Potential Dengue Vaccine Shows Promise
in Thailand
Trial Jul 31, 2012 By Robyn Correll C... French pharmaceutical company Sanofi
Pasteur announced Wednesday that its dengue vaccine candidate showed
significant success during a study conducted in Thailand. Roughly
4,000 children between the ages of 4 and 11 years old received three doses of
the vaccine, given in six-month intervals. An immune response was
observed against four serotypes of the dengue virus after three doses, and
showed minimal adverse effects following each dose.“Results of this first efficacy
trial with Sanofi Pasteur’s dengue vaccine candidate represent a key milestone
in the quest to develop a safe and efficacious human vaccine against dengue,”
said Michel De Wilde, executive vice president of research and development at Sanofi
Pasteur. While the vaccine candidate produced an immune response to fight the
four types of the dengue virus, researchers say that sufficient protection was
only offered against three. As the vaccine candidate moves onto further trials,
the company stated that it will conduct further analyses to understand the lack
of protection against the fourth subtype in the context of Thailand. The full results of the
study are currently under review by scientific experts and health officials,
and details of the study will be published and presented to the scientific
community later this year. The vaccine candidate is a
live attenuated vaccine, meaning that it uses a weakened version of the
causative agent, which is in this case the dengue virus, to stimulate an immune
response. The dengue vaccine contains four antigens to target all four
serotypes of the virus. Live attenuated vaccines are used to protect
against a variety of diseases, such as measles, polio and yellow fever. They
are considered to be the most effective type of vaccine. With only one or two
doses, they can elicit lifelong immunity. Other types of vaccines use dead
versions of a pathogen (modern flu vaccines) or subunits (pieces) of a pathogen
(HPV vaccine) to stimulate a response. But those often require a larger dose or
a booster to provide protection. Opting for the live attenuated vaccine has its
challenges. For starters, it is a live organism, and therefore has to be kept
alive. Areas without electricity or a method to keep the vaccine chilled prior
to distribution are at a disadvantage. Sanofi Pasteur
stated that the Food and Drug Administration has given a “fast-track”
designation to the company’s research of the vaccine candidate, in order to
“address an important unmet medical need for a serious disease.” Currently,
there is no cure and no effective treatment for dengue. Recent efforts have
focused on control and elimination of the Aedes aegypti mosquito, the insect
responsible for passing the virus between humans. An effective vaccine could help
protect the nearly three billion people at risk for dengue infection and save
20,000 lives each year. Researchers are
currently conducting a larger study of over 30,000 participants in 10 countries
in Latin America and Asia. The data collected
there will provide more information about how the vaccine fairs against the
four subtypes in a variety of settings.
赛诺菲巴斯德研发出登革热疫苗 发布时间：2012-8-16 来源：药品资讯网信息中心赛诺菲下属疫苗事业部赛诺菲巴斯德日前宣布，在泰国进行的世界上迄今为止首次效力试验证明，四价登革热候选疫苗对威胁近30亿人口的登革热具有免疫效力及卓越的安全性。证据显示，该疫苗对四种登革热病毒血清型均可诱发抗体反应。试验证据显示，该疫苗对在泰国流行的四种病毒血清型中的三种具有免疫保护作用。目前，在泰国特殊的流行病学背景下，相关机构正试图通过分析了解该疫苗对第四种病毒血清型不具保护作用的原因。赛诺菲巴斯德研究与开发执行副总裁Michel De Wilde博士说：“在努力开发安全有效的人用登革热疫苗的道路上，赛诺菲巴斯德登革热候选疫苗首次效力试验取得的成果是一个非常重要的里程碑”。对于全球公共卫生事业来说，这也是一个重要的开发项目，因为目前对于登革热，还没有针对性的治疗或预防手段。我们将竭尽所能，尝试通过疫苗预防登革热，为全世界生活在疫区的人们提供一种安全有效的疫苗。值得重视的是，研究结果证实了候选疫苗卓越的安全性。目前，亚洲及拉丁美洲10个国家正在对登革热疫苗进行大规模Ⅲ期临床研究，共有31000名受试者参与。研究还将在更大的人口范围以及各种流行病学背景下收集更多的重要资料，证明该疫苗对四种登革热病毒血清型的免疫效力。赛诺菲巴斯德登革热研究疫苗正处于临床研究阶段，已对美国、亚洲及拉丁美洲成人及儿童群体进行了接种评估。总的来说，受试者在接种三剂疫苗后对所有四种不同血清型登革热均产生了免疫反应，对试验疫苗的耐受性良好，而且在每次接种后表现出相似的安全性。该研究疫苗主要用于生活在亚洲和拉丁美洲疫区的儿童和
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