Pentostam Injection.

Sodium Stibogluconate equivalent to 100 mg pentavalent antimony in each ml.

Injection.

Pentostam is indicated for the following diseases:

Visceral leishmaniasis (kala azar).

Cutaneous leishmaniasis.

South American mucocutaneous leishmaniasis.

Pentostam may also be of value in the treatment of leishmaniasis recidivans and diffuse cutaneous leishmaniasis in the New World.

Note: Cutaneous and diffuse cutaneous leishmaniasis caused by Leishmania aethiopica infections are unresponsive to treatment with pentavalent antimony compounds, including Pentostam, at conventional dosage, but may respond slowly at higher dosage.

Route of administration

Except where otherwise stated, all doses should be given by the intravenous or intramuscular route (see Warnings and Precautions).

Due to the presence of particulates (size range 20 to 300 microns) Pentostam solution should be drawn up through a filter immediately prior to administration. These particulates are insoluble complexes formed by an interaction between product preservative and the antioxidant in the rubber stopper. Filters of pore size 5 micron or less and membrane types polyvinylidene difluoride, polyethersulphone, polysulphone, nylon, surfactant-free cellulose acetate and mixed cellulose esters have been shown to be suitable. Where sterile filters are not available the risks and benefits of administering unfiltered Pentostam therapy should be assessed by the clinician on an individual basis.

All dosage recommendations are based on the findings of the WHO Expert Committee on leishmaniasis which met in 1984. There are no special recommendations for different age groups.

Visceral leishmaniasis: 10 to 20 mg Sb⁵⁺ (0.1 to 0.2 ml Pentostam)/kg bodyweight to a maximum of 850 mg (8.5 ml Pentostam) daily for a minimum period of 20 days. Patients should be examined for evidence of relapse after 2 and 6 months, and in Africa after 12 months.

Cutaneous leishmaniasis NOT caused by L. aethiopica: The dosage regimen outlined for visceral leishmaniasis is recommended. Alternatively, single, non-inflamed nodular lesions known not to be due to L. braziliensis may be treated with intralesional injections of 100 to 300 mg Sb⁵⁺ (1 to 3 ml Pentostam) repeated once or twice if necessary at intervals of 1 to 2 days. Infiltration must be thorough and produce complete blanching of the base of the lesion.

Individuals with cutaneous leishmaniasis due to L. braziliensis should be treated systematically for several days after the lesion is healed.

Note: After successful treatment of L. braziliensis, anti-leishmania antibody titres decline steadily over 4 to 24 months.

Muco-cutaneous leishmaniasis: Patients with parasitologically confirmed leishmaniasis should be treated with 20 mg Sb⁵⁺ (0.2 ml Pentostam)/kg bodyweight to a maximum of 850 mg (8.5 ml Pentostam) daily, continuing this dosage for several days longer than it takes to achieve parasitological and clinical cure.

In the event of relapse, a further course should be given for at least twice the previous duration.

Diffuse cutaneous leishmaniasis in the New World and leishmaniasis recidivans: Owing to the rarity of these conditions, precise data on dosage are not available. A dose of 10 to 20 mg Sb⁵⁺ (0.1 to 0.2 ml Pentostam)/kg bodyweight to a maximum of 850 mg (8.5 ml Pentostam) may be given daily for 2 to 3 weeks. If there is a response, then treatment should be maintained until several days after clinical cure of leishmaniasis recidivans and for several months after clinical and parasitological cure of diffuse cutaneous leishmaniasis.

Use in the elderly: There is little information on the effects of Pentostam on elderly individuals. If treatment of cutaneous leishmaniasis is necessary then local infiltration is preferred. The normal precautions should be strictly adhered to when treating older patients for visceral leishmaniasis.

Pentostam should not be given to any patient with significantly impaired renal function.

Pentostam should not be given to any patient who has experienced a serious adverse reaction to a previous dose.

Intravenous injection should be filtered immediately before use (see Posology and Method of Administration). Administer very slowly over 5 minutes to reduce the risk of local thrombosis. In the unlikely event of coughing, vomiting or substernal pain occurring, administration should be discontinued immediately. In such cases, extreme care should be taken if Pentostam is re-administered by this route.

Successful treatment of mucocutaneous leishmaniasis may induce severe inflammation around the lesion. In cases of pharyngeal or tracheal involvement, this may be life-threatening. Under such circumstances, corticosteroids may be used.

Very rarely, anaphylactic shock may develop during treatment for which adrenaline injection and appropriate supportive measures should be given immediately.

Prolongation of the QTc interval has been observed in some patients taking sodium stibogluconate and appears to be dose-related. There have also been reports of fatal cardiac arrhythmias in patients receiving higher dose antimonial therapy for visceral leishmaniasis. Therefore, ECG monitoring is recommended before and during therapy with sodium stibogluconate. Where ECG monitoring is not available, the risks and benefits of sodium stibogluconate therapy should be assessed on an individual basis.

If clinically significant prolongation of QTc interval occurs, sodium stibogluconate should be discontinued. Electrocardiographic changes, notably alterations in T wave amplitude may be expected in the majority of patients given sodium stibogluconate, these appear to be reversible on cessation of therapy and are not of serious significance.

