Ebola Outbreak In DR Congo: Where Are The Vaccines In Development?

Following reports of another Ebola outbreak in Africa, Scrip explores the pipeline of clinical-stage vaccines and how the companies developing immunizations are approaching the most recent cases of the viral hemorrhagic disease.

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The vaccines being advanced to tackle a new Ebola outbreak in Africa

Another outbreak of Ebola, this time in the Democratic Republic of the Congo (DR Congo), could spur pharma into action once more after a quiet period since the 2014/2015 epidemic in West Africa.

The government of DR Congo declared a new outbreak of Ebola virus disease in Bikoro, Equateur Province, in early May. It is the region’s ninth outbreak of Ebola since the discovery of the virus in the country in 1976. As of May 13, 39 Ebola cases had been reported, including two confirmed cases, 20 probable cases, and 19 deaths.

Ebola is endemic to DR Congo; the last Ebola outbreak in the region occurred in July 2017 in Likati Health Zone, Bas Uele Province, in the northern part of the country.

The World Health Organisation has released $2.6m from its Contingency Fund for Emergencies to kick-start rapid response to the most recent outbreak. The Wellcome Trust and UK Department for International Development (DFID) have also announced a commitment of up to £3m ($4.0m) to support efforts to contain and manage the disease. The WHO said the estimated budget for the international response was $25m for a three-month operation.

The Ebola virus causes an acute, serious illness that is often fatal if untreated  – the average Ebola case fatality rate is around 50%. The virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission. The large-scale outbreak of the disease in Guinea, Liberia and Sierra Leone, which began in 2014, left more than 11,300 dead.

Vaccine Progress

Merck & Co. Inc.’s investigational Phase II/III Ebola vaccine, V920, has been made available by the company for use in DR Congo and a vaccination program is set to start in the region. Merck told Scrip it was actively collaborating with the WHO and Médécins Sans Frontières (MSF) to support the implementation of an expanded access clinical protocol, designed to allow deployment V920 in a ring vaccination approach in response to the new outbreak.

“There are 4,300 doses of our investigational V920 vaccine prepositioned with the WHO in Geneva to support rapid deployment to the outbreak area,” Merck, known as MSD outside of the US and Canada, said. The company is also collaborating with the WHO to provide additional doses in Geneva to support the current response; it currently has a stockpile of more than 300,000 emergency use dose equivalents.

Merck is developing V920 in partnership with NewLink Genetics. The companies are expected to release top-line data for the product in the second quarter of 2018 from the Phase II/III STRIVE trial and the Phase III SAFETY study. The vaccine is experimental and not licensed, but it was tested in Guinea in 2015.

The Ebola vaccination campaign will first target health workers in DR Congo. Recent reports have noted that three nurses were among those with suspected cases of the disease, and another was one of the fatalities. The WHO told Scrip it has dispatched 4,000 vaccine doses to DR Congo, which arrived on May 16, and that it would deploy 4,000 more in the coming days. 

As well as Merck’s program, Johnson & Johnson and GlaxoSmithKline PLC also have late-stage Ebola vaccines in development.

Ebola Clinical Pipeline

Drug Name

Lead Company

Current Phase

Drug Classification

MVA-BN Filo/Ad26.ZEBOV

Johnson & Johnson

III

Vaccine

cAd3-EBO Z

GlaxoSmithKline

II/III

Vaccine

ZEBOV

Merck & Co.

II/III

Vaccine

GBV006

Globavir Biosciences

II

Non-NME

Remdesivir

Gilead Sciences

II

New Molecular Entity (NME)

ZMapp

Mapp Biopharmaceutical

I/II

Biologic

EBOV GP Vaccine

Novavax

I

Vaccine

Galidesivir

BioCryst Pharmaceuticals

I

NME

INO-4212

Inovio Pharmaceuticals

I

NME

REGN3470-3471-3479

Regeneron Pharmaceuticals

I

Biologic

Biomedtracker

GSK told Scrip that in response to the Ebola outbreak in 2014, the company progressed its candidate Ebola vaccine into Phase II trials. “However, due to the welcome drop in Ebola cases by mid-2015, the vaccine candidate did not complete Phase III efficacy testing,” a spokesperson for the company said.    

After the end of the 2014-15 Ebola outbreak, GSK did not submit its vaccine for licensure because its clinical efficacy had not been sufficiently established due to the reducing number of cases of the disease. “We have stockpiled doses of our Ebola candidate vaccine and are closely monitoring the current situation. We are also aware that the WHO is assessing the situation to determine how best to respond to arising needs,” GSK said.

The pipeline also includes earlier stage vaccine candidates and therapeutics to treat the disease. There are also more than 10 programs against Ebola in the preclinical setting.

Ebola Therapies

As well as vaccine candidates, there are a few therapeutic treatments in development for Ebola, including Mapp Biopharmaceutical Inc.’s ZMapp. The investigational biologic is composed of three humanized monoclonal antibodies manufactured in plants.

Mapp has an expanded access protocol with the FDA for ZMapp. The company told Scrip it would provide drug in DR Congo under this protocol once it had been requested, which it expects “will be once the basic infrastructure is in place to treat patients and the local government approves its use.”

The US’s Biomedical Advanced Research and Development Authority is funding development of two therapeutics for Ebola, including ZMapp, and two vaccine candidates.