Intermediate Trial Shows Ebola Vaccines Safe

Scanning electron micrograph of Ebola virus (National Institute of Allergy and Infectious Diseases)

27 March 2015. An intermediate-stage clinical trial in Liberia testing two new vaccines to prevent Ebola infections, shows the vaccines appear to be safe, allowing for larger-scale assessments. Initial results of the trial were reported yesterday by National Institute of Allergy and Infectious Diseases (NIAID), part of National Institutes of Health.

The 2014-15 Ebola virus disease outbreak is one of the largest ever recorded and affects mainly three countries in Africa: Guinea, Liberia, and Sierra Leone. The disease is caused by a virus spread through direct contact, often through broken skin or mucous membranes, with a sick person’s blood or bodily fluids, contaminated objects such as needles, and infected animals. The latest case counts reported by WHO and CDC show nearly 25,000 confirmed or suspected cases, and more than 10,000 deaths. Liberia recorded some 9,600 total cases and 4,300 deaths

The clinical trial with more than 600 volunteers in Liberia is testing two experimental vaccines:

– cAd3-EBOZ, developed by NIAID and GlaxoSmithKline

– VSV-ZEBOV, made by Public Health Agency of Canada and licensed to NewLink Genetics Corporation and Merck

Participants are randomly assigned to receive either an injection of a test vaccine or a saline solution placebo. Blood tests are taken immediately after, as well as 1 week and 1 month later, with follow-up blood tests 6 and 12 months following the injection. Participants will also be contacted monthly with inquiries about their health for up to 12 months.

The intermediate-stage trial, begun in early February, aims to enroll about 1,500 participants, with the primary goals to test the vaccines’ safety — evidenced by adverse reactions — and their ability to generate an immune response. NIH says the initial safety results, confirmed by an independent review board, will make it possible to complete enrollment at a hospital in Monrovia, Liberia’s capital, with completion scheduled for the end of April. With the added participants, the team is aiming to increase enrollment of women, who make up only 16 percent of the first participants.

The results also enable the research team to plan a larger late-stage trial of the vaccines with 27,000 participants testing their effectiveness in protecting against Ebola infections. Since only one new Ebola case is reported in Liberia since mid-February, however, the researchers are seeking to expand the study outside Liberia to sites in other West African countries.

Read more:

• Paper Strip Test Developed for Ebola, Other Diseases
• Biotech Licenses Cell Research for Ebola Treatments
• Project Aims to Boost Ebola Drug Production
• Ebola-Marburg Vaccine Development, Testing Contract Awarded
• U.S., Canada Authorities OK Biotech Ebola Treatments

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