Sodium stibogluconate should be used with caution in patients with cardiovascular disease, a history of ventricular arrhythmias or other risk factors known to predispose towards QT prolongation: for example, those with congenital QTc prolongation or taking concomitant drugs known to significantly prolong the QT interval (e.g. class III anti-arrhythmics such as sotalol and amiodarone).

As there appears to be a dose relationship in the development of ECG abnormalities, prior exposure to antimonial therapy should be considered when assessing a patient's suitability for initiating or continuing therapy with sodium stibogluconate.

Patients who have recently received other antimonial drugs should be monitored closely for signs of antimony intoxication such as bradycardia and cardiac arrhythmias during administration of sodium stibogluconate.

Intercurrent infections, such as pneumonia, should be sought and treated concomitantly.

High concentrations of antimony are found in the livers of animals after repeated dosage with pentavalent antimony. Pentostam should therefore be used with caution in patients with hepatic disease. However, some abnormalities of liver function may be expected in cases of visceral leishmaniasis. In such patients the benefit of pentavalent antimony treatment outweighs the risk. Pentostam may induce mild elevation of hepatic enzymes in serum which later return to normal.

The Pack for this product carries the following statements:

Keep out of the reach and sight of children

Do not store above 25^°C. Do not freeze.

Protect from light

Poison

In addition the 100 ml pack will have the following statement:

The contents should not be used more than 1 month after removing the first dose.

No interactions with Pentostam have been reported.

Although no effects on the foetus have been reported, Pentostam should be withheld during pregnancy unless the potential benefits to the patient outweigh the possible risk to the foetus.

Children should not be breast-fed by mothers receiving Pentostam.

None known.

Approximately 1 to 2% of patients complain of nausea, vomiting and/or diarrhoea and a slightly higher number of abdominal pain.

Other common side-effects include anorexia, malaise, myalgia, arthralgia headache and lethargy.

ECG changes, including reduction in T-wave amplitude, T-wave inversion and QT prolongation have been observed (see Section 4.4 Special Warnings and Precautions for Use).

Transient coughing immediately following injection was reported with varying frequency during several trials.

Intravenous injection of Pentostam may cause transient pain along the course of the vein and eventually thrombosis of that vein.

Transient rises in serum lipase and amylase usually occur during treatment with sodium stibogluconate. Symptomatic pancreatitis has also been reported.

During some early trials of sodium stibogluconate, pneumonia occurred in a small number of patients treated for visceral leishmaniasis and this occasionally proved fatal. Pneumonia is a feature of the visceral leishmaniasis disease process; however, it has been associated with the toxicity profile of trivalent antimony. It is, therefore, not possible to determine whether these cases were due to the disease or to Pentostam.

Other (rarely reported) side-effects include fever, rigor, sweating, vertigo, facial flushing, worsening of lesions on the cheek, bleeding from the nose or gum, substernal pain, jaundice and rash.

Transient reductions in platelets, white blood cells and haemoglobin.

The main symptoms of antimony overdosage are gastro-intestinal disturbances (nausea, vomiting and severe diarrhoea). Haemorrhagic nephritis and hepatitis may also occur.

There is only limited information on the use of chelating agents in the treatment of intoxication with antimony compounds. Dimercaprol has been reported to be effective: a dose of 200 mg by intramuscular injection, every six hours until recovery is complete, is suggested.

2,3-dimercaptosuccinic acid (DMSA) may also be effective treatment.

The mode of action of Pentostam is unknown. In vitro exposure of amastigotes to 500 mg Sb⁵⁺/ml results in a greater than 50% decrease in parasite DNA, RNA protein and purine nucleoside triphosphate levels. It has been postulated that the reduction in ATP (adenosine triphosphate) and GTP (guanosine triphosphate) synthesis contributes to decreased macromolecular synthesis.

Following intravenous or intramuscular administration of sodium stibogluconate, antimony is excreted rapidly via the kidneys, the majority of the dose being detected in the first 12-hour urine collection. This rapid excretion is reflected by a marked fall in serum or whole blood antimony levels to approximately 1 to 4% of the peak level by 8 hours after an intravenous dose. During daily administration, there is a slow accumulation of sodium stibogluconate into the central compartment so that tissue concentrations reach a theoretical maximum level after at least 7 days.

There are no preclinical data of relevance to the prescriber which are additional to that in other sections of the SPC.

Chlorocresol BP

Glucono-delta-lactone HSE

Water for Injections EP

None known.

36 months.

Do not store above 25^°C. Do not freeze.

Protect from light.

Amber glass vials sealed with synthetic butyl rubber closures and aluminium collars.

Pack sizes: 6 and 100ml.

Pentostam solution should be filtered immediately prior to use (see Posology and Method of Administration).

The Wellcome Foundation Ltd

Glaxo Wellcome House

Berkeley Avenue

Greenford

Middlesex

UB6 ONN

Trading as:

GlaxoSmithKline UK

Stockley Park West

Uxbridge

Middlesex UB11 1BT.

PL 0003/5105R

Renewal of the Authorisation: 12/01/2007

12/01/2007