serum calcium. Closely monitor serum calcium (see section 4.5).

Patients receiving cinacalcet should not be given etelcalcetide. Concurrent administration may result in severe hypocalcaemia.

General

Adynamic bone disease may develop if PTH levels are chronically suppressed below approximately 1.5 times the upper limit of normal with the iPTH assay. If PTH levels decrease below the recommended target range in patients treated with Cinacalcet, the dose of Cinacalcet and/or vitamin D sterols should be reduced or therapy discontinued.

Testosterone levels

Testosterone levels are often below the normal range in patients with end-stage renal disease. In a clinical study of ESRD patients on dialysis, free testosterone levels decreased by a median of 31.3% in the cinacalcet-treated patients and by 16.3% in the placebo-treated patients after 6 months of treatment. An open-label extension of this study showed no further reductions in free and total testosterone concentrations over a period of 3 years in cinacalcet-treated patients. The clinical significance of these reductions in serum testosterone is unknown.

Hepatic impairment

Due to the potential for 2 to 4 fold higher plasma levels of cinacalcet in patients with moderate to severe hepatic impairment (Child-Pugh classification), Cinacalcet should be used with caution in these patients and treatment should be closely monitored (see sections 4.2 and 5.2).

Lactose

Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take this medicine.

Medicinal products known to reduce serum calcium

Concurrent administration of other medicinal products known to reduce serum calcium and cinacalcet may result in an increased risk of hypocalcaemia (see section 4.4). Patients receiving cinacalcet should not be given etelcalcetide (see section 4.4).

Effect of other medications on cinacalcet

Cinacalcet is metabolised in part by the enzyme CYP3A4. Co-administration of 200 mg bid ketoconazole, a strong inhibitor of CYP3A4, caused an approximate 2-fold increase in cinacalcet levels. Dose adjustment of Cinacalcet may be required if a patient receiving Cinacalcet initiates or discontinues therapy with a strong inhibitor (e.g. ketoconazole, itraconazole, telithromycin, voriconazole, ritonavir) or inducer (e.g. rifampicin) of this enzyme.

In vitro data indicate that cinacalcet is in part metabolised by CYP1A2. Smoking induces CYP1A2; the clearance of cinacalcet was observed to be 36-38% higher in smokers than non-smokers. The effect of CYP1A2 inhibitors (e.g. fluvoxamine, ciprofloxacin) on cinacalcet plasma levels has not been studied. Dose adjustment may be necessary if a patient starts or stops smoking or when concomitant treatment with strong CYP1A2 inhibitors is initiated or discontinued.

Calcium carbonate: Co-administration of calcium carbonate (single 1,500 mg dose) did not alter the pharmacokinetics of cinacalcet.

Sevelamer: Co-administration of sevelamer (2400 mg tid) did not affect the pharmacokinetics of cinacalcet.

Pantoprazole: Co-administration of pantoprazole (80 mg od) did not alter the pharmacokinetics of cinacalcet.

Effect of cinacalcet on other medications

Medicinal products metabolised by the enzyme P450 2D6 (CYP2D6): Cinacalcet is a strong inhibitor of CYP2D6. Dose adjustments of concomitant medicinal products may be required when Cinacalcet is administered with individually titrated, narrow therapeutic index substances that are predominantly metabolised by CYP2D6 (e.g. flecainide, propafenone, metoprolol, desipramine, nortriptyline, clomipramine).

Desipramine: Concurrent administration of 90 mg cinacalcet once daily with 50 mg desipramine, a tricyclic antidepressant metabolised primarily by CYP2D6, significantly increased desipramine exposure 3.6-fold (90 % CI 3.0, 4.4) in CYP2D6 extensive metabolisers.

Dextromethorphan: Multiple doses of 50 mg cinacalcet increased the AUC of 30 mg dextromethorphan (metabolised primarily by CYP2D6) by 11-fold in CYP2D6 extensive metabolisers.

Warfarin: Multiple oral doses of cinacalcet did not affect the pharmacokinetics or pharmacodynamics (as measured by prothrombin time and clotting factor VII) of warfarin.

