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WHO International Clinical Trials Registry Platform

The World Health Organization (WHO) has a Web site to help researchers, doctors and patients obtain information on clinical trials. Now you can search all such registers to identify clinical trial research around the world!




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Pregnancy Timeline by SemestersDevelopmental TimelineFertilizationFirst TrimesterSecond TrimesterThird TrimesterFirst Thin Layer of Skin AppearsEnd of Embryonic PeriodEnd of Embryonic PeriodFemale Reproductive SystemBeginning Cerebral HemispheresA Four Chambered HeartFirst Detectable Brain WavesThe Appearance of SomitesBasic Brain Structure in PlaceHeartbeat can be detectedHeartbeat can be detectedFinger and toe prints appearFinger and toe prints appearFetal sexual organs visibleBrown fat surrounds lymphatic systemBone marrow starts making blood cellsBone marrow starts making blood cellsInner Ear Bones HardenSensory brain waves begin to activateSensory brain waves begin to activateFetal liver is producing blood cellsBrain convolutions beginBrain convolutions beginImmune system beginningWhite fat begins to be madeHead may position into pelvisWhite fat begins to be madePeriod of rapid brain growthFull TermHead may position into pelvisImmune system beginningLungs begin to produce surfactant
CLICK ON weeks 0 - 40 and follow along every 2 weeks of fetal development


CDC clinical trial for experimental Zika vaccine

The US Centers for Disease Control and Prevention has approved clinical trial status for another experimental Zika vaccine. The drug will be tested on a small sample of human participants, a mere five months after the World Health Organization declared Zika a public health emergency.

The vaccine, named GLS-5700, is a collaborative effort between Inovio Pharmaceuticals of Pennsylvania, USA and GeneOne Life Science of South Korea. The companies announced a phase I study with just 40 healthy subjects to evaluate the safety, tolerability, and efficacy of the drug.

“We are proud to have attained the approval to initiate the first Zika vaccine study in human volunteers,” noted Inovio CEO J. Joseph Kim in a statement. “As of May 2016, 58 countries and territories reported continuing mosquito-borne transmission of the Zika virus; the incidences of viral infection and medical conditions caused by the virus are expanding, not contracting.”

The company plans to start clinical trials in a few weeks and expects to report the results later in 2016. Should things go well, the vaccine will be promoted to phase II clinical trials. Things are moving quickly, but it could still take years before GLS-5700 can be used in the field.

During preclinical testing, this vaccine proved itself in animal models, “demonstrating the product’s potential to prevent infection from this harmful pathogen in humans.”

It’s pretty remarkable that clinical testing for a disease that only attained emergency status a few months ago has already been slated for clinical testing. Up until recently, scientists knew very little about this obscure virus that was deemed largely harmless. But we now know differently.

Zika, as a mosquito-spread flavivirus, is similar to Dengue and West Nile—disease for which vaccines are already under development. Scientists did not have to start this experimental new Zika vaccine from scratch.

WHO’s Regional Office for the Americas (PAHO) has been working closely with affected countries since May 2015. PAHO has mobilized staff and members of the Global Outbreak and Response Network (GOARN) to assist ministries of health in strengthening their abilities to detect the arrival and circulation of Zika virus through laboratory testing and rapid reporting. The aim has been to ensure accurate clinical diagnosis and treatment for patients, to track the spread of the virus and the mosquito that carries it, and to promote prevention, especially through mosquito control.

The Organization is supporting the scaling up and strengthening of surveillance systems in countries that have reported cases of Zika and of microcephaly and other neurological conditions that may be associated with the virus. Surveillance is also being heightened in countries to which the virus may spread. In the coming weeks, the Organization will convene experts to address critical gaps in scientific knowledge about the virus and its potential effects on fetuses, children and adults.

WHO will also prioritize the development of vaccines and new tools to control mosquito populations, as well as improving diagnostic tests.

Christian Lindmeier
Communications Officer, WHO

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Jun 28, 2016   Fetal Timeline   Maternal Timeline   News   News Archive   

Infant born with microcephaly is held by relative in Recife, Brazil.
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