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ANTIMALARIAL THERAPY. Presented By: Payal Mondal Priyadarshini . K. Prachi Gaikwad Pratik Gada Parvez Shaifi CRANFIELD BATCH No.8. CONTENTS. INTRODUCTION VECTORS LIFECYCLE OF PLASMODIUM SIGNS AND SYMPTOMS DIAGNOSIS ANTIMALARIAL THERAPY RECENT ADVANCES CASE STUDY
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ANTIMALARIAL THERAPY Presented By: PayalMondal Priyadarshini. K. PrachiGaikwad PratikGada ParvezShaifi CRANFIELD BATCH No.8
CONTENTS • INTRODUCTION • VECTORS • LIFECYCLE OF PLASMODIUM • SIGNS AND SYMPTOMS • DIAGNOSIS • ANTIMALARIAL THERAPY • RECENT ADVANCES • CASE STUDY • CLINICAL TRIAL OF ANTI MALARIAL DRUG
INTRODUCTION • Malaria has been known since time immemorial, but previously it was thought that "miasma" (bad air or gas from swamps - "mal air ia") caused the disease. • Systematic control of malaria started after the discovery malaria parasite by Laveran in 1889 (for which he received the Nobel Prize for medicine in 1907) • The demonstration by Ross in 1897 that the mosquito was the vector of malaria.
MALARIA One of the most important infectious diseases in world. Caused by a parasite protozoan called Plasmodium. Four types:- Plasmodium vivax Plasmodium ovale Plasmodium malariae Plasmodium falciparum Plasmodium knowlesiis now established as the fifth Plasmodium species to cause malaria in humans (seen in Thailand and Sweden) electron micrograph of Plasmodium falciparum
VECTORS The parasite's primary (definitive) hosts and transmission vectors are female mosquitoes of the Anopheles genus, while humans and other vertebrates are secondary hosts. Plasmodiumfalciparum, a species most likely to be transmitted by the mosquito Anophelesgambiae. A. gambiae complex is the chief vector in Africa and A. freeborniin N. America.
SIGNS AND SYMPTOMS Depends on : • the parasitemia, • the presence of the organism in different organs • the parasite burden • incubation period varies generally between 10-30 days • headache, vague pains in the bones and joints, chilly sensations and fever. • chill and fever follow a cyclic pattern (paroxysm) • paroxysm is due to the rupture of infected erythrocytes and release of parasites.
DIAGNOSIS • Diagnosis is based on symptoms and detection of parasite in Giemsa stained blood smears • CBC • Electrolytes
DIAGNOSIS Plasmodium falciparum ring trophs in a single red blood cell from a human blood smear. Note the size of the infected cell RBC compared with the uninfected RBC.
Objectives & Use of Antimalarials • To prevent and treat clinical attack of malaria. • To completely eradicate the parasite from the patients body. • To reduce the human reservoir of infection- cut down transmission to mosquito. ANTIMALARIAL THERAPY: • Causal prophylaxis (Pre-erythrocytic stage in liver) • Suppressive prophylaxis(Erythrocytic phase) • Clinical cure (Erythrocyticschizontocides) • Radical Cure.(Hypnozoites + Erythrocyticschizonts) • Suppressive Cure • Gametocidal.
Classification of Antimalarial drugs • 4-Aminoquinolines– Chloroquine , Amodiaquine. • Quinoline methanol –Mefloquine. • Acridine –Mepacrine. (Atarbrine,Quinacrine) • Cinchona alkaloid–Quinine. • Biguanides –Proguanil. (chloroguanide) • Diaminopyrimidines–Pyrimethamine.
8-Aminoquinolines–Primaquine, Bulaquine. Sulfonamides & sulfones–Sulfadoxine, Sulfamethopyrazine, Dapsone. Tetracyclines –Tetracycline, Doxycycline. Sesquiterpine lactones–Artesunate, Artemether , Arteether. Phenanthrene methanol–Halofantrine. Naphthoquinone –Atovaquone.
Chloroquine • Rapidly acting erythrocyticschizonticide • Acts on all species of Plasmodium MOA: Actively concentrated by sensitive intraerythrocytic plasmodia: higher concentration in infected RBC increase vesicular pH degradation of Hb by parasitic lysosomes Inhibition of conversion of heme to hemozoin by formation of Chloroquinheme complex damage of plasmodial membrane. Quinine, mefloquine, mepacrine acts in an same manner.
Aritimisinin derivatives • Active principle of plant Artemisia annua. • Used in chinese traditional medicines. • Active against P. falciparum. • Rapidly acting blood schizontocide MOA: Endoperoxide bridge in molecule interacts with heme in parasite cleavage release highly free radical species binds to membrane protein causes lipid peroxidation, damage endoplasmic reticulum, inhibit protein synthesis and causes lysis of the parasite.