The lack of effect of cinacalcet on the pharmacokinetics of R-and S-warfarin and the absence of auto-induction upon multiple dosing in patients indicates that cinacalcet is not an inducer of CYP3A4, CYP1A2 or CYP2C9 in humans.

Midazolam: Co-administration of cinacalcet (90 mg) with orally administered midazolam (2 mg), a CYP3A4 and CYP3A5 substrate, did not alter the pharmacokinetics of midazolam. These data suggest that cinacalcet would not affect the pharmacokinetics of those classes of medicines that are metabolized by CYP3A4 and CYP3A5, such as certain immunosuppressants, including ciclosporin and tacrolimus.

Pregnancy

There are no clinical data from the use of cinacalcet in pregnant women. Animal studies do not indicate direct harmful effects with respect to pregnancy, parturition or postnatal development. No embryonal/fetal toxicities were seen in studies in pregnant rats and rabbits with the exception of decreased fetal body weights in rats at doses associated with maternal toxicities (see section 5.3). Cinacalcet should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

It is not known whether cinacalcet is excreted in human milk. Cinacalcet is excreted in the milk of lactating rats with a high milk to plasma ratio. Following careful benefit/risk assessment, a decision should be made to discontinue either breast-feeding or treatment with Cinacalcet.

Fertility

There are no clinical data relating to the effect of cinacalcet on fertility. There were no effects on fertility in animal studies.

Dizziness and seizures, which may have major influence on the ability to drive and use machines, have been reported by patients taking cinacalcet (see section 4.4).

a) Summary of the safety profile

Secondary hyperparathyroidism, parathyroid carcinoma and primary hyperparathyroidism

Based on available data from patients receiving cinacalcet in placebo controlled studies and single-arm studies the most commonly reported adverse reactions were nausea and vomiting. Nausea and vomiting were mild to moderate in severity and transient in nature in the majority of patients. Discontinuation of therapy as a result of undesirable effects was mainly due to nausea and vomiting.

b) Tabulated list of adverse reactions

Adverse reactions, considered at least possibly attributable to cinacalcet treatment in the placebo controlled studies and single-arm studies based on best-evidence assessment of causality are listed below using the following convention: very common (≥ 1/10); common (≥ 1/100 to < 1/10); uncommon (≥ 1/1,000 to < 1/100); rare (≥ 1/10,000 to < 1/1,000); very rare (< 1/10,000).

Incidence of adverse reactions from controlled clinical studies and post-marketing experience are:

† see section 4.4

*see section c

c) Description of selected adverse reactions

Hypersensitivity reactions

Hypersensitivity reactions including angioedema and urticaria have been identified during post-marketing use of cinacalcet. The frequencies of the individual preferred terms including angioedema and urticaria cannot be estimated from available data.

Hypotension and/or worsening heart failure

There have been reports of idiosyncratic cases of hypotension and/or worsening heart failure in cinacalcet-treated patients with impaired cardiac function in post-marketing safety surveillance, the frequencies of which cannot be estimated from available data.

QT prolongation and ventricular arrhythmia secondary to hypocalcaemia

QT prolongation and ventricular arrhythmia secondary to hypocalcaemia have been identified during post-marketing use of cinacalcet, the frequencies of which cannot be estimated from available data (see section 4.4).

d) Paediatric population

Cinacalcet is not indicated for use in paediatric patients.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via Yellow Card Scheme

Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

Doses titrated up to 300 mg once daily have been administered to adult patients receiving dialysis without adverse outcome. A daily dose of 3.9 mg/kg was prescribed to a pediatric patient receiving dialysis in a clinical study with subsequent mild stomach ache, nausea and vomiting.

Overdose of Cinacalcet may lead to hypocalcaemia. In the event of overdose, patients should be monitored for signs and symptoms of hypocalcaemia and treatment should be symptomatic and supportive. Since cinacalcet is highly protein-bound, haemodialysis is not an effective treatment for overdose.

Pharmacotherapeutic group: Calcium homeostasis, anti-parathyroid agents. ATC code: H05BX01.

Mechanism of action

The calcium sensing receptor on the surface of the chief cell of the parathyroid gland is the principal regulator of PTH secretion. Cinacalcet is a calcimimetic agent which directly lowers PTH levels by increasing the sensitivity of the calcium sensing receptor to extracellular calcium. The reduction in PTH is associated with a concomitant decrease in serum calcium levels.

