1. Name Of The Medicinal Product
Losartan potassium 100 mg film-coated tablets
2. Qualitative And Quantitative Composition
Each film-coated tablet contains 100 mg losartan potassium, equivalent to 91.6 mg losartan
Excipient:
Losartan 100 mg film-coated tablets: lactose
For a full list of excipients, see section 6.1.
3. Pharmaceutical Form
White, oval-shaped, film-coated tablet with a score line on both sides. The film-coated tablet can be divided into equal halves.
4. Clinical Particulars
4.1 Therapeutic Indications
• Treatment of essential hypertension in adults and in children and adolescents 6-18 years of age.
• Treatment of chronic heart failure (in patients especially cough, or contraindication. Patients with heart failure who have been stabilised with an ACE inhibitor should not be switched to losartan. The patients should have a left ventricular ejection fraction
4.2 Posology And Method Of Administration
Losartan tablets should be swallowed with a glass of water
Losartan tablets may be administered with or without food.
Hypertension
The usual starting and maintenance dose is 50 mg once daily for most patients. The maximal antihypertensive effect is attained 3-6 weeks after initiation of therapy. Some patients may receive an additional benefit by increasing the dose to 100 mg once daily (in the morning). Losartan may be administered with other antihypertensive agents, especially with diuretics (e.g. hydrochlorothiazide).
Heart Failure
The usual initial dose of Losartan in patients with heart failure is 12.5 mg once daily. The dose should generally be titrated at weekly intervals (i.e. 12.5 mg daily, 25 mg daily, 50 mg daily) to the usual maintenance dose of 50 mg once daily, as tolerated by the patient.
Special populations:
Use in patients with intravascular volume depletion:
For patients with intravascular volume-depletion (e.g. those treated with high-dose diuretics), a starting dose of 25 mg once dailyshould be considered (see section 4.4).
Use in patients with renal impairment and haemodialysis patients:
No initial dosage adjustment is necessary in patients with renal impairment and in haemodialysis patients.
Use in patients with hepatic impairment
A lower dose should be considered for patients with a history of hepatic impairment. There is no therapeutic experience in patients with severe hepatic impairment. Therefore, losartan is not recommended in patients with severe hepatic impairment (see sections 4.3 and 4.4).
Use in paediatric patients
There are limited data on the efficacy and safety of losartan in children and adolescents aged 6-18 years old for the treatment of hypertension (see section 5.1). Limited pharmacokinetic data are available in hypertensive children above one month of age (see section 5.2).
For patients who can swallow tablets, the recommended dose is 25 mg once daily in patients>20 to <50 kg. In exceptional cases the dose can be increased to a maximum of 50 mg once daily. Dosage should be adjusted according to blood pressure response.
In patients>50 kg, the usual dose is 50 mg once daily. In exceptional cases the dose can be adjusted to a maximum of 100 mg once daily. Doses above 1.4 mg/kg (or in excess of 100 mg) daily have not been studied in paediatric patients.
Losartan is not recommended for use in children under 6 years old, as limited data are available in these patient groups.
It is not recommended in children with glomerular filtration rate < 30 ml/min / 1.73 m², as no data are available (see also section 4.4).
Losartan is also not recommended in children with hepatic impairment (see also section 4.4).
Use in the elderly
Although consideration should be given to initiating therapy with 25 mg in patients over 75 years of age, dosage adjustment is not usually necessary for the elderly.
4.3 Contraindications
Hypersensitivity to the active substance or to any of the excipients (see section 4.4 and 6.1)
Second and third trimesters of pregnancy (see section 4.4 and 4.6)
Severe hepatic impairment
4.4 Special Warnings And Precautions For Use
Hypersensitivity
Angiooedema. Patients with a history of angiooedema (swelling of the face, lips, throat, and/or tongue) should be closely monitored (see section 4.8).
Hypotension and Electrolyte/Fluid Imbalance
Symptomatic hypotension, especially after the first dose and after increasing of the dose, may occur in patients who are volume- and/or sodium-depleted by vigorous diuretic therapy, dietary salt restriction, diarrhoea or vomiting. These conditions should be corrected prior to administration of Losartan; or a lower starting dose should be used (see section 4. 2). This also applies to children.