Adverse effects: • nausea, vomiting, itching, abdominal pain, and drug fever. • Abnormal bleeding, first degree AV block, transient reticulopenia and leucopenia. • Drug interactions. Uses: • Chloroquine resistant malaria • Severe and complicated malaria
ARTIMISININ COMBINATION THERAPY ( ACT) • Artesunate-mefloquine • Artesunate -sulfadoxine-pyrimethamine • Artesunate -amodiaquine • Artesunate -chloroquine • Artemether-lumefantrine • Dihydroartemisinin-piperaquine
THE MAIN CAUSE OF THE RESURGENCE IS DRUG RESISTANCE. • Rising resistance to antimalarialdrugs • Universal Chloroquine resistance to Plasmodium falciparum • Development of resistance not only compromises the efficacy of existing antimalarial drugs but also threatens to pre-maturely terminate the useful therapeutic life of new antimalarialdrugs • Lack of effective, affordable and appropriate treatment options
CHALLENGES IN DEVELOPMENT OF NEW TREATMENT FOR MALARIA • Between 1975 and 1999, only four of the almost 1,400 new drugs developed worldwide were antimalarial, and all were at least in part the products of publicly funded research • Significant R & D effort and funding required to develop new treatments • Distribution of the treatment is difficult due to the remoteness of the areas in which the disease is most prevalent and poor health systems in malaria endemic countries
RECENT ADVANCES Malaria Drug Through Genetic Engineering • Artemisinin is the most effective treatment for malaria and the best drug for treating resistant forms • Artemisinin is made from the sweet wormwood plant found in China and Vietnam. But supplies of the plant are limited. And it takes a lot of plant material to get enough of the drug to treat one patient • Placed genes from the wormwood plant into a yeast organism and got it to produce large amounts of artemisinic acid. This acid can be made into the drug artemisinin in just a few chemical steps.
GENETICALLY MODIFIED MOSQUITO • Mosquitoes genetically engineered for malaria resistance can outcompete their wild counterparts • By producing a peptide called SM1 that blocks Plasmodium from invading the mosquito's gut, thus interrupting the parasite's development. Since it is not a naturally occurring peptide, SM1 doesn't activate the mosquito's immune system
REVERSING ANTIMALARIAL RESISTANCE • A malaria parasite gene called “pfcrt”, already confirmed as the culprit behind resistance to the drug chloroquine in the malaria species Plasmodium falciparum, may be responsible for resistance to several other antimalarial drugs • In chloroquine-resistant malaria, mutations in “pfcrt” may encourage chloroquine to "leak" out of the vacuole before it has a chance to stop the heme detoxification process • By modifyng this gene resistance to chloroquine can be reversed
VACCINES FOR MALARIA • Immunization with irradiated sporozoite will confer protection against infection • Antigens can be used for immunization in order to create antibody against the sporozoite.
CASE STUDY • One Traveler's Ordeal with Severe Malaria • Mr. VerWys suffered from malaria at Haiti • Neglected Anti malarial • Illness in Lake Charles • Diagnosis • Treatment • Malaria Visits a Child in Africa • RamadhaniShidaMashaka* was only 8 months old when he got seriously ill • Home treatment • Seeking treatment outside the home • A happy ending
CLINICAL TRIAL OF ANTI MALARIAL DRUG • Phase 1 Studies of AQ-13, a Candidate AminoquinolineAntimalarial, in Comparison With Chloroquine. • Efficacy, Safety and Pharmacokinetic of Artequin TM P. Falciparum Malaria. • Effectiveness of Artemisinin Combination Regimens in Falciparum Malaria (ACT).
Phase 1 Studies of AQ-13, a Candidate AminoquinolineAntimalarial, in Comparison With Chloroquine. • Sponsor: Tulane University Health Sciences Center. • Collaborator: National Institutes of Health (NIH). • Phase 1. • Study Type: Interventional. • Ages Eligible for Study. • Genders Eligible for Study. • Inclusion Criteria: Healthy adult volunteers. • Exclusion Criteria: Chronic medications with the exception of oral contraceptives, • Pregnancy, • Breast-feeding.
Efficacy, Safety and Pharmacokinetic of Artequin TM P. Falciparum Malaria. • Sponsor: Albert Schweitzer Hospital. • Collaborator: Mepha Ltd. • Phase II. • Study Type: Interventional. • Genders Eligible for Study. • Accepts Healthy Volunteers. • Inclusion Criteria. • Exclusion Criteria.
Effectiveness of Artemisinin Combination Regimens in Falciparum Malaria (ACT). • Sponsor: Medecins Sans Frontieres. • Collaborators: Mahidol UniversityUniversity of Oxford Disease Control, Department of Health, Myanmar. • Phase IV. • Study Type: Interventional. • Ages Eligible for Study: • Genders Eligible for Study: • Inclusion criteria. • Exclusion criteria.
Key Figures WHAT HAS TO BE DONE: • More than 700 million insecticide-treated bednets – half of those in Africa • More than 200 million of doses of effective treatment • Indoor spraying for around 200 million homes annually • Approximately 1.5 billion diagnostic tests annually
WHAT IT WILL COST • In 2010, $6.2 billion will be needed • From 2011 to 2020, roughly $5 billion per year will be need to sustain the gains of control measures • In addition, about $1 billion per year will be needed for research and development of new prevention and treatment tools
REFRENCES • www.malaria.org • World Health Organization – Article http://www.who.int/en/ • "Engineering a mevalonate pathway in Escherichia coli for production of terpenoids," by Vincent J. J. Martin, Douglas J. Pitera, Sydnor T. Withers, Jack D. Newman, and Jay D. Keasling, appeared in Nature Biotechnology, 1 July 2003. • ANTIIMALARIALS By- K D Tripathi, Essentials of medical pharmacology, 5th edition Jaypee publications. • www.anopheles.com
TIME HAS COME TO COUNT MALARIA OUT World Malaria day (25 April)- A Day to Act Blue Ribbon Campaign Launched by Malaria Foundation International
Do NOT be fooled into thinking white blood cells are Plasmodium parasites! White blood cells are larger in size than the red blood cells, and have a large, darkly staining, bi-lobed nucleus.