Reductions in PTH levels correlate with cinacalcet concentration.

After steady state is reached, serum calcium concentrations remain constant over the dosing interval.

Secondary Hyperparathyroidism

Adults

Three, 6-month, double-blind, placebo-controlled clinical studies were conducted in ESRD patients with uncontrolled secondary HPT receiving dialysis (n=1136). Demographic and baseline characteristics were representative of the dialysis patient population with secondary HPT. Mean baseline iPTH concentrations across the 3 studies were 733 and 683 pg/mL (77.8 and 72.4 pmol/L) for the cinacalcet and placebo groups, respectively. 66% of patients were receiving vitamin D sterols at study entry, and > 90% were receiving phosphate binders. Significant reductions in iPTH, serum calcium-phosphorus product (Ca x P), calcium, and phosphorus were observed in the cinacalcet treated patients compared with placebo-treated patients receiving standard of care, and the results were consistent across the 3 studies. In each of the studies, the primary endpoint (proportion of patients with an iPTH ≤ 250 pg/mL (≤ 26.5 pmol/L)) was achieved by 41%, 46% and 35% of patients receiving cinacalcet, compared with 4%, 7% and 6% of patients receiving placebo. Approximately 60% of cinacalcet-treated patients achieved a ≥ 30% reduction in iPTH levels and this effect was consistent across the spectrum of baseline iPTH levels. The mean reductions in serum Ca x P, calcium, and phosphorus were 14%, 7% and 8%, respectively.

Reductions in iPTH and Ca x P were maintained for up to 12 months of treatment. Cinacalcet decreased iPTH and Ca x P, calcium and phosphorus levels regardless of baseline iPTH or Ca x P level, dialysis modality (PD versus HD), duration of dialysis, and whether or not vitamin D sterols were administered.

Reductions in PTH were associated with non-significant reductions of bone metabolism markers (bone specific alkaline phosphatase, N-telopeptide, bone turnover and bone fibrosis). In post-hoc analyses of pooled data from 6 and 12 months' clinical studies, Kaplan-Meier estimates of bone fracture and parathyroidectomy were lower in the cinacalcet group compared with the control group.

Investigational studies in patients with CKD and secondary HPT not undergoing dialysis indicated that cinacalcet reduced PTH levels to a similar extent as in patients with ESRD and secondary HPT receiving dialysis. However, efficacy, safety, optimal doses and treatment targets have not been established in treatment of predialytic renal failure patients. These studies show that CKD patients not undergoing dialysis treated with cinacalcet have an increased risk for hypocalcaemia compared with cinacalcet-treated ESRD patients receiving dialysis, which may be due to lower baseline calcium levels and/or the presence of residual kidney function.

EVOLVE (EValuation of Cinacalcet Therapy to Lower CardioVascular Events) was a randomized, double-blind clinical study evaluating cinacalcet vs. placebo for the reduction of the risk of all-cause mortality and cardiovascular events in 3,883 patients with secondary HPT and CKD receiving dialysis. The study did not meet its primary objective of demonstrating a reduction in risk of all-cause mortality or cardiovascular events including myocardial infarction, hospitalization for unstable angina, heart failure or peripheral vascular event (HR 0.93; 95% CI: 0.85, 1.02; p = 0.112). After adjusting for baseline characteristics in a secondary analysis, the HR for the primary composite endpoint was 0.88; 95% CI: 0.79, 0.97.

Parathyroid carcinoma and Primary Hyperparathyroidism

In one study, 46 patients (29 with parathyroid carcinoma and 17 with primary HPT and severe hypercalcaemia who had failed or had contraindications to parathyroidectomy) received cinacalcet for up to 3 years (mean of 328 days for patients with parathyroid carcinoma and mean of 347 days for patients with primary HPT). Cinacalcet was administered at doses ranging from 30 mg twice daily to 90 mg four times daily. The primary endpoint of the study was a reduction of serum calcium of ≥ 1 mg/dL (≥ 0.25 mmol/L). In patients with parathyroid carcinoma, mean serum calcium declined from 14.1 mg/dL to 12.4 mg/dL (3.5 mmol/L to 3.1 mmol/L), while in patients with primary HPT, serum calcium levels declined from 12.7 mg/dL to 10.4 mg/dL (3.2 mmol/L to 2.6 mmol/L). Eighteen of 29 patients (62 %) with parathyroid carcinoma and 15 of 17 subjects (88 %) with primary HPT achieved a reduction in serum calcium of ≥ 1 mg/dL (≥ 0.25 mmol/L).

