a. Pharmacologicals
This medication is an antiviral preparation, have an immunomodulating and anti-influenza effect, especially anti-influenza group A and B and Severe Acute Respiratory Syndrome (SARS). It prevents contact and entry of the virus into cells by inhibiting the fusion of the viral lipid membrane with cell membrane. It has an interferon-inducing action, stimulate humoral and cell-mediated immunity, helps the phagocytic action of macrophages, and heightens the body’s ability to fight infection. It decrease the frequency of complications associated with viral infections, and lessens the consequence of chronic bacterial illnesses.
In viral infections, its therapeutic effectiveness is seen in a lowering of toxicity, lessening of clinical symptoms, and decrease in duration of the disease
Arbidol is in the category of least toxic drug (LD50 > 4g/kg). It has no negative side effect on the human body when taken orally at the recommended dosages
b. Pharmacokinetics:
Arbidol is absorbed quickly and spreads to organs and tissues. The peak blood concentrations after taking a 50 mg dose occurs 1.2 hours after administration; for a 100 mg dose, 1.5 hours after administration.
Arbidol is metabolized in the liver. The half-life of the drug in the body is about 17-21 hours. About 40% is excreted in unchanged form, mostly through bile (38.9%) and an insignificant amount through the kidneys (0.12%). Within the first 24 hours after administration, about 90% of drug has left the body.
c. Indications:
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The drug is indicated for the prevention and treatment in adults and children in the following cases:
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Influenza A due to viruses type A/H1N1, H5N1.
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Influenza B.
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Severe Acute Respiratory Syndrome (SARS).
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Secondary immunodeficiency.
d. Dosage and Administrations
Directions for use:
For internal use, to be taken on an empty stomach.
Dosage:
* Normal single dose:
- Children over 12 years - adults: Taken 200 mg / day.
- Children 6-12 years: Taken 100 mg / day.
- Children 3-6 years: Taken 50 mg / day.
* Prophylaxis (in cases of non- specific):
During direct contact with patients infected with influenza A/H1N1, doses as follows:
- Children over 12 years - adults: 200 mg / time, once a day, in 10-14 days.
- Children 6-12 years: Taken 100mg - 200 mg / time, twice in 7 days.
- Children 3-6 years: Taken 50 mg / time, twice in 7 days.
For Severe Acute Respiratory Syndrome (SARS) prophylaxis : during contact with SARS patients, doses as follows:
- Children over 12 years - adults: Taken 200 mg / time, once a day, in 12-14 days.
- Children 6-12 years: Taken 100mg / time, once a day, in 12-14 days.
* Treatment:
Treatment of influenza A/H1N1:
- Children over 12 years - adult: Taken 200 mg / time, 4 times per day, distance is 6 hours, in 7-10 days.
- Children 6-12 years: Taken 100 mg / time, 3 times per day, in 3 days.
Treatment for Severe Acute Respiratory Syndrome (SARS):
- Children over 12 years - adults: 200 mg / time , twice per day, in 8 -10 days.
e. Arbidol safety and tolerability.
· The animal study has demonstrated Arbidol (Fludon H1) low toxicity upon a single-dose; experiment with long-term, it was shown that in therapeutic doses Arbidol (Fludon H1) possessed no mutagenic or teratogenic activity.(5)
· The safety and tolerability of Arbidol (Fludon H1) had also been evaluated in a placebo-controlled study on healthy volunteer and patients with daily oral administration about 20 -25 days. The physical and biochemical examination of main organs and systems did not reveal any significant differences between ARB-treated and control groups indicating good tolerability and safety of Arbidol in humans (5);
f. Resistantance Arbidol:
· In 160 independent clinical studies from 2002 to 2005 on the viruses A and B influenza strains had shown all the experimental strains are sensitive with Arbidol (Fludon H1) (6)
· Statistics on clinical practice during15 years with Arbidol (Fludon H1) haven’t detected yet one cases of virus resistant with Arbidol (Fludon H1) (6);
REFERENCES:
1. http://www.who.int/csr/disease/swineflu/en/
2. www.cimsi.org.vn;
3. Hong Anh, Influenza H1N1 consume over 790 billion VND budgetary money, http://www.vnexpress.net/GL/Kinh-doanh/2009/11/3BA15435/
4. WHO: Influenza A (H1N1) virus resistance to Oseltamivir – 2008/2009 influenza season, Northern Hemisphere (18 March 2009). http://www.who.int/csr/disease/influenza/H1N120081230.pdf
5. Y.S. Boriskin1, I. A. Leneva2, E.-I. Pécheur3 and S. J. Polyak, Arbidol: A Broad-Spectrum Antiviral Compound that Blocks Viral Fusion, Current Medicinal Chemistry, 2008, 15(10):997-1005.
6. Burtseva, EI; Shevchenko, E.S.; Leneva I.A.; Merkulova, L.N.; Oskerko, T.A.; Shliapnikova, O.V.; Zaplatnikov, A.L.; Shuster, A.M.; Slepushkin,
A.N. Probl. Virol. (Russian), 2007, 52, 24.
7. Website của Tổ chức Y Tế thế giới tại Việt Nam: http://www.un.org.vn/who/avian/FAQ/General/question1v.htm