Electrolyte imbalances
Electrolyte imbalances are common in patients with renal impairment, with or without diabetes, and should be addressed. In a clinical study conducted in type 2 diabetic patients with nephropathy, the incidence of hyperkalemia was higher in the group treated with Losartan as compared to the placebo group (see section 4.8) Therefore, the plasma concentrations of potassium as well as creatinine clearance values should be closely monitored, in particular, patients with heart failure and a Creatinine Clearance between 30-50 ml/min should be closely monitored.
The concomitant use of potassium sparing diuretics, potassium supplements and potassium containing salt substitutes with losartan is not recommended (sec section 4.5).
Hepatic Impairment
Based on pharmacokinetic data which demonstrate significantly increased plasma concentrations of losartan in cirrhotic patients, a lower dose should be considered for patients with a history of hepatic impairment. There is no therapeutic experience with losartan in patients with severe hepatic impairment. Therefore losartan must not be administered in patients with severe hepatic impairment (see sections 4.2, 4.3 and 5.2).
Losartan is also not recommended in children with hepatic impairment (see section 4.2).
Renal Impairment
As a consequence of inhibiting the renin-angiotensin system, changes in renal function including renal failure have been reported (in particular, in patients whose renal function is dependent on the renin angiotensin aldosterone system such as those with severe cardiac insufficiency or pre-existing renal dysfunction). As with other drugs that affect the renin-angiotensin-aldosterone system, increases in blood urea and serum creatinine have also been reported in patients with bilateral renal artery stenosis or stenosis of the artery to a solitary kidney; these changes in renal function may be reversible upon discontinuation of therapy. Losartan should be used with caution in patients with bilateral renal artery stenosis or stenosis of the artery to a solitary kidney.
Use in paediatric patients with renal impairment
Losartan is not recommended in children with glomerular filtration rate < 30ml/min/1.73 m2 as no data are available (see section 4.2).
Renal function should be regularly monitored during treatment with losartan as it may deteriorate. This applies particularly when losartan is given in the presence of other conditions (fever, dehydration) likely to impair renal function.
Concomitant use of losartan and ACE-inhibitors has shown to impair renal function. Therefore, concomitant use is not recommended.
Renal transplantation
There is no experience in patients with recent kidney transplantation.
Primary hyperaldosteronism
Patients with primary aldosteronism generally will not respond to antihypertensive medicinal products acting through inhibition ofthe renin-angiotensin system. Therefore, the use of Losartan tablets is not recommended.
Coronary heart disease and cerebrovascular disease
As with any antihypertensive agents, excessive blood pressure decrease in patients with ischaemic cardiovascular and cerebrovascular disease could result in a myocardial infarction or stroke.
Heart failure
In patients with heart failure, with or without renal impairment, there is - as with other medicinal products acting on the renin-angiotensin system - a risk of severe arterial hypotension, and (often acute) renal impairment.
There is no sufficient therapeutic experience with losartan in patients with heart failure and concomitant severe renal impairment, in patients with severe heart failure (NYHA class IV) as well as in patients with heart failure and symptomatic life threatening cardiac arrhythmias. Therefore, losartan should be used with caution in these patient groups. The combination of losartan with a beta-blocker should be used with caution (see section 5.1).
Aortic and mitral valve stenosis, obstructive hypertrophic cardiomyopathy
As with other vasodilators, special caution is indicated in patients suffering from aortic or mitral stenosis, or obstructive hypertrophic cardiomyopathy.
Excipients
Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take this medicine.
Pregnancy
AIIRAs should not be initiated during pregnancy. Unless continued AIIRA therapy is considered essential, patients planning pregnancy should be changed to alternative anti-hypertensive treatments which have an established safety profile for use in pregnancy. When pregnancy is diagnosed, treatment with AIIRAs should be stopped immediately, and, if appropriate, alternative therapy should be started (see sections 4.3 and 4.6).
Other warnings and precautions:
As observed for antiotensin converting enzyme inhibitors, losartan and the other angiotensin antagonists are apparently less effective in lowering blood pressure in black people than in non-blacks, possibly because of higher prevalence of low-renin states in the black hypertensive population.
4.5 Interaction With Other Medicinal Products And Other Forms Of Interaction
Other antihypertensive agents may increase the hypotensive effects of losartan. Concomitant use with other substances inducing hypotension (like tricyclic antidepressants, antipsychotics, baclofen, and amifostine)may increase the risk of hypotension.
