Citizendia

Zidovudine
Systematic (IUPAC) name
1-[(2R,4S,5S)-4-azido-5-(hydroxymethyl)tetrahydrofuran-2-yl]-
5-methylpyrimidine-2,4(1H,3H)-dione
Identifiers
CAS number30516-87-1
ATC codeJ05AF01
PubChem35370
DrugBankAPRD00449
Chemical data
FormulaC10H13N5O4 
Mol. mass267. IUPAC Nomenclature is a system of naming Chemical compounds and of describing the science of Chemistry in general CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to The Anatomical Therapeutic Chemical Classification System is used for the classification of drugs It is controlled by the WHO Collaborating Centre for Drug A section of the Anatomical Therapeutic Chemical Classification System. PubChem is a Database of chemical Molecules The system is maintained by the National Center for Biotechnology Information (NCBI a component The DrugBank database available at the University of Alberta is a unique Bioinformatics and Cheminformatics resource that combines detailed drug (i A chemical formula is a way of expressing information about the Atoms that constitute a particular Chemical compound, and how the relationship between those atoms changes Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the The molecular mass (abbreviated m of a substance, more commonly referred to as molecular weight and abbreviated as MW, is the Mass of one 242 g/mol
SMILESeMolecules & PubChem
Pharmacokinetic data
Bioavailabilitynear complete absoprtion, following first-pass metabolism systemic availability 65% (range 52 to 75%)
Protein binding30 to 38%
MetabolismHepatic
Half life0. In Pharmacology, bioavailability is used to describe the fraction of an administered Dose of unchanged drug that reaches the Systemic circulation, one of A drug's efficiency may be affected by the degree to which it binds to the proteins within Blood plasma. Drug metabolism is the Metabolism of drugs, their Biochemical modification or degradation usually through specialized enzymatic systems The liver is a vital organ in the human body and is present in Vertebrates and some other animals The biological half-life of a substance is the time it takes for a substance (drug radioactive nuclide or other to lose half of its pharmacologic physiologic or radiologic activity 5 to 3 hours
ExcretionRenal
Therapeutic considerations
Pregnancy cat.

C(US)

Legal status
RoutesOral

Zidovudine (INN) or azidothymidine (AZT) (also called ZDV) is an antiretroviral drug, the first approved for treatment of HIV. Excretion is the process of eliminating waste products of Metabolism and other non-useful materials The kidneys are complicated organs that have numerous biological roles The pregnancy category of a pharmaceutical agent is an assessment of the risk of fetal injury due to the pharmaceutical if it is used as directed by the mother during The United States of America —commonly referred to as the The regulation of therapeutic goods, that is drugs and therapeutic devices, varies by jurisdiction In Pharmacology and Toxicology, a route An International Nonproprietary Name ( INN; also known as rINN, for recommended International Nonproprietary Name or pINN for proposed Human immunodeficiency virus ( HIV) is a Lentivirus (a member of the Retrovirus family that can lead to acquired immunodeficiency syndrome It is also sold under the names Retrovir and Retrovis, and as an ingredient in Combivir, Epzicom and Trizivir. Combivir is the brand name for a pharmaceutical treatment for HIV infection. Epzicom is the brand name for a pharmaceutical treatment for HIV infection. Trizivir is a fixed dose combination of three Reverse transcriptase inhibitors patented by GlaxoSmithKline: Abacavir It is an analog of thymidine. For other uses see Analog (disambiguation. In Chemistry, analogs or analogues are compounds in which one or Thymidine (more precisely called deoxythymidine; can also be labelled deoxyribosylthymine, and thymine deoxyriboside) is a Chemical compound

Contents

History

Zidovudine was the first drug approved for the treatment of AIDS and HIV infection. Jerome Horwitz of Barbara Ann Karmanos Cancer Institute and Wayne State University School of Medicine first synthesized AZT in 1964, under a US National Institutes of Health (NIH) grant. Jerome Horwitz of Barbara Ann Karmanos Cancer Institute and Wayne State University School of Medicine is an American scientist. The Wayne State University School of Medicine ( WSUSOM) is the largest single-campus Medical school in the United States The United States of America —commonly referred to as the "NIH" redirects here For other meanings of NIH see NIH (disambiguation. In the United States Federal grants are economic Aid issued by the United States government out of the general federal revenue AZT was originally intended to treat cancer, but was shelved after it proved ineffective in treating cancer in mice. Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled [1]

