[tabs tab1=”2MM Rundown” tab2= “2MM Full Report”]

[tab]

Image: PD

1. Efficacy of the RTS,S/AS01E vaccine wanes over four years.

2. The decline in efficacy is greater in areas of higher malaria exposure.

The RTS,S/AS01E is currently the most developed malaria vaccine, with its phase 3 trial slated to end in December 2014. Results continue to show that the vaccine provides a real protective effect, though the effect size is modest. At this point, it seems likely that the vaccine will augment rather than replace existing prevention and treatment methods.

This study and others like it provide data upon which evidence-based guidelines for the application of this vaccine can be based. In particular, the finding that vaccine efficacy declines over four years, especially in areas with high rates of malaria, has important implications. In the future, the authors’ method of calculating the malaria exposure index may become part of the criteria used to determine where the vaccine could be usefully deployed.

Click to read the study, published today in NEJM



[/tab]

[tab]

Image: PD

1. Efficacy of the RTS,S/AS01E vaccine wanes over four years.

2. The decline in efficacy is greater in areas of higher malaria exposure.

This [randomized] study: In a previous phase 2 study, children in sub-Saharan Africa aged 5 to 17 months, were randomly assigned to receive either an experimental malaria vaccine (RTS,S/AS01E) or a rabies vaccine. This study presents the four-year follow-up data from one of the study sites — Kilifi, Kenya.

The efficacy of the vaccine declined over the four-year period. The authors calculated that the numbers of malaria cases prevented per 100 children vaccinated in each year of follow-up were: 26, 22, 18 and -1. The incidence rate of malaria episodes in year four was the same in the vaccinated and control groups.

The efficacy of the vaccine over four years was also affected by intensity of malaria exposure. In the high exposure index group, the vaccinated and unvaccinated groups both had a similar incidence of malaria episodes by year four. In the low exposure index group, the vaccinated group continued to have a lower incidence of malaria in the fourth year.

In sum: The RTS,S/AS01E is currently the most developed malaria vaccine, with its phase 3 trial slated to end in December 2014. Results continue to show that the vaccine provides a real protective effect, though the effect size is modest. At this point, it seems likely that the vaccine will augment rather than replace existing prevention and treatment methods.

This study and others like it provide data upon which evidence-based guidelines for the application of this vaccine can be based. In particular, the finding that vaccine efficacy declines over four years, especially in areas with high rates of malaria, has important implications. In the future, the authors’ method of calculating the malaria exposure index may become part of the criteria used to determine where the vaccine could be usefully deployed.

Click to read the study, published today in NEJM

By Tomi Jun and Mitalee Patil

More from this author: Researchers improve lung cancer risk model by incorporating more risk factors, Study hints at causal link between lipoprotein(a) and calcific aortic stenosis, Peginasetide non-inferior to EPO for chronic kidney disease patients not on dialysis [PEARL Trials], Video surveillance sheds light on causes of falls in the elderly, [Researcher Comment] Whole-genome sequencing helps halt MRSA bacterial outbreak, [Physician Comment] Multiple sclerosis: Anti-cancer drug beats current first-line treatment in phase 3 trial, A molecular link between sleep deprivation and insulin resistance, A phase I trial of neural stem cells in a disease of myelination shows promising results, Diagnostic exome sequencing in persons with severe intellectual disability finds new candidate genes, HPV vaccine associated with minimal adverse effects, Four different types of breast cancer revealed based on molecular data, Acupuncture helpful for chronic pain: new meta-analysis [Arch Intern Med.]

© 2013 2minutemedicine.com. All rights reserved. No works may be reproduced without written consent from 2minutemedicine.com. Disclaimer: We present factual information directly from peer reviewed medical journals. No post should be construed as medical advice and is not intended as such by the authors or by 2minutemedicine.com. PLEASE SEE A HEALTHCARE PROVIDER IN YOUR AREA IF YOU SEEK MEDICAL ADVICE OF ANY SORT. Content is produced in accordance with fair use copyrights solely and strictly for the purpose of teaching, news and criticism. No benefit, monetary or otherwise, is realized by any participants or the owner of this domain.

[/tab]

[/tabs]