Losartan is predominantly metabolised by cytochrome P450 (CYP) 2C9 to the active carboxy-acid metabolite. In a clinical trial it was found that fluconazole (inhibitor of CYP2C9) decreases the exposure to the active metabolite by approximately 50%. It was found that concomitant treatment of losartan with rifampicine (inducer of metabolism enzymes) gave a 40% reduction in plasma concentration of the active metabolite. The clinical relevance of this effects is unknown. No difference in exposure was found with concomitantly treatment with fluvastatin (weak inhibitor of CYP2C9).
As with other drugs that block angiotensin II or its effects, concomitant use of other drugs which retain potassium (e.g. potassium-sparing diuretics: amiloride, triamteren, spironolactone) or may increase potassium levels (e.g. heparin), potassium supplements or salt substitutes containing potassium may lead to increases in serum potassium. Co-medication is not advisable.
Reversible increases in serum lithium concentrations and toxicity have been reported during concomitant administration of lithium with ACE inhibitors. Very rare cases have also been reported with angiotensin II receptor antagonists. Co-administration of lithium and losartan should be undertaken with caution. If this combination proves essential, serum lithium level monitoring is recommended during concomitant use.
When angiotensin II antagonists are administered simultaniously with NSAIDs (i.e. selective COX-2 inhibitors, acetylsalicylic acid at anti-inflammatory doses and non-selective NSAIDs), attenuation of the antihypertensive effect may occur.
Concomitant use of angiotensin II antagonists or diuretics and NSAIDs may lead to an increased risk of worsening of renal function, including possible acute renal failure, and an increase in serum potassium, especially in patients with poor pre-existing renal function. The combination should be administered with caution, especially in the elderly. Patients should be adequately hydrated and consideration should be given to monitoring renal function after initiation of concomitant therapy, and periodically thereafter.
4.6 Pregnancy And Lactation
Pregnancy
The use of AIIRAs is not recommended during the first trimester of pregnancy (see section 4.4).The use of AIIRAs is contra-indicated during the 2nd and 3rd trimesters of pregnancy (see section 4.3 and 4.4).
|
Epidemiological evidence regarding the risk of teratogenicity following exposure to ACE inhibitors during the first trimester of pregnancy has not been conclusive; however a small increase in risk cannot be excluded. Whilst there is no controlled epidemiological data on the risk with Angiotensin II Receptor Inhibitors ( AIIRAs), similar risks may exist for this class of drugs. Unless continued AIIRA therapy is considered essential, patients planning pregnancy should be changed to alternative anti-hypertensive treatments which have an established safety profile for use in pregnancy. When pregnancy is diagnosed, treatment with AIIRAs should be stopped immediately, and, if appropriate, alternative therapy should be started.
Exposure to AIIRA therapy during the second and third trimesters is known to induce human fetotoxicity (decreased renal function, oligohydramnios, skull ossification retardation) and neonatal toxicity (renal failure, hypotension, hyperkalaemia) (see section 5.3).
Should exposure to AIIRAs have occurred from the second trimester of pregnancy, ultrasound check of renal function and skull is recommended.
Infants whose mothers have taken AIIRAs should be closely observed for hypotension (see sections 4.3 and 4.4).
Lactation
Because no information is availabel regarding the use of Losartan during breastfeeding, Losartan is not recommended and alternative treatments with better established safety profiles during breast-feeding are preferable, especially while nursing a newborn or preterm infant.
4.7 Effects On Ability To Drive And Use Machines
No studies on the effects on the ability to drive and use machines have been performed.
However, when driving vehicles or operating machinery it must be borne in mind that dizziness or drowsiness may occasionally occur when taking antihypertensive therapy, in particular during initiation of treatment or when the dose is increased.
4.8 Undesirable Effects
Losartan has been evaluated in clinical studies as follows:
• In controlled clinical trials in approximately 3300 adult patients 18 years of age and older for essential hypertension
• In a controlled clinical trial in 9193 hypertensive patients 55 to 80 years of age with left ventricular hypertrophy
• In a controlled clinical trial in approximately 3900 patients 20 years of age and older with chronic heart failure
• In a controlled clinical trial in 1513 type 2 diabetic patients 31 years of age and older with proteinuria
• In a controlled clinical trial in 177 hypertensive paediatric patients 6 to 16 years of age
In these clinical trials, the most common adverse event was dizziness.
