Artesunate for Injection
1. NAME OF THE MEDICINAL PRODUCT
2. QUALITATIVE AND QUANTITATIVE COMPOSITION
Each Artesun 30mg box contains 1 vial of 30mg artesunate powder for solution for injection, 1 ampoule of 0.5 ml sodium bicarbonate 50 mg/ml solution for injection and 1 ampoule of 2.5mi sodium chloride 9mg/mi solution for injection.
Each Artesun 60mg box contains 1 vial of 60 mg artesunate powder for solution for injection, 1 ampoule of 1 ml sodium bicarbonate 50mg/ml solution for injection and 1 ampoule of 5 ml sodium chloride 9mg/ml solution for injection.
Each Artesun 120mg box contains 1 vial of 120mg artesunate powder for solution for injection, 1 ampoule of 2 ml sodium bicarbonate 50mg/ml solution for injection and 1 ampoule of 10 ml sodium chloride 9 mg/ml solution for injection.
3. PHARMACEUTICAL FORM
Artesunate for injection: White crystalline powder
Solvent (sodium bicarbonate injection): Clear, colourless liquid
Solvent (sodium chloride injection): Clear, colourless liquid
4. CLINICAL PARTICULARS
4.1 Therapeutic indication
Artesun, administered intravenously or intramuscularly, is indicated for the treatment of severe malaria caused by Plasmodium falciparum, in adults and children.
4.2 Posology and method of administration
Adults and children weighing 20kg or more: Artesun is administered at a dose of 2.4 mg of artesunate / kg body weight by intravenous (IV) or intramuscular (IM) injection, at 0.12 and 24 hours, then once daily until oral treatment can be substituted.
Children weighing less than 20 kg: Artesun is administered at a dose of 3 mg of artesunate / kg body weight, by intravenous (IV) or intramuscular (IM) injection, at 0.12 and 24 hours, then once daily until oral treatment can be substituted (see section 5.1).
Method of administration
Artesun should be administered for a minimum of 24 hours (3 doses), regardless of the patient’s ability to tolerate oral medication earlier. After at least 24 hours of Artesun, and when able to tolerate oral medication, the patient should be switched to a complete treatment course of an oral combination antimalarial regimen.
Because of the instability of artesunate in aqueous solutions the reconstituted solution must be used within one hour of preparation. Therefore the required dose of artesunate should be calculated and the number of vials of artesunate needed should be determined prior to reconstitution of the artesunate powder.
Reconstitution of the artesunate solution
Using a syringe, withdraw the supplied sodium bicarbonate solvent from the ampoule and inject into the vial containing the artesunate powder. Shake the vial for several minutes to mix well until the powder is completely dissolved and the solution is clear. If the solution appears cloudy or a precipitate is present, it should be discarded. The reconstituted artesunate solution should always be used immediately, and discarded if not used within one hour.
Following reconstitution the solution must be diluted according to the method of injection, as described below.
For intravenous (IV) injection
Using a syringe, add the supplied sodium chloride 0.9% for injection solvent to the vial containing the reconstituted artesunate solution. This will yield a solution containing artesunate 10 mg/ml. Shake to mix well, ensuring that the resulting solution is still clear, if the solution appears cloudy or a precipitate is present, it should be discarded.
The volume required will be equal to: (desired dose in mg)/10 ml
Withdraw the required volume of artesunate solution from the vial with a syringe and then inject slowly intravenously, over 1-2 minutes.
Artesun should NOT be administered as an intravenous drip.
For intramuscular (IM) injection
Using a syringe, add to the vial containing the reconstituted artesunate solution the following volume of the supplied sodium chloride 0.9% for injection solvent: 1 ml for Artenun 30mg, 2 ml for Artesun 60mg or 4 ml for Artesun 120mg. This will yield a solution containing artesunate 20 mg/ml. Shake to mix well, ensuring that the resulting solution is still clear. If the solution appears cloudy or a precipitate is present, it should be discarded.
The volume required will be equal to: (desired dose in mg)/20 ml.
Withdraw the required volume of artesunate solution from the vial with a syringe and then inject intramuscularly; the anterior thigh is usually the preferred site for injection. If the total volume of solution to be injected intramuscularly is large, it may be preferable to divide the volume and inject it at several sites, e.g. both thighs. Do not use water for injection for reconstitution of the artesunate powder or for dilution of the resulting solution prior to injection.
Hepatic and renal impairment
Dose adjustment is not necessary in patients with hepatic or renal impairment (see Sections 4.4 and 5.2).
Artesun is contraindicated in patients with hypersensitivity to artesunate or other artemisinins.
4.4 Special warnings and precautions for use
Artesunate has not been evaluated in the treatment of severe malaria due to Plasmodium vivax, Plasmodium malariae or Plaornodiam ovale.
