TeSunate Injection

Description

Artemisinin is the parent compound for semisynthetic derivatives that have been chemically modified to produce artesunate, artemether, arteether, dihydroartemisinin, and artelinic acid. Artesunate for injection comes as the sodium salt of hemisuccinate ester of artemisinin. It is soluble in water but has poor stability in aqueous solution at neutral or acid pH. Artesunate injections can be given by the intramuscular or intravenous routes.

Mechanism of Action

Malarial parasites in the infected RBC consume haemoglobin. The ‘globin’ part is used as food by the parasite and iron (haem) from the haemoglobin is toxic for the parasite. So it is stored in a food vacuole after polymerization into non-toxic haemozoin (malaria pigment).

Artemisinins after absorption get concentrated in the food vacuole. The endoperoxide bridge splits the stored haemozoin and releases free radicles of iron. These free radicles of iron cause lysis of the parasite cell wall. The damage includes swelling and deformity of food vacuole membrane, nuclear membrane, and also endoplasmic reticulum and this kills the parasite.

Pharmacokinetics

Artesunate is converted within minutes to di-hydroartemisinin which has half-life of 45 minutes when given by intravenous route. Artesunate appears to have more rapid action than the other artemisinin derivatives.

Indications

Severe malaria including Cerebral Malaria

Adverse Effects

There have been few adverse effects in man. Transient heart block was noted in one out of 82 patients with Artesunate. Dose related decrease in reticulocyte count and neutrophils is also seen with Artesunate. There has been no evidence of significant toxicity in a trial involving over 4000 patients.

Contraindications

Artesunate is contraindicated in patients with hypersensitive to artemisinin derivatives.

Precautions

Adequate studies regarding safe use of artemisinin derivatives during pregnancy are not available. Artemisinin derivatives should not be used in pregnancy as primary drug for uncomplicated malaria cases but these can be used for treatment of severe or complicated P. falciparum malaria infection in patients of multiple drug resistance, if the potential benefit justifies the potential risk to foetus.

Nursing Mothers

It is not known whether Artesunate is excreted in human milk. Caution should be exercised while using Artesunate in nursing mothers.

Drug Interactions

Prolonged QT-interval has been reported in some studies with high dosage of artemisinin derivatives. The cardiac effects of artemisinins are not very important from a clinical point of view, except that caution should be exercised against combination with other drugs that prolonged the QT – interval such as quinine and halofantrine.

Dosage

2.4mg / kg body weight: at admission, then at 12 hours, 24 hrs. then once daily for 7 days or till the patient is able to take oral medication like an ACT ( TeSunate SP / Lumart )

Presentation

TeSunate is available in Injection form.

Available as TeSunate 60mg and TeSunate 120mg Injection

Each vial contains: Artesunate 60 mg The pack also contains:

1 ml ampoule of Sodium bicarbonate inj. BP 5%w/v and 5 ml ampoule of Sodium chloride inj. IP 0.9%w/v

Reconstitution for the 60 mg Injection

Step 1 –Flip off the seal of the vial add 1 ml of Sodium bicarbonate from the ampoule. Mix well for 2-3 minutes till solution is clear.

Step 2 –For IV use–Add 5 ml of Sodium chloride from the ampoule provided or of 5% glucose to make final concentration of 10 mg/ml of Artesunate, to the vial. Mix again. Inject by slow IV route over 2-3 minutes. Do not put the solution in an IV drip.

For IM use –Add 2 ml of Sodium chloride or 5% glucose to the vial to make final concentration of 20 mg/ml of Artesunate. Mix and inject by IM route.

The pack of TeSunate 120 contains

A vial containing 120 mg of Artesunate powder + 2ml ampoule of Sodium bicarbonate + 10 ml vial of Sodium chloride

Reconstitution process is same as that for 60mg vial. Except the quantities are doubled. The injection may be administered over 5 minutes.