In February 1985, Samuel Broder, Hiroaki Mitsuya, and Robert Yarchoan, three scientists in the National Cancer Institute (NCI), collaborating with Janet Rideout and several other scientists at Burroughs Wellcome (now GlaxoSmithKline), started working on it as an AIDS drug. Samuel Broder is an Oncologist and Medical researcher. He was a co-developer of some of the first effective drugs for the treatment of AIDS and was Director Hiroaki Mitsuya (born 1950 is a Japanese Virologist famous for his role in discovery of the anti- HIV drug zidovudine ( AZT) as well as other anti-AIDS Robert Yarchoan (born 1950) is a medical researcher who played an important role in the development of the first effective drugs for AIDS. The National Cancer Institute (NCI is part of the United States Federal government's National Institutes of Health. GlaxoSmithKline plc () is a United Kingdom -based pharmaceutical, biological and Healthcare Company. After showing that this drug was an effective agent against HIV in vitro, the team conducted the initial clinical trial that provided evidence that it could increase CD4 counts in AIDS patients. In vitro ( Latin: within the glass refers to the technique of performing a given experiment in a controlled environment outside of a living Organism In health care clinical trials are conducted to allow safety and Efficacy data to be collected for new drugs or devices CD4 ( Cluster of differentiation 4 is a Glycoprotein expressed on the surface of T helper cells, Regulatory T cells, Monocytes,

A placebo-controlled randomized trial of AZT was subsequently conducted by Burroughs-Wellcome, in which it was shown that AZT could prolong the life of patients with AIDS. Placebo is a substance or procedure a patient accepts as medicine or therapy but which has no specific therapeutic activity In health care clinical trials are conducted to allow safety and Efficacy data to be collected for new drugs or devices Burroughs Wellcome Co. filed for a patent on AZT in 1985. The Food and Drug Administration (FDA) approved the drug (via the then-new FDA accelerated approval system) for use against HIV, AIDS, and AIDS Related Complex (ARC, a now-defunct medical term for pre-AIDS illness) on March 20, 1987, and then as a preventive treatment in 1990. Events 1600 - The Linköping Bloodbath takes place on Maundy Thursday in Linköping, Sweden. Year 1987 ( MCMLXXXVII) was a Common year starting on Thursday (link displays 1987 Gregorian calendar) It was initially administered in much higher dosages than today, typically 400 mg every four hours (even at night). However, the unavailability at that time of alternatives to treat AIDS affected the risk/benefit ratio, with the certain toxicity of HIV infection outweighing the risk of drug toxicity. One of AZT's side effects includes anemia, a common complaint in early trials. Anemia ( AmE) or anæmia/anaemia ( BrE) (from the Ancient Greek grc-Latn anaîmia, meaning “without blood” is defined as a qualitative

Modern treatment regimens typically use lower dosages (e. g. 300 mg) two times a day. As of 1996, AZT, like other antiretroviral drugs, is almost always used as part of highly active antiretroviral therapy (HAART). That is, it is combined with other drugs in order to prevent mutation of HIV into an AZT-resistant form. [2][3]

The crystal structure of AZT was reported by Alan Howie (Aberdeen University) in 1988. The University of Aberdeen is an Ancient university founded in 1495, in Old Aberdeen, Scotland. [4] In the solid state AZT forms a hydrogen bond network. A hydrogen bond results from a Dipole-dipole force between an Electronegative atom and a Hydrogen atom bonded to Nitrogen, Oxygen

Prophylaxis

A crystal of AZT, viewed under polarized light
A crystal of AZT, viewed under polarized light

AZT may be used in combination with other antiretroviral medications to substantially reduce the risk of HIV infection following a significant exposure to the virus (such as a needle-stick injury involving blood or body fluids from an individual known to be infected with HIV). [5]