Resistance to antimalarials
Local information on the prevalence of resistance to antimalarials should be considered in choosing the appropriate combination antimalarial regimen for use with Artesun (see sections 4.2).
Post-treatment haemolytic anaemia
Delayed haemolytic anaemia following treatment with injectable artesunate has been observed in children in malaria endemic areas and in non-immune travellers presenting with severe faiciparum malaria. The risk was most pronounced in patients with hyperparasitaemia and in younger children. Some cases have been severe and required blood transfusion. Vigilance for delayed onset anaemia is therefore advised, particularly in hyperparasitamic patients and younger children, and prolonged follow-up should be considered (e.g. 14-28 days).
Data regarding artesunate pharmacokinetics in patients with hepatic and/or renal impairment are limited. Based on data from studies in patients with severe malaria, as well as the known metabolism of artesunate (see Section 5.2), dosage adjustment is not considered necessary in patients with hepatic or renal impairment.
In clinical trials, the efficacy and safety of intravenous and intramuscular artesunate have been similar in adult and paediatric populations.
There is no clinical data available for infants weighing below 5kg and adults weighing over 100kg.
4.5 Interaction with other medicinal products and other forms of interaction
Artesunate is rapidly and extensively converted to dihydroartemisinin (DHA), the active metabolite, primarily by plasma and erythrocyte esterases. DHA elimination is also rapid (half-life approximately 45 min) and the potential for drug-drug interactions appears limited. In ultra drug-interaction studies have demonstrated minimal effects of artesunate on cytochrome P450 isoenzymes. Few clinical drug-drug interaction studies have been performed, however no clinically significant interactions have been identified.
4.6 Pregnancy and lactation
Severe malaria is especially hazardous during pregnancy, therefore full dose parenteral artesunate treatment should be administered at any stage of pregnancy without delay, in animal studies, artesunate has been associated with fetal toxicity during the first trimester of pregnancy. Limited clinical experience with the use of artesunate in the first trimester of pregnancy as well as clinical data from more than 2,500 pregnant women, predominantly treated with artesunate in the second and third trimester, do not indicate adverse effects of artesunate on pregnancy or on the health of the fetus/newborn child.
Limited information indicates that dihydroartemisinin, the active metabolite of artesunate, is present at low levels in breast milk. The drug levels are not expected to cause any adverse effects in breastfed infants. The amount of drug present in breast milk does not protect the infant from malaria.
4.7 Effects on ability to drive and use of machines
There is no information on the effect of artesunate on the ability to drive or use machines. The patient’s clinical status should be considered when assessing ability to drive or operate machinery.
4.8 Undesirable effects
The most important reported side effect of artesunate is a rare severe allergic reaction (estimated risk approximately 1 in 3000 patients), which has involved urticarial rash as well as other symptoms, including hypotension, pruritus, oedema, and/or dyspnoea.
More common minor side effects associated with IV administration have included dizziness, light-headedness, rash, and taste alteration (metallic/ bitter taste). Nausea, vomiting, anorexia and diarrhea have also been reported, however it is uncertain whether such events have been symptoms of severe malaria. Adverse events considered at least possibly related to artesunate are listed below by body system, organ class and absolute frequency. Frequencies are defined as very common (≥1/10), common (1/100-1/10), uncommon (1/1000-1/100), rare (1/10000-l/1000), and very rare (< 1/10000).
Blood and lymphatic systems disorders
Uncommon: Neutropenia and anaemia (both occasionally severe), thrombocytopenia
Very rare: Pure red cell aplasia
Frequency unknown: Post-treatment anaemia (see below), mild and transient decrease in reticulocyte count
Nervous system disorders
Common: Dizziness, light-headedness, headache, insomnia, tinnitus (with or without decrease in auditory function)
Very rare: Peripheral neuropathy (or paraesthesia)
Common: Cough, nasal symptoms
Common: Altered taste, nausea, vomiting, abdominal pain or cramps, diarrhoea
Rare: Raised serum amylase, pancreatitis
Uncommon: Transient rises in liver transaminases (AST, ALT)
Skin and subcutaneous tissue disorders
Common: Rash, alopecia
Musculoskeletal and connective tissue disorders
Common: Arthralgia, muscle disorders
General disorders and administration site conditions
Common: Fatigue, malaise, fever, pain at injection site
Immune system disorders
Cases of delayed haemolytic anaemia have been identified in non-immune travellers following treatment of severe malaria with injectable artesunate. Some were severe and required blood transfusions. In a study in African children aged 6 months to 10 years of age in malaria endemic areas, 5 out of 72 children (7%) experienced delayed haemolytic anaemia following treatment with injectable artesunate, and one child required transfusion, Risk was increased with hyperparasitaemia in all age groups and with younger age in children. Onset of haemolysis and anaemia was evident by 14-28 days after artesunate treatment. Vigilance for this adverse event is advised (see section 4.4)
The safety profile of injectable artesunate is similar in children and adults.