The frequency of adverse events listed below is defined using the following convention:
very common (
In controlled clinical trials for essential hypertension , hypertensive patients with left ventricular hypertrophy, chronic heart failure as well as for hypertension and type 2 diabetes mellitus with renal disease, the most common adverse event was dizziness.
Hypertension
In controlled clinical trials, of approximately 3300 adult patients 18 years of age and older, for essential hypertension with losartan the following adverse events were reported
Nervous system disorders:
Common: dizziness, vertigo
Uncommon: somnolence, headache, sleep disorders
Cardiac disorders:
Uncommon: palpitations, angina pectoris
Vascular disorders:
Uncommon: symptomatic hypotension (especially in patients with intravascular volume depletion, e.g. patients with severe heart failure or under treatment with high dose diuretics), dose-related orthostatic effects, rash
Gastrointestinal disorders:
Uncommon: abdominal pain, obstipation
General disorders and administration site conditions:
Uncommon: asthenia, fatigue, oedema
Investigations:
In controlled clinical trials, clinically important changes in standard laboratory parameters were rarely associated with administration of Losartan tablets. Elevations of ALT occurred rarely and usually resolved upon discontinuation of therapy. Hyperkalaemia (serum potassium>5.5 mmol/l) occurred in 1.5 % of patients in hypertension clinical trials.
Hypertensive patients with left ventricular hypertrophy
In a controlled clinical trial in 9193 hypertensive patients55 to 80 years of agewith left ventricular hypertrophy the following adverse events were reported:
Nervous system disorders:
common: dizziness
Ear and labyrinth disorders:
common: vertigo
General disorders and administration site conditions:
common: asthenia/fatigue
Chronic heart failure
In a controlled clinical trial in approximately 3900 patients 20 years of age and older with cardiac insufficiency the following adverse events were reported:
Nervous system disorders:
uncommon: dizziness, headache
rare: paraesthesia
Cardiac disorders:
rare: syncope, artrial fibrillation, cerebrovascular accident
Vascular disorders:
uncommon: hypotension, including orthostatic hypotension
Respiratory, thoracic and mediastinal disorders:
uncommon: dyspnoea
Gastrointestinal disorders:
uncommon: diarrhoea, nausea, vomiting
Skin and subcutanous tissue disorders:
uncommon: urticaria, pruritus, rash
General disorders and administration site conditions:
uncommon: asthenia/fatigue
Investigations:
uncommon: increase in blood urea, serum creatinine and serum potassium has been reported.
Hypertension and type 2 diabetes with renal disease
In a controlled clinical trial in 1513 type 2 diabetic patients 31 years of age and older with proteinuria (RENAAL study, see section 5.1) the most common drug-related adverse events which were reported for losartan are as follows:
Nervous system disorders:
common: dizziness
Vascular disorders:
common: hypotension
General disorders and administration site conditions:
common: asthenia/fatigue
Investigations:
common: hypoglycaemia, hyperkalaemia
The following adverse events occured more often in patients receiving losartan than placebo:
Blood and lymphatic system disorders:
not known: anaemia
Cardiac disorders:
not known: syncope, palpitations
Vascular disorders:
not known: orthostatic hypotension
Gastrointestinal disorders:
not known: diarrhoea
Muscoskeletal and connective tissue disorders:
not known: back pain
Renal and urinary disorders:
not known: urinary tract infections
General disorders and administration site conditions:
not known: flu-like symptoms
Investigations:
In a clinical study conducted in type 2 diabetic patients with nephropathy, 9.9 % of patients treated with Losartan tablets developed hyperkalaemia>5.5 mEq/l and 3.4 % of patients treated with placebo
Post-marketing experience
The following adverse events have been reported in post-marketing experience:
Blood and lymphatic system disorders:
not known: Anaemia:thrombocytopenia
Ear and labyrinth disorders:
not known: tinnitus
Immune system disorders:
rare: hypersensitivity: anaphylactic reactions, angiooedema including swelling of the larynx and glottis causing airway obstruction and/or swelling of the face, lips, pharynx, and/or tongue; in some of these patients angiooedema had been reported in the past in connection with the administration of other medicines, including ACE inhibitors; vasculitis, including Henoch-Schonlein purpura.