In a 28-week placebo-controlled study, 67 patients with primary HPT who met criteria for parathyroidectomy on the basis of corrected total serum calcium (> 11.3 mg/dL (2.82 mmol/L) but ≤ 12.5 mg/dL (3.12 mmol/L), but who were unable to undergo parathyroidectomy were included. Cinacalcet was initiated at a dose of 30 mg twice daily and titrated to maintain a corrected total serum calcium concentration within the normal range. A significantly higher percentage of cinacalcet treated patients achieved mean corrected total serum calcium concentration ≤ 10.3 mg/dL (2.57 mmol/L) and ≥ 1 mg/dL (0.25 mmol/L) decrease from baseline in mean corrected total serum calcium concentration, when compared with the placebo treated patients (75.8% versus 0% and 84.8% versus 5.9% respectively).

Absorption

After oral administration of cinacalcet, maximum plasma cinacalcet concentration is achieved in approximately 2 to 6 hours. Based on between-study comparisons, the absolute bioavailability of cinacalcet in fasted subjects has been estimated to be about 20-25%. Administration of Cinacalcet with food results in an approximate 50 – 80% increase in cinacalcet bioavailability. Increases in plasma cinacalcet concentration are similar, regardless of the fat content of the meal.

At doses above 200 mg, the absorption was saturated probably due to poor solubility.

Distribution

The volume of distribution is high (approximately 1000 litres), indicating extensive distribution. Cinacalcet is approximately 97% bound to plasma proteins and distributes minimally into red blood cells.

After absorption, cinacalcet concentrations decline in a biphasic fashion with an initial half-life of approximately 6 hours and a terminal half-life of 30 to 40 hours. Steady state levels of cinacalcet are achieved within 7 days with minimal accumulation. The pharmacokinetics of cinacalcet does not change over time.

Biotransformation

Cinacalcet is metabolised by multiple enzymes, predominantly CYP3A4 and CYP1A2 (the contribution of CYP1A2 has not been characterised clinically). The major circulating metabolites are inactive.

Based on in vitro data, cinacalcet is a strong inhibitor of CYP2D6, but is neither an inhibitor of other CYP enzymes at concentrations achieved clinically, including CYP1A2, CYP2C8, CYP2C9, CYP2C19, and CYP3A4 nor an inducer of CYP1A2, CYP2C19 and CYP3A4.

Elimination

After administration of a 75 mg radiolabelled dose to healthy volunteers, cinacalcet was rapidly and extensively metabolised by oxidation followed by conjugation. Renal excretion of metabolites was the prevalent route of elimination of radioactivity. Approximately 80% of the dose was recovered in the urine and 15% in the faeces.

Linearity/non-linearity

The AUC and C_max of cinacalcet increase approximately linearly over the dose range of 30 to 180 mg once daily.

Pharmacokinetic/pharmacodynamic relationship(s)

Soon after dosing, PTH begins to decrease until a nadir at approximately 2 to 6 hours post-dose, corresponding with cinacalcet C_max. Thereafter, as cinacalcet levels begin to decline, PTH levels increase until 12 hours post-dose, and then PTH suppression remains approximately constant to the end of the once-daily dosing interval. PTH levels in cinacalcet clinical trials were measured at the end of the dosing interval.

Elderly: There are no clinically relevant differences due to age in the pharmacokinetics of cinacalcet.

Renal Insufficiency: The pharmacokinetic profile of cinacalcet in patients with mild, moderate, and severe renal insufficiency and those on haemodialysis or peritoneal dialysis is comparable to that in healthy volunteers.