Experience of acute overdose with artesunate is limited. A case of overdose has been documented in a 5-year-old child who was inadvertently administered rectal artesunate at a dose of 88 mg/kg/day over 4 days, representing a dose more than 7-fold higher than the highest recommended artesunate dose. The overdose was associated with pancytopenia, melena, seizures, multiorgan failure and death.
Treatment of overdose should consist of general supportive measures.
5. PHARMACOLOGICAL PROPERTIES
5.1 Pharmacodynamic properties
Pharmacotherapeutic group: Antimalarial , ATC code: P01BE03
Mechanism of action
Artesunate is a hemisuccinate derivative of dihydroartemisinin, which is itself formed by the reduction of artemisinin. Artemisinin is a sesquiterpene lactone endoperoxide extracted from qinghao (sweet wormwood, Artemisia annua L), a plant which has been used for centuries in traditional Chinese medicine.
The mechanism of action of the artemisinins likely involves cleavage of the internal endoperoxide bridge through reaction with haeme within the infected erythrocyte, thereby generating free radicals which alkylate vital parasite proteins. However, artemisinins have also been reported to inhibit an essential parasite calcium adenosine triphosphatase.
The artemisinins are distinguished from other antimalarials by their ability to kill all erythrocytic stages of the malaria parasite, including the relatively inactive ring stage and late schizonts, as well as the gametocytes responsible for malaria transmission.
Artesunate and the artemisinins are the most rapid acting of the antimalarials, and they have also been shown to enhance splenic clearance of infected erythrocytes by reducing cytoadherence.
In vitro, dihydroartemisinin (DHA), the active metabolite of artesunate, exhibits similar potency against chloroquine-resistant and chloroquine-sensitive clones of P. falciparum.
Artesunate and the other artemisinins are essentially inactive against extra-erythrocytic forms, sporozoites, liver schizontes or merozoites.
Clinical efficacy and safety
In the SEAQUAMAT (South East Asian Quinine Artesunate Malaria Trial), an international randomised, open-label, multicenter trial conducted in Bangladesh, India, Indonesia and Myanmar, 1461 patients with severe malaria (including 1259 adults) were treated intravenously with either artesunate or quinine. Artesunate was administered at 2.4 mg/kg IV at 5, 12 and 24 h and then every 24 h until the patient could tolerate oral medication. Quinine was given IV at 20 mg/kg over 4 hours, followed by 10 mg/kg over 2-8 hours, 3 times daily until oral therapy could be started. Mortality in the artesunate group was 15% versus 22% in the quinine group, for a reduction in risk of death of 34.7% (p=0.0002). Subgroup analysis suggested a greater benefit of artesunate versus quinine in patients with parisitemia >10%. The reduction in mortality observed in the 202 paediatric patients (<15 years of age) appeared consistent with the overall results, however the number of children was too small to demonstrate statistical significance. Post-treatment hypoglycaemia was more common in the quinine-treated group.
The AQUAMAT (African Quinine Artesunate Malaria Trial) was an international, randomized open-label multicenter trial which sought to extend the results of the SEAQUAMAT study by comparing parenteral artesunate versus IV quinine for severe malaria in 5425 African children (< 15 years) in 9 African countries (Mozambique, The Gambia, Ghana, Kenya, Tanzania, Nigeria, Uganda, Rwanda, and Democratic Republic of the Congo). Dosing was similar to SEAQUAMAT, except that both artesunate and quinine could be administered either intravenously or intramuscularly, using the same doses for IM and IV administration for each drug. Roughly one third of patients received study drug by intramuscular injection. Mortality in the artesunate group was 8.5% compared to 10.9% in the quinine group, resulting in a relative risk reduction for death of 22.5% (p=0.0022); the risk reduction was similar for IV and IM administration. In addition, although the risk of neurological sequelae in survivors in both groups did not differ significantly by 28 days following treatment, in-hospital coma, convulsions, and deterioration of coma were all less frequent in the artesunate-treated patients. As in the SEAQUAMAT, post-treatment hypoglycaemia was more common in the quinine-treated group.
5.2 Pharmacokinetic properties
After intravenous injection artesunate is very rapidly biotransformed to its active metabolite, dihydroartemisinin (DHA). Consequently, artesunate half-life (t½) is estimated to be less than 5 minutes. Following a single IV dose of 2.4 mg/kg, maximum artesunate plasma concentrations (Cmax) were estimated to be 77 µmo//L in a study in Gabonese children with severe malaria, and 42 and 36 µmol/L in two studies in Vietnamese adults with uncomplicated malaria.
High concentrations of DHA are observed within 5 minutes of artesunate IV administration. In the above studies (adult and paediatric), the ranges of values for the estimated time to maximum concentration (tmax) and t½ for DHA were 0.5-15 minutes and 21-64 minutes, respectively, while DHA Cmax values ranged from 5.3-10.6 µmol/L.