AZT is also recommended as part of a regimen to prevent mother-to-child transmission of HIV during pregnancy, labor and delivery. Vertical transmission, also known as Mother-to-child transmission refers to transmission of an Infection, such as HIV, Hepatitis B, or Hepatitis [6] With no treatment, approximately 25% of infants whose mothers are infected with HIV will become infected. AZT has been shown to reduce this risk to approximately 8% when given in a three-part regimen during pregnancy, delivery and to the infant for 6 weeks after birth. [7] Use of appropriate combinations of antiretroviral medications and cesarean section when necessary can further reduce mother-child transmission of HIV to 1-2%. A Caesarean section (or Cesarean section in American English) also known as C-section, is a form of Childbirth in which a surgical

Side effects

Common side effects of AZT include nausea, headache, changes in body fat, and discoloration of fingernails and toenails. More severe side effects include anemia and bone marrow suppression, which can be overcome using erythropoietin or darbepoetin treatments. Anemia ( AmE) or anæmia/anaemia ( BrE) (from the Ancient Greek grc-Latn anaîmia, meaning “without blood” is defined as a qualitative Bone marrow suppression or myelotoxicity (adjective myelotoxic) is a serious side-effect of Chemotherapy and certain drugs affecting the immune system Erythropoietin (ɨˌɹɪθɹoʊˈpɔɪɨtɨn /ɨˌɹɪθɹoʊˈpɔɪtən/ or /ɨˌɹiːθɹoʊ-/ or EPO is a Glycoprotein Hormone that controls Darbepoetin alfa ( rINN) (dɑrbəˈpɔɪtɨn is a synthetic form of Erythropoietin. 23 These unwanted side effects might be caused by the sensitivity of the γ-DNA polymerase in the cell mitochondria. In Cell biology, a mitochondrion (plural mitochondria) is a membrane-enclosed Organelle found in most eukaryotic cells. AZT has been shown to work additively or synergistically with many anti-HIV agents; however, acyclovir and ribavirin decrease the antiviral effect of AZT. Aciclovir ( INN Ribavirin (Copegus Rebetol Ribasphere VilonaVirazole also generics from Sandoz Teva Warrick is an Anti-viral drug which is active against a number of DNA and Drugs that inhibit hepatic glucuronidation, such as indomethacin, acetylsalicylic acid (Aspirin) and trimethoprim, decrease the elimination rate and increase the toxicity. The liver is a vital organ in the human body and is present in Vertebrates and some other animals Glucuronic acid (from Greek γλυκερός - "sweet" is a Carboxylic acid. Indometacin ( INN Aspirin, or acetylsalicylic acid (ASA (əˌsɛtɨlsælɨˌsɪlɨk ˈæsɨd is a Salicylate drug, often used as an Analgesic to relieve Trimethoprim ( INN) (traɪˈmɛθəprɪm is a bacteriostatic Antibiotic mainly used in the Prophylaxis and treatment of Urinary tract infections [8]

Viral resistance

AZT does not destroy the HIV infection, but only delays the progression of the disease and the replication of virus, even at very high doses. During prolonged AZT treatment HIV has the ability to gain an increased resistance to AZT by mutation of the reverse transcriptase. In biology mutations are changes to the Nucleotide sequence of the Genetic material of an organism In Biochemistry, a reverse transcriptase, also known as RNA-dependent DNA polymerase, is a DNA polymerase Enzyme that transcribes A study showed that AZT could not impede the resumption of virus production, and eventually cells treated with AZT produced viruses as much as the untreated cells. So as to slow the development of resistance, it is generally recommended that AZT be given in combination with another reverse transcriptase inhibitor and an antiretroviral from another group, such as a protease inhibitor or a non-nucleoside reverse transcriptase inhibitor. Reverse transcriptase inhibitors (RTIs are a class of Antiretroviral drug used to treat HIV infection Tumors, and Cancer. Reverse transcriptase inhibitors (RTIs are a class of Antiretroviral drug used to treat HIV infection Tumors, and Cancer.

