Malaria
Conditions
Interventions
Doxycycline
Sponsors
Ifakara Health Institute
Eligibility
Sex/Gender
Male
Inclusion criteria
Inclusion criteria: Male volunteers aged 18-45 years and in good health. Volunteer has adequate understanding of the procedures of the study and is able and willing (in the investigator's opinion) to comply with all study requirements. Participant is willing and able to give informed consent for participation in the trial. Participant with low malaria exposure as determined by anti-schizont ELISA Literacy in Kiswahili. Anti-schizont antibody levels below 50th centile of the most recently available population anti-schizont in Bagamoyo district
Exclusion criteria
Exclusion criteria: Any history, or evidence at screening, of clinically significant symptoms, physical signs or abnormal laboratory values suggestive of systemic conditions, such as cardiovascular, pulmonary, gastrointestinal, renal, hepatic, neurological, dermatological (e.g. psoriasis, contact dermatitis etc.), allergy, endocrine, malignant, haematological, infectious, immunodeficient, psychiatric and other disorders, which could compromise the health of the volunteer during the study or interfere with the interpretation of the study results. A heightened risk of cardiovascular disease, as determined by: an estimated ten-year risk of fatal cardiovascular disease of =5% at screening, as determined by the Systematic Coronary Risk Evaluation (SCORE); history, or evidence at screening, of clinically significant arrhythmia, prolonged QT-interval or other clinically relevant ECG abnormalities; or a positive family history of cardiac events in 1st or 2nd degree relatives 30 Kg/m2 A medical history of functional asplenia Female volunteers Confirmed parasite positive by PCR a day before challenge i.e., at C-1. Screening tests positive for Human Immunodeficiency Virus (HIV), active Hepatitis B Virus (HBV), Hepatitis C Virus (HCV) Chronic use (>30 days) of i) immunosuppressive drugs, ii) antibiotics, iii) or other immune modifying drugs within three months prior to study onset (inhaled and topical corticosteroids and oral antihistamines exempted) or expected use of such during the study period. Any recent (within 30 days) or current systemic therapy with an antibiotic or drug with potential antimalarial activity (chloroquine, doxycycline, tetracycline, piperaquine, benzodiazepine, flunarizine, fluoxetine, tetracycline, azithromycin, clindamycin, erythromycin, hydroxychloroquine, etc.) (Allowable time frame for use at the Investigator'sdiscretion). History of malignancy of any organ system (other than localized basal cell carcinoma of the
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Frequency of solicited and unsolicited adverse events. | — |
Secondary
| Measure | Time frame |
|---|---|
| Magnitude of Adverse Events both solicitated and Unsolicited. ;Rate of Mosquito infections (proportion of infected mosquitoes);Infection burden (Oocysts density in infected mosquitoes);Number of volunteers in each study arm that show prevalence of gametocytes as defined by quantitative reverse-transcriptase PCR (qRT-PCR) for CCp4 (female) and pfMGET (male) mRNA with a threshold of 5 gametocytes/mL for positivity.;Time to peak density gametocytes from the time of challenge as measured by qRT-PCR.;The area under the curve of gametocyte density versus time for both arms of the study;Gametocyte commitment after the blood infection challenge as estimated by dividing the peak gametocyte by the peak of asexual parasites;Gametocyte Sex-ratio after blood infection challenge as measured by the proportion of male gametocytes versus female gametocytes. | — |
Countries
United Republic of Tanzania
Contacts
Public ContactMoshi Shabani
Ifakara health Institute
Outcome results
None listed