Hepatic Insufficiency: Mild hepatic impairment did not notably affect the pharmacokinetics of cinacalcet. Compared to subjects with normal liver function, average AUC of cinacalcet was approximately 2-fold higher in subjects with moderate impairment and approximately 4-fold higher in subjects with severe impairment. The mean half-life of cinacalcet is prolonged by 33% and 70% in patients with moderate and severe hepatic impairment, respectively. Protein binding of cinacalcet is not affected by impaired hepatic function. Because doses are titrated for each subject based on safety and efficacy parameters, no additional dose adjustment is necessary for subjects with hepatic impairment (see sections 4.2 and 4.4).

Gender: Clearance of cinacalcet may be lower in women than in men. Because doses are titrated for each subject, no additional dose adjustment is necessary based on gender.

Paediatric Population: The pharmacokinetics of cinacalcet was studied in paediatric patients with ESRD receiving dialysis aged 3 to 17 years of age. After single and multiple once daily oral doses of cinacalcet, plasma cinacalcet concentrations (C_max and AUC values after normalisation by dose and weight) were similar to those observed in adult patients.

A population pharmacokinetic analysis was performed to evaluate the effects of demographic characteristics. This analysis showed no significant impact of age, sex, race, body surface area, and body weight on cinacalcet pharmacokinetics.

Smoking: Clearance of cinacalcet is higher in smokers than in non-smokers, likely due to induction of CYP1A2-mediated metabolism. If a patient stops or starts smoking, cinacalcet plasma levels may change and dose adjustment may be necessary.

Cinacalcet was not teratogenic in rabbits when given at a dose of 0.4 times, on an AUC basis, the maximum human dose for secondary HPT (180 mg daily). The non-teratogenic dose in rats was 4.4 times, on an AUC basis, the maximum dose for secondary HPT. There were no effects on fertility in males or females at exposures up to 4 times a human dose of 180 mg/day (safety margins in the small population of patients administered a maximum clinical dose of 360 mg daily would be approximately half those given above).

In pregnant rats, there were slight decreases in body weight and food consumption at the highest dose. Decreased fetal weights were seen in rats at doses where dams had severe hypocalcaemia. Cinacalcet has been shown to cross the placental barrier in rabbits.

Cinacalcet did not show any genotoxic or carcinogenic potential. Safety margins from the toxicology studies are small due to the dose-limiting hypocalcaemia observed in the animal models. Cataracts and lens opacities were observed in the repeat dose rodent toxicology and carcinogenicity studies, but were not observed in dogs or monkeys or in clinical studies where cataract formation was monitored. Cataracts are known to occur in rodents as a result of hypocalcaemia.

In in vitro studies, IC₅₀ values for the serotonin transporter and K_ATP channels were found to be 7 and 12 fold greater, respectively, than the EC₅₀ for the calcium-sensing receptor obtained under the same experimental conditions. The clinical relevance is unknown, however, the potential for cinacalcet to act on these secondary targets cannot be fully excluded.

In toxicity studies in juvenile dogs, tremors secondary to decreased serum calcium, emesis, decreased body weight and body weight gain, decreased red cell mass, slight decreases in bone densitometry parameters, reversible widening of the growth plates of long bones, and histological lymphoid changes (restricted to the thoracic cavity and attributed to chronic emesis) were observed. All of these effects were seen at a systemic exposure, on an AUC basis, approximately equivalent to the exposure in patients at the maximum dose for secondary HPT.

o Tablet core:

microcrystalline cellulose

low substituted hydroxyl propyl

cellulose, lactose monohydrate

silica colloidal anhydrous

magnesium stearate

o Tablet coating:

HPMC 2910/Hypromellose (E464)

Lactose Monohydrate

Titanium dioxide (E171)

Triacetin

FD&C Blue #2/Indigo Carmine AL 3%- 5% (E132)

Iron Oxide Yellow (E172)

Not applicable.

Blister pack: 3 years

HDPE bottle pack :2 years

This medicinal product does not require any special storage conditions.

Aclar/PVC/Aluminium unit dose blister

Pack sizes: 28s and 84s tablets

Not all pack sizes may be marketed.

High Density Polyethylene (HDPE) bottle pack with 30 tablets.

No special requirements.

Any unused medicinal product or waste material should be disposed of in accordance with local requirements.