Mode of action

AZT in oral and injectable form
AZT in oral and injectable form

Like other reverse transcriptase inhibitors, AZT works by inhibiting the action of reverse transcriptase, the enzyme that HIV uses to make a DNA copy of its RNA. Reverse transcriptase inhibitors (RTIs are a class of Antiretroviral drug used to treat HIV infection Tumors, and Cancer. In Biochemistry, a reverse transcriptase, also known as RNA-dependent DNA polymerase, is a DNA polymerase Enzyme that transcribes Enzymes are Biomolecules that catalyze ( ie increase the rates of Chemical reactions Almost all enzymes are Proteins Deoxyribonucleic acid ( DNA) is a Nucleic acid that contains the genetic instructions used in the development and functioning of all known Ribonucleic acid ( RNA) is a Nucleic acid that consists of a long chain of Nucleotide units Reverse transcription is necessary for production of the viral double-stranded DNA, which is subsequently spliced into the genetic material of a target cell (where it is called a provirus). Deoxyribonucleic acid ( DNA) is a Nucleic acid that contains the genetic instructions used in the development and functioning of all known The cell is the structural and functional unit of all known living Organisms It is the smallest unit of an organism that is classified as living and is often called A provirus is a Virus genome that has integrated itself into the DNA of a host cell. [9][10][11]

The azido group increases the lipophilic nature of AZT, allowing it to cross cell membranes easily by diffusion and thereby also to cross the blood-brain barrier. Lipophilicity, fat-liking, refers to the ability of a Chemical compound to dissolve in fats oils lipids and non-polar solvents such as Hexane or The cell membrane (also called the plasma membrane, plasmalemma, or "phospholipid bilayer" is a Selectively permeable Lipid bilayer Diffusion is the net movement of particles (typically molecules from an area of high concentration to an area of low concentration by uncoordinated random movement The blood-brain barrier (BBB is a metabolic or cellular structure in the Central nervous system (CNS that restricts the passage of various chemical substances and microscopic Cellular enzymes convert AZT into the effective 5'-triphosphate form. Studies have shown that the termination of the formed DNA chains is the specific factor in the inhibitory effect.

The triphosphate form also has some ability to inhibit cellular DNA polymerase, which is used by normal cells as part of cell division. A DNA Polymerase is an Enzyme that assists in DNA replication. Cell division is a process by which a cell, called the parent cell divides into two or more cells called daughter cells. [12][13][14] However, AZT has a 100- to 300-fold greater affinity for the HIV reverse transcriptase, as compared to the human DNA polymerase, accounting for its selective antiviral activity. [15] A special kind of cellular DNA polymerase that replicates the DNA in mitochondria is relatively more sensitive to inhibition by AZT, and this accounts for certain toxicities such as damage to cardiac and other muscles (also called myositis). In Cell biology, a mitochondrion (plural mitochondria) is a membrane-enclosed Organelle found in most eukaryotic cells. Myositis is a general term for Inflammation of the Muscles Many such conditions are considered likely to be caused by Autoimmune conditions rather [16][17][18][19][20]

Patent issues

AZT has been the target of some controversy due to the nature of the patent process. [21]

In 1991, Public Citizen filed a lawsuit claiming that the AZT/Zidovudine patent was invalid. Public Citizen is a Washington DC -based public interest group engaged in Consumer Advocacy, government accountability clean democracy and ethical The United States Court of Appeals for the Federal Circuit ruled in 1992 in favour of Burroughs-Wellcome, the licensee of the patent. The United States Court of Appeals for the Federal Circuit is a United States court of appeals and was created by Congress with passage of the Federal Courts Improvement [22] The court ruled that the challenge of the citizen group was not the correct approach to evaluate the underlying validity of the patent which was already being litigated in another suit. [23] In 2002, another lawsuit was filed over the patent by the AIDS Healthcare Foundation. The AIDS Healthcare Foundation (AHF is a Non profit, Los Angeles -based global organization that provides AIDS treatment and advocacy to over 70000

However, the patent expired in 2005 (placing AZT in the public domain), allowing other drug companies to manufacture and market generic AZT without having to pay GlaxoSmithKline any royalties. A patent is a set of Exclusive rights granted by a State to an inventor or his assignee for a fixed period of time in exchange for a disclosure of an The public domain is a range of abstract materials &ndash commonly referred to as Intellectual property &ndash which are not owned or controlled by anyone GlaxoSmithKline plc () is a United Kingdom -based pharmaceutical, biological and Healthcare Company. The U. S. FDA has since approved four generic forms of AZT for sale in the U. A generic drug (generic drugs short generics is a drug which is produced and distributed without Patent protection S.