Artesunate is rapidly absorbed following intramuscular injection, and peak plasma levels are generally achieved within 30 minutes of administration. Thus, after IM injection of 2.4 mg/kg of artesunate, absorption was rapid in Gabonnse children and Vietnamese adults, with Tmax values of 8 and 12 minutes, respectively. The corresponding artesunate t½ values were estimated to be 48 minutes in children and 41 minutes in adults, and Cmax values were 1.7 and 2.3µmol/L, for children and adults, respectively.
After IM injection artesunate Cmax values were therefore lower by roughly 45-fold in children and 20-fold in adults when compared to IV injection. However, rates of artesunate elimination in children and adults were 32-fold and 13-fold slower, respectively, following IM injection, compared to IV administration.
DHA has been shown to substantially accumulate in P. falciparum-infected erythrocytes. Plasma protein binding of dihydroartemisinin was determined to be 93% in patients and 88% in healthy volunteers.
Metabolism and elimination
Artesunate is extensively and rapidly hydrolysed by plasma esterases, with possible minimal contribution by CYP2A6. The main metabolite, dihydroartemisinin, accounts for most of the in viva antimalarial activity of oral artesunate, however, following IV administration, artesunate may contribute more significantly. DHA is further metabolized in the liver via glucuronidation and is excreted in the urine; ᾳ-dihydroartemisinin-β-glucuronide has been identified as the major urinary product in patients with falciparum malaria.
No pharmacokinetic data are available for patients with impaired renal or hepatic function. However, based on the known mechanisms of metabolism and elimination of artesunate, combined with clinical data from patients with severe malaria and accompanying renal and/or hepatic compromise of various degrees, no dose modifications are considered necessary in renal or hepatic impairment.
5.3 Preclinical safety data
Artesunate presents low acute toxicity. After repeated administration of 50 mg/kg/day in rats and 82.5 mg/kg/day in dogs, i.e. approximately 10 and 17 times the proposed maximal therapeutic dose in man, evidence of toxicity was observed in the haematopoietic organs, the immune system and response, the liver and kidneys.
Artesunate did not show any mutagenic or clastogenic potential in in vitro and in viva tests (Ames, mouse micronucleus).
No studies of the carcinogenic potential of artesunate have been conducted.
Reproductive toxicology studies
Oral artesunate caused dose-dependent foetal toxicity in rats, rabbits and monkeys, resulting in foetal resorption and abortion, as well as a low incidence of cardiac and skeletal defects. The no-observed-adverse-effect-level (NOAEL( was 12 mg/kg in pregnant monkeys (3 and 7 day exposures) and the no or low adverse effects level was 5-7 mg/kg in pregnant rats or rabbits (12 day exposures), both of which are above the therapeutic dose range (2.4-4.8 mg/kg) and expected duration of exposure for treatment of severe malaria in humans. In rats, the embryo-fetuses were most sensitive from gestational days 9-14; at other times embryotoxicity was significantly reduced.
Safety pharmacology studies
A slight sedative effect, decrease in body temperature, mild natriuresic effect and a decrease in creatinine clearance were observed with artesunate after single intravenous doses of 200 mg/kg (mice), 450 mg/kg (rats, rabbits and dogs) and following single oral doses of 180 mg/kg in male rats. Beagle dogs administered IV artesunate at 10, 20, 50, and 50 mg/kg for 14 days did not display significant clinical effects, including any signs of neurotoxicity, effects on body weight, ECG abnormalities (including QT interval changes), heart rate, blood pressure, or respiratory rate.
6. PHARMACEUTICAL PARTICULARS
6.1 List of excipients
Solvent: sodium bicarbonate
Diluent: sodium chloride
In the absence of compatibility studies, this medicinal product must not be mixed with other medicinal products.
6.3 Shelf life
6.4 Special precautions for storage
Store below 30oC. Protect from light.
The reconstituted solution should be stored below 30oC and should be used within 1 hour.
6.5 Nature and contents of container
Artesunate for injection: The primary packs are colourless, type I glass vials with gray colored type I rubber stoppers and aluminium lid with a blue flip-off plastic cover.
Solvent (sodium bicarbonate injection 50mg/ml): The primary packs are colourless type I glass ampoules.
Diluent (sodium chloride injection 9mg/ml): The primary packs are colourless type I glass ampoules.
Pack size: A small box containing one vial of artesunate for injection, one ampoule of the sodium bicarbonate injection (solvent) and one ampoule of the sodium chloride injection (diluents).
6.6 Special precautions for disposal
No special requirements
Guilin Pharmaceutical Co., Ltd.,
No.43 Qilidian Road, Guilin 541004, Guangxi, China.
8. DATE OF REVISION OF THE TEXT