Nervous system disorders:
not known: migraine
Respiratory, thoracic and mediastinal disorders:
not known: cough
Gastrointestinal disorders:
not known: diarrhoea, pancreatitis
General disorders and administration site conditions:
not known: malaise
Hepatobiliary disorders:
rare: hepatitis
not known: liver function abnormalities
Skin and subcutaneous tissue disorders:
not known: urticaria, pruritus, rash
Muscoskeletal and connective tissue disorders:
not known: myalgia, arthralgia, rhabdomyolysis
Reproductive system and breast disorders:
not known: erectile dysfunction/impotence
Renal and urinary disorders:
As a consequence of inhibiting the renin-angiotensin-aldosterone system, changes in renal function including renal failure have been reported in patients at risk; these changes in renal function may be reversible upon discontinuation of therapy (see section 4.4)
Investigations::
not known: hyponatraemia
Psychiatric disorders:
not known: depression
Paediatric population
The adverse experience profile for paediatric patients appears to be similar to that seen in adult patients. Data in the paediatric population are limited.
4.9 Overdose
Symptoms of intoxication
Limited data are available with regard to overdose in humans. The most likely symptoms, depending on the extent of overdose, are hypotension, tachycardia, possibly bradycardia.
Treatment of intoxications
If symptomatic hypotension should occur, supportive treatment should be instituted. Measures are depending on the time of drug intake and kind and severity of symptoms. Stabilisation of the circulatory system should be given priority. After oral intake the administration of a sufficient dose of activated charcoal is indicated. Afterwards, close monitoring of the vital parameters should be performed. Vital parameters should be corrected if necessary.
Neither losartan nor the active metabolite can by removed by haemodialysis.
5. Pharmacological Properties
Pharmacotherapeutic group: Angiotensin II Receptor Antagonists, ATC code: C09CA01
5.1 Pharmacodynamic Properties
Losartan is a synthetic oral angiotensin-II receptor (type AT1) antagonist. Angiotensin II, a potent vasoconstrictor, is the primary active hormone of the renin-angiotensin system and an important determinant of the pathophysiology of hypertension. Angiotensin II binds to the AT1 receptor found in many tissues (e.g. vascular smooth muscle, adrenal gland, kidneys, and the heart) and elicits several important biological actions, including vasoconstriction and the release of aldosterone. Angiotensin II also stimulates smooth-muscle cell proliferation.
Losartan selectively blocks the AT1 receptor. In vitro and in vivo, both losartan and its pharmacologically active carboxylic acid metabolite E-3174 block all physiologically relevant actions of angiotensin II, regardless of its source or route of synthesis.
Losartan does not have an agonist effect, nor does it block other hormone receptors or ion channels important in cardiovascular regulation. Furthermore, losartan does not inhibit ACE (kininase II), the enzyme that degrades bradykinin. Consequently, there is no potentiation of undesirable bradykinin-mediated effects.
During administration of losartan, removal of angiotensin II negative feedback on renin secretion leads to increased plasma-renin activity (PRA). Increases in PRA lead to increases in angiotensin II in plasma. Despite these increases, antihypertensive activity and suppression of plasma aldosterone concentration are maintained, indicating effective angiotensin II receptor blockade. After discontinuation of losartan, PRA and angiotensin II values fell within three days to baseline values.
Both losartan and its principal active metabolite have a far greater affinity for the AT1 receptor than for the AT2 receptor. The active metabolite is 10 to 40 times more effective than losartan on a weight for weight basis.
Hypertension studies
In controlled clinical studies, once-daily administration of losartan to patients with mild to moderate essential hypertension produced statistically significant reductions in systolic and diastolic blood pressure. Measurement of blood pressure 24 hours post-dose relative to 5-6 hours post-dose demonstrated blood pressure reduction over 24 hours; the natural diurnal rhythm was retained. Blood-pressure reduction at the end of the dosing interval was approximately 70-80% of the effect seen 5-6 hours post-dose.
Discontinuation of losartan in hypertensive patients did not result in an abrupt rise in blood pressure (rebound). Despite the marked decrease in blood pressure, losartan had no clinically significant effect on heart rate.
Losartan is equally effective in males and females, and in younger (below the age of 65 years) and older hypertensive patients.
ELITE I and ELITE II Study
In the ELITE Study carried out over 48 weeks in 722 patients with heart failure (NYHA Class II-IV, no difference was observed between the patients treated with Losartan and those treated with captopril was observed with regard to the primary endpoint of a long-term change in renal function. The observation of the ELITE I Study was that, compared with captopril, Losartan reduced the mortality risk, was not confirmed in the subsequent ELITE II Study.