Footnotes

  1. ^ A Failure Led to Drug Against AIDS. Published in the New York Times on September 20, 1986; accessed March 17, 2008. Events 451 - The Battle of Chalons takes place in North Eastern France. Year 1986 ( MCMLXXXVI) was a Common year starting on Wednesday (link displays 1986 Gregorian calendar) Events 45 BC - In his last victory Julius Caesar defeats the Pompeian forces of Titus Labienus and Pompey the Younger 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common
  2. ^ De Clercq E (1994). "HIV resistance to reverse transcriptase inhibitors. ". Biochem Pharmacol 47 (2): 155-69. PMID 7508227.  
  3. ^ Yarchoan R, Mitsuya H, Broder S (1988). "AIDS therapies. ". Sci Am 259 (4): 110-9. PMID 3072667.  
  4. ^ Dr. Alan Howie. Dr Alan Howie. University of Aberdeen. Retrieved on 2006-01-18. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 350 - Generallus Magnentius deposes Roman Emperor Constans and proclaims himself Emperor
  5. ^ Updated U.S. Public Health Service Guidelines for the Management of Occupational Exposures to HIV. Retrieved on 2006-03-29. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 1461 - Wars of the Roses: Battle of Towton - Edward of York defeats Queen Margaret to become King
  6. ^ Recommendations for Use of Antiretroviral Drugs in Pregnant HIV-1-Infected Women for Maternal Health. Retrieved on 2006-03-29. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 1461 - Wars of the Roses: Battle of Towton - Edward of York defeats Queen Margaret to become King
  7. ^ Connor E, Sperling R, Gelber R, Kiselev P, Scott G, O'Sullivan M, VanDyke R, Bey M, Shearer W, Jacobson R (1994). "Reduction of maternal-infant transmission of human immunodeficiency virus type 1 with zidovudine treatment. Pediatric AIDS Clinical Trials Group Protocol 076 Study Group. ". N Engl J Med 331 (18): 1173-80. PMID 7935654.  
  8. ^ ZIDOVUDINE (AZT) - ORAL (Retrovir) side effects, medical uses, and drug interactions. MedicineNet. Retrieved on 2006-01-09. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 475 - Byzantine Emperor Zeno is forced to flee his capital at Constantinople.
  9. ^ Mitsuya H, Yarchoan R, Broder S (1990). "Molecular targets for AIDS therapy. ". Science 249 (4976): 1533-44. doi:10.1126/science.1699273. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. PMID 1699273.  
  10. ^ Mitsuya H, Weinhold K, Furman P, St Clair M, Lehrman S, Gallo R, Bolognesi D, Barry D, Broder S (1985). "3'-Azido-3'-deoxythymidine (BW A509U): an antiviral agent that inhibits the infectivity and cytopathic effect of human T-lymphotropic virus type III/lymphadenopathy-associated virus in vitro.". Proc Natl Acad Sci U S A 82 (20): 7096-100. doi:10.1073/pnas.82.20.7096. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. PMID 2413459.  
  11. ^ Yarchoan R, Klecker R, Weinhold K, Markham P, Lyerly H, Durack D, Gelmann E, Lehrman S, Blum R, Barry D (1986). "Administration of 3'-azido-3'-deoxythymidine, an inhibitor of HTLV-III/LAV replication, to patients with AIDS or AIDS-related complex. ". Lancet 1 (8481): 575-80. PMID 2869302.  
  12. ^ Furman P, Fyfe J, St Clair M, Weinhold K, Rideout J, Freeman G, Lehrman S, Bolognesi D, Broder S, Mitsuya H (1986). "Phosphorylation of 3'-azido-3'-deoxythymidine and selective interaction of the 5'-triphosphate with human immunodeficiency virus reverse transcriptase. ". Proc Natl Acad Sci U S A 83 (21): 8333-7. doi:10.1073/pnas.83.21.8333. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. PMID 2430286.  
