Vaccines trial

Mehrishi JN, Szabo M, Bakacs T (2007) Some aspects of the recombinantly expressed humanised superagonist anti-CD28 mAb, TGN1412 trial catastrophe lessons to safeguard mAbs and vaccine trials. Vaccine 25 3517-3523... 

Pang, X. L., Joensuu, J., and Vesikari, T. (1999). Human calicivirus-associated sporadic gastroenteritis in Firmish children less than two years of age followed prospectively during a rotavirus vaccine trial. Pediatr. Infect. Dis. J. 18,420 26. 

There is no good animal model for infection by HIV. The virus will infect several primates, but it does not produce active disease and it is not practical to use primates for propagation of the virus. The chimpanzee has been used in vaccine trials to determine whether neutralizing antibody is produced and whether the growth of the virus can be inhibited in vivo. More productive work has been done using the immunodeficiency viruses of the species (e.g., simian immunodeficiency virus in macaques, feline immunodeficiency virus in cats) to study pathogenesis and treatment of retroviral acquired immunodeficiencies. 

In a trial, the parameters for comparison may be the mean level of cholesterol (in the case of a cholesterol-lowering drug), the amount of antibodies in the body (a vaccine trial), or the reduction in the size and severity of tumor (a cancer trial). A test statistic is normally used to compute and compare the means for the placebo and active groups. 

Source Meier P. The Salk Vaccine Trials, http //www.math.uah.edu/siegrist/ma487/salk.html [accessed Jauuary 2,2002]. 

The randomised part of the Salk Polio Vaccine trial has all the hallmarks of modern day trials randomisation, control group, blinding and it was experiences of these kinds that helped convince researchers that only under these conditions can clear, scientifically valid conclusions be drawn. 

As opposed to the development of vaccines that produce antibodies, the development of T-cell vaccines is a novel concept. These vaccines are designed to induce primarily T-cell responses that will control the viral proliferation and viral levels during the early stages of infection and will delay the disease progression. These vaccines will not prevent infection but will inhibit HIV levels and protect uninfected memory CD4+ T cells. It is expected that HIV-infected patients receiving this vaccine may remain disease-free for a prolonged period of time. A number of current HIV vaccine trials have focused on CD8+ cell-mediated products that... 

TSA-9 and TSA-18 were found to act synergistically results represent those of vaccination trials using the two antigens together. 

Lightowlers, M.W., Jensen, O., Fernandez, E., Iriarte, J.A., Woollard, D.J., Gauci, C.G., Jenkins, D.J. and Heath, D.D. (1 999) Vaccination trials in Australia and Argentina confirm the effectiveness of the EG95 hydatid vaccine in sheep. International Journal for Parasitology 29, 531-534. 

Progress towards human trials raises the thorny question of how to evaluate vaccine success in humans, because protection in experimental animals has almost invariably been measured by worm recovery. One exception was the small-scale attenuated vaccine trial in chimpanzees (Eberl et a/., 2001), where estimates of protection were based on faecal egg output and circulating antigen levels but could not be validated against worm burden for ethical reasons. More recently, these indirect estimators of worm burden have been evaluated with respect to actual recoveries in baboons exposed to the attenuated vaccine, revealing their significant overestimation of protection levels (Kariuki et al., 2004). This issue needs to be addressed before we proceed to full-scale vaccine trials for schistosomiasis mansoni but may be less crucial for schistosomiasis haematobia where egg output in the urine is easier to measure. 

Audran, R., Cachat, M Lurati, F., et al. (2005) Phase I malaria vaccine trial with a long synthetic peptide derived from the merozoite surface protein 3 antigen. Infect. Immun. 73(12), 8017-8026. 

HIV HIV Databases Los Alamos National Laboratory Contain data on HIV genetic sequences, immunological epitopes, drug resistance-associated mutations, and vaccine trials (http //www.hiv.lanl.gov/content/index)... 

Dorozynski A, Anderson A. Deaths in vaccine trials trigger French inquiry. Science 1991 252(5005) 501-2. 

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