In the ELITE II Study Losartan 50 mg once daily (starting dose 12.5 mg, increased to 25 mg, then 50 mg once daily) was compared with captopril 50 mg three times daily (starting dose 12.5 mg, increased to 25 mg and then to 50 mg three times daily). The primary endpoint of this prospective study was the all-cause mortality.
In this study 3152 patients with heart failure (NYHA Class Il-IV) were followed for almost two years (median: 1.5 years) in order to determine whether Losartan is superior to captopril in reducing all cause mortality. The primary endpoint did not show any statistically significant difference between Losartan and captopril in reducing all-cause mortality.
In both comparator-controlled (not placebo-controlled) clinical studies on patients with heart failure the tolerability of Losartan was superior to that of captopril, measured on the basis of a significantly lower rate of discontinuations of therapy on account of adverse events and a significantly lower frequency of cough.
An increased mortality was observed in ELITE II in the small subgroup (22% of all HF patients) taking beta-blockers at baseline.
Paediatric Population
The antihypertensive effect of Losartan was established in a clinical study involving 177 hypertensive paediatric patients 6 to 16 years of age with a body weight> 20 kg and a glomerular filtration rate> 30 ml/min/1.73 m². Patients who weighed>20kg to < 50 kg received either 2.5, 25 or 50 mg of losartan daily and patients who weighed> 50 kg received either 5, 50 or 100 mg of losartan daily. At the end of three weeks, losartan administration once daily lowered trough blood pressure in a dose-dependent manner.
Overall, there was a dose-response. The dose-response relationship became very obvious in the low dose group compared to the middle dose group (period I: -6.2 mmHg vs. -11.65 mmHg), but was attenuated when comparing the middle dose group with the high dose group (period I: -11.65 mmHg vs. -12.21 mmHg). The lowest doses studied, 2.5 mg and 5 mg, corresponding to an average daily dose of 0.07 mg/kg, did not appear to offer consistent antihypertensive efficacy.
These results were confirmed during period II of the study where patients were randomized to continue losartan or placebo, after three weeks of treatment. The difference in blood pressure increase as compared to placebo was largest in the middle dose group (6.70 mm Hg middle dose vs. 5.38 mmHg high dose). The rise in trough diastolic blood pressure was the same in patients receiving placebo and in those continuing losartan at the lowest dose in each group, again suggesting that the lowest dose in each group did not have significant antihypertensive effect.
Long-term effects of losartan on growth, puberty and general development have not been studied. The long-term efficacy of antihypertensive therapy with losartan in childhood to reduce cardiovascular morbidity and mortality has also not been established.
In hypertensive (N=60) and normotensive (N=246) children with proteinuria, the effect of losartan on proteinuria was evaluated in a 12-week placebo- and active-controlled (amlodipine) clinical study. Proteinuria was defined as urinary protein/creatinine ratio of
Overall, after 12 weeks of treatment, patients receiving losartan experienced a statistically significant reduction from baseline in proteinuria of 36% versus 1% increase in placebo/amlodipine group (p
5.2 Pharmacokinetic Properties
Absorption
Following oral administration, losartan is well absorbed and undergoes first-pass metabolism, forming an active carboxylic acid metabolite and other inactive metabolites. The systemic bioavailability of Losartan potassium is approx. 33%. Mean peak concentrations of losartan and its active metabolite are reached in 1 hour and in 3-4 hours, respectively.
Distribution
Both losartan and its active metabolite are
Biotransformation
About 14% of an intravenously or orally administered dose of losartan is converted to its active metabolite. Following oral and intravenous administration of 14C-labelled losartan potassium, circulating plasma radioactivity is primarily is attributed to losartan and its active metabolite. Minimal conversion of losartan to its active metabolite was seen in about one percent of individuals studied.
In addition to the active metabolite, inactive metabolites are formed.
Elimination
Plasma clearance of losartan and its active metabolite is about 600 ml/minute and 50 ml/minute, respectively. Renal clearance of losartan and its active metabolite is about 74 ml/minute and 26 ml/minute, respectively. When losartan is administered orally, about 4% of the dose is excreted unchanged in the urine, and about 6% of the dose is excreted in the urine as active metabolite. The pharmacokinetics of losartan and its active metabolite are linear with oral losartan potassium doses up to 200 mg.