  13. ^ Mitsuya H, Weinhold K, Furman P, St Clair M, Lehrman S, Gallo R, Bolognesi D, Barry D, Broder S (1985). "3'-Azido-3'-deoxythymidine (BW A509U): an antiviral agent that inhibits the infectivity and cytopathic effect of human T-lymphotropic virus type III/lymphadenopathy-associated virus in vitro. ". Proc Natl Acad Sci U S A 82 (20): 7096-100. doi:10.1073/pnas.82.20.7096. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. PMID 2413459.  
  14. ^ Plessinger M, Miller R. "Effects of zidovudine (AZT) and dideoxyinosine (ddI) on human trophoblast cells. ". Reprod Toxicol 13 (6): 537-46. PMID 10613402.  
  15. ^ Mitsuya H, Weinhold KJ, Furman PA, et al: 3'-azido-3;-deoxythymidine (BW A509U): an antiviral agent that inhibits the infectivity and cytopathic effect of human T-lymphotropic virus type III/lymphadenopathy-associated virus in vitro. Med Sci 1985; 82:7096-7100.
  16. ^ Collins M, Sondel N, Cesar D, Hellerstein M (2004). "Effect of nucleoside reverse transcriptase inhibitors on mitochondrial DNA synthesis in rats and humans. ". J Acquir Immune Defic Syndr 37 (1): 1132-9. PMID 15319672.  
  17. ^ Parker W, White E, Shaddix S, Ross L, Buckheit R, Germany J, Secrist J, Vince R, Shannon W (1991). "Mechanism of inhibition of human immunodeficiency virus type 1 reverse transcriptase and human DNA polymerases alpha, beta, and gamma by the 5'-triphosphates of carbovir, 3'-azido-3'-deoxythymidine, 2',3'-dideoxyguanosine and 3'-deoxythymidine. A novel RNA template for the evaluation of antiretroviral drugs. ". J Biol Chem 266 (3): 1754-62. PMID 1703154.  
  18. ^ Rang H. P. , Dale M. M. , Ritter J. M. (1995). Pharmacology, 3rd edition, Pearson Professional Ltd.  
  19. ^ Balzarini J, Naesens L, Aquaro S, Knispel T, Perno C, De Clercq E, Meier C (1999). "Intracellular metabolism of CycloSaligenyl 3'-azido-2', 3'-dideoxythymidine monophosphate, a prodrug of 3'-azido-2', 3'-dideoxythymidine (zidovudine).". Mol Pharmacol 56 (6): 1354-61. PMID 10570065.  
  20. ^ Yarchoan R, Mitsuya H, Myers C, Broder S (1989). "Clinical pharmacology of 3'-azido-2',3'-dideoxythymidine (zidovudine) and related dideoxynucleosides. ". N Engl J Med 321 (11): 726-38. PMID 2671731.  
  21. ^ The Best Democracy Money Can Buy by Greg Palast (2002)
  22. ^ People with Aids Health Group v. The Best Democracy Money Can Buy (first published in 2002 by Pluto Press London ISBN 0-452-28391-4 Penguin Plume USA) is a 2002 Book written Gregory Allyn Palast (born 1952 is a New York Times -bestselling author and a journalist for the British Broadcasting Corporation as well as Burroughs Wellcome Co. , 1992 U. S. Dist. LEXIS 578
  23. ^ US Court of Appeals for the Federal Circuit. Burroughs Wellcome Co. v. Barr Laboratories, 40 F.3d 1223 (Fed. Cir. 1994). University of Houston -- Health Law and Policy Institute. Retrieved on 2007-02-28. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 202 BC - coronation ceremony of Liu Bang as Emperor Gaozu of Han takes place initiating four centuries of the Han Dynasty 's rule

Dictionary

zidovudine

-noun

  1. A nucleoside analog reverse transcriptase inhibitor, a type of antiretroviral drug, the first approved treatment for HIV.
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