WHO research and development on Zika
Dr Marie-Paule Kieny
Assistant Director-General, Health Systems and Innovation
The Ebola outbreak of 2014-15 highlighted the need for a master plan for research and development (R&D) to both prepare for health emergencies and to be able to mount a fast response in case of need. The World Health Organization's "R&D Blueprint" aims to accelerate the availability of medical countermeasures during epidemics and limit damage as much as possible. We have now established critical paths for coordinated action and industry interest in providing platform technologies for the development of medical products.
Our relatively poor knowledge of the Zika virus presents a series of challenges for research and development. However, building on experience from the Ebola epidemic, WHO has been able to set in motion a rapid R&D response for Zika.
We have already identified a large number of manufacturers and research institutions either involved in the development of medical tools for Zika, or interested in embarking on such research.
Embarking on vaccine and diagnostic research
Numerous groups are looking at the feasibility of initiating animal or human testing, particularly for vaccines and diagnostics.
For vaccines, the landscape is evolving swiftly, and numbers change daily. About 15 companies and research groups have been identified so far, though most have only just started work.
"WHO aims to accelerate the availability of medical countermeasures during epidemics and limit damage as much as possible."
Dr Marie-Paule Kieny, Assistant Director-General - Health Systems and Innovation
Two vaccine candidates seem to be at a more advanced stage: a DNA vaccine from the US and an inactivated product from India.
Still, the current absence of standardized animal models and reagents is a hindrance. And although the landscape is encouraging, it will be at least 18 months before vaccines could be tested in large-scale trials.
For diagnostics, 10 biotech companies have been identified so far that can provide nucleic acid or serological tests. Nucleic acid tests are based on a molecular technique used to detect a virus in the blood; serological tests measure the levels of antibodies as a result of exposure to a particular virus.
Models for independent assessment
In the affected region, ANVISA, the Brazilian regulatory authority, has assessed and authorised the use of some of the few commercially available diagnostics. Most other tests are still in development. The biggest task in the area of diagnostics remains ensuring that manufacturers measure against an adequate reference method when generating their data, so that the performance of the various Zika diagnostics can be tested through an independent assessment. This will help prevent the distribution of poor-quality or fake Zika tests that are sure to emerge as was the case with Ebola.
Laboratory-based Zika diagnostics (mostly non-commercial) are already playing an important role in helping us better understand this outbreak. However, new validated and broadly-available diagnostics are urgently needed to step up research, clinical management and surveillance. Although it is difficult to predict the time for the first commercial and independently-validated tests to be available, we are talking weeks or months, not years.
WHO will continue monitoring the development of diagnostics and vaccines, as well as therapeutics, and innovative mosquito control measures. These analyses will be published on our web site in the coming weeks.
We will then convene independent experts to gauge which of these products seem the most promising as they move to the testing phase.
Profiling innovative methods
At the same time, WHO is developing what is called "target product profiles" for these medical tools - for example, to determine the best characteristics for a vaccine to immunize women of child-bearing age.
In terms of diagnostics, we need to understand which type of product – nucleic acid, serologic, rapid test, etc. – will best serve our purposes. We should have target product profiles ready in the next weeks.
In the area of therapeutics, studies are being carried out on medicines and other therapies that could prevent infection in vulnerable groups, especially pregnant women, as is done for malaria. This seems for the moment a more viable and faster option than a curative treatment.
For mosquito control, innovative methods seem promising. Biological approaches for example, such as the controlled release of bacteria to prevent viral replication in mosquitoes; or genetic approaches, such as the release of genetically modified mosquitoes to reduce the mosquito population, are under consideration.
Accelerating R&D and ensuring quality
When potential products reach an advanced stage of testing and show promising data, we have in place the WHO Emergency Assessment and Listing procedure for the use of experimental products during an epidemic. This accelerated assessment process was established during the Ebola epidemic and aims to ensure that products meet acceptable levels of quality, safety and efficacy – even if evaluation is fast-tracked - before they are rolled out in countries.
WHO will also provide support to countries wishing to register proven products to compress the time it takes to carry out ethical and regulatory reviews, so that these tools become available rapidly.
Ebola taught the global R&D community many valuable lessons, and proved that when we work together, we can develop new medical products much faster than we thought possible.
Although we know even less about Zika than we did about Ebola, we are learning more every day and are much better prepared to advance much-needed research to blunt the threat of Zika as we did with Ebola.