Human trial of 4th Ebola vaccine launches in Australia

Hand with syringe
Hand with syringe

Steven Depolo / Flickr cc

Novavax yesterday announced the launch of the first human trial of its recombinant Ebola vaccine, which will make it the fourth candidate vaccine to be tested in phase 1 trials.

Also, the number of cases and deaths in the region continued to creep upward, as Doctors without Borders (MSF) outlined response gaps and its latest activities in the region.

Trial involves 230 adults

Novavax's product is a glycoprotein recombinant nanoparticle vaccine adjuvanted with Matrix M (Ebola GP) to boost immune response. Conducted in Australia, the study will test the safety and immunogenicity of the vaccine, with and without the adjuvant, in 230 healthy adults ages 18 to 50. Subjects will be given two intramuscular injections 3 weeks apart.

Novavax said in a statement that it expedited the vaccine's development, starting in September when outbreak virus sequence data were published. It said that two injections of Ebola GP provided nonhuman primates with 100% protection against lethal Ebola challenge. It added that antibody levels after both one and two vaccine doses in the animals were well above those reported in other nonhuman primate models and in recent phase 1 clinical trials.

Stanley Erck, Novavax's president and chief executive officer, said in the statement that, like its other recombinant vaccine candidates, Ebola GP could be rapidly scaled up to produce millions of doses.

Three other Ebola vaccines are in clinical trials. Phase 2 and 3 studies of the two vaccines that are furthest along in trials got under way in Liberia at the end of January. They include two vector virus vaccines, ChAd3, developed by the National Institutes of Health (NIH) and GlaxoSmithKline (GSK), and VSV-EBOV, developed by the Canadian government and licensed by NewLink Genetics and Merck.

A phase 1 trial of a prime-boost Ebola vaccine regimen from Johnson & Johnson launched in early January in the United Kingdom.

Outbreak developments

In outbreak region developments, the World Health Organization (WHO) said today that the number of confirmed, probable, and suspected Ebola cases has risen to 22,999, with the number of fatal cases now at 9,253. The totals include 96 new cases and 59 new deaths compared with yesterday's update.

Today's report includes data as of Feb 10 for Guinea and Sierra Leone and Feb 9 for Liberia.

Meanwhile, MSF yesterday weighed in on recent Ebola outbreak trends, raising concerns about still-weak surveillance and little information sharing among the three hardest-hit countries regarding contact tracing. "Since a single case is enough to reignite an outbreak, the level of vigilance should remain high in order not to jeopardize the progress made in stemming the epidemic," it said.

In its epidemiologic update earlier this week, the WHO pointed out an ongoing hot spot at the Guinea–Sierra Leone border and said remote cases in outlying areas of those two countries posed border threats to Ivory Coast and Senegal.

MSF said the Ebola case-patients treated in its Donka treatment center in Guinea's capital, Conakry, have risen, and that acceptance levels of outbreak response efforts among the people remains low, despite the group's outreach and sensitization activities in the city. It added that a rapid response team has been sent to Faranah to set up a transit center to handle new cases.

In Sierra Leone, the number of new admissions to MSF treatment centers is still low, with its district outreach activities a priority, the group said. A new treatment center in Kissy, a hot spot on the outskirts of Freetown, has admitted 61 patients since early January, including 9 pregnant women who have received treatment at a special maternity ward for Ebola patients that opened at the end of the month.

UNMEER probes resistance, plans Guinea surge

In response to reports of community resistance incidents in Guinea's Forecariah district, the head of the United Nations Mission for Ebola Emergency Response (UNMEER), Ismail Ould Cheikh Ahmed, visited the area yesterday to meet with community leaders and responders, according to today's UNMEER update.

Ahmed observed that although community resistance remains high from mistrust and misinformation about the disease, the high number of cases might result from a segment of the population that accepts the disease and is providing reports about sick patients. Officials also said response capacity in the area is still limited, with, for example, no lab on site and only six ambulances for the whole district.

Elsewhere in Guinea, officials are battling persistent rumors in Conakry that have disrupted school activities, UNMEER said. Rumors are spreading in the capital and other areas that Guinea Red Cross teams and others are spraying and disinfecting schools, fueling fears of contamination.

National health officials have reiterated that public areas are not to be sprayed and that spraying only applies to homes of Ebola patients.

UNMEER said it is fast-tracking a surge response to Guinea and is working with national authorities and other partners to speed those efforts.

See also:

Feb 12 Novavax press release

Feb 13 WHO update

Feb 12 MSF update

Feb 13 UNMEER update

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