Following oral administration, plasma concentrations of losartan and its active metabolite decline polyexponentially with a terminal half-life of about 2 hours and 6-9 hours, respectively. During once-daily dosing with 100 mg, neither losartan nor its active metabolite accumulates significantly in plasma.
Both biliary and urinary excretion contribute to the elimination of losartan and its metabolites. Following an oral dose/intravenous administration of 14C-labeled losartan in man, about 35% / 43% of radioactivity is recovered in the urine and 58%/50% in the faeces.
Characteristics in patients
In elderly hypertensive patients the plasma concentrations of losartan and its active metabolite do not differ essentially from those found in young hypertensive patients.
In female hypertensive patients the plasma levels of losartan were up to twice as high as in male hypertensive patients, while the plasma levels of the active metabolite did not differ between men and women.
In patients with mild to moderate alcohol-induced hepatic cirrhosis, the plasma levels of losartan and its active metabolite after oral administration were respectively 5 and 1.7 times higher than in young male volunteers (see section 4.2 and 4.4).
Plasma concentrations of losartan are not altered in patients with creatinine clearance above 10 ml/minute. Compared to patients with normal renal function, the AUC for losartan is approximately two times higher in haemodialysis patients.
The plasma concentrations of the active metabolite are not altered in patients with renal impairment or in haemodialysis patients.
Neither losartan nor the active metabolite can be removed by haemodialysis.
Pharmacokinetics in paediatric patients
The pharmacokinetics of losartan have been investigated in 50 hypertensive paediatric patients> 1 month to < 16 years of age following once daily oral administration of approximately 0.54 to 0.77 mg/ kg of losartan (mean doses).
The results showed that the active metabolite is formed from losartan in all age groups. The results showed roughly similar pharmacokinetic parameters of losartan following oral administration in infants and toddlers, preschool children, school age children and adolescents. The pharmacokinetic parameters for the metabolite differed to a greater extent between the age groups. When comparing preschool children with adolescents these differences became statistically significant. Exposure in infants/toddlers was comparatively high.
5.3 Preclinical Safety Data
Preclinical data reveal no special hazard for humans based on conventional studies of general pharmacology, genotoxicity and carcinogenic potential. In repeated dose toxicity studies, the administration of losartan induced a decrease in red blood cell parameters (erythrocytes, haemoglobin, haematocrit), a rise in urea-N in the serum and occasional rises in serum creatinine, a decrease in heart weight (without a histological correlate) and gastrointestinal changes (mucous membrane lesions, ulcers, erosions, haemorrhages). Like other substances that directly affect the renin-angiotensin system, losartan has been shown to induce adverse effects on late fetal development, resulting in fetal death and malformations.
6. Pharmaceutical Particulars
6.1 List Of Excipients
Core:
Lactose monohydrate
Cellulose microcrystalline
Maize starch
Croscarmellose sodium
Magnesium stearate
Film-Coat (OPADRY 20A58900 white):
Hydroxypropylcellulose
Hypromellose
Titanium dioxide E171
6.2 Incompatibilities
Not applicable.
6.3 Shelf Life
36 months
In-use shelf life for plastic bottle (HDPE): 12 weeks
6.4 Special Precautions For Storage
Do not store above 30°C.
6.5 Nature And Contents Of Container
Plastic bottle (HDPE) or blister pack (PVC/PE/PVDC blisters with aluminium foil lidding)
blister pack: 7, 14, 15, 21, 28, 30, 50, 56, 98, 280 (10 x 28) tablets
plastic bottle: 30, 50, 100 tablets
Not all pack sizes may be marketed.
6.6 Special Precautions For Disposal And Other Handling
Any unused product or waste material should be disposed of in accordance with local requirements.
7. Marketing Authorisation Holder
Winthrop Pharmaceuticals UK Limited
One Onslow Street
Guildford
Surrey
GU1 4YS, UK
Trading as: Winthrop Pharmaceuticals, PO Box 611, Guildford, Surrey, GU1 4YS, UK
8. Marketing Authorisation Number(S)
PL 17780/0327
9. Date Of First Authorisation/Renewal Of The Authorisation
03/06/2008
10. Date Of Revision Of The Text
28/08/2010
LEGAL STATUS
POM
