Collaborative Group for Studies with Yellow Fever Vaccine Randomized, double-blind, multicenter study of the immunogenicity and reactogenicity of 17DD and WHO 17D-213/77 yellow fever vaccines in children: implications for the Brazilian National Immunizat
Collaborative Group for Studies with Yellow Fever; Camacho LAB Immunogenicity of 17DD and WHO 17D -213/77 Yellow Fever Vaccines in Children less than 2 years old: a randomized, double-blind study. In: 5th World Congress of the World Society fo Pediatric
Fox JP & Cabral AS The duration of immunity following vaccination with the 17D strains of yellow fever vírus. American Journal of Hygiene, 1943; 37:93-120.
Monath TP, Cetron MS & Teuwen DE Yellow fever vaccine. In Plotkin SA, Orenstein WA & Offit P. Organizadores. Vaccine. Philadelphia. Saunders Elsevier 2008. p. 959-1056.
Niedrig M, Lademann M, Emmerich P, Lafrenz M Assessment of IgG antibodies against yellow fever virus after vaccination with 17D by different assays: neutralization test, haemagglutination inhibition test, immunofluorescence assay and ELISA. Trop Med Int
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.
