WHO urges use of survivors’ serum against Ebola, backs vaccine trials

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(Reuters) – The World Health Organization (WHO) said on Friday blood-derived products and serum from survivors may be used to treat Ebola virus immediately and two vaccines could be available for health workers by year-end.

Existing supplies of all experimental medicines are limited and will not be sufficient for months to come, while the outlook for vaccine supplies looks “slightly better”, the WHO said in a statement after two-day talks attended by nearly 200 experts.

But good clinical care, rigorous infection prevention and control measures, and the tracing of people who have been exposed remain crucial for ending an epidemic that has killed at least 2,097 in West Africa since March, the U.N. agency said.

“There is a real opportunity that blood-derived products can be used now. This can be very effective in terms of treating patients,” WHO assistant director-general Marie-Paule Kieny told a news conference in Geneva.

“With the negative point that we have so many patients, one positive point is there are also many people now who are convalescent, who survived and are doing well, These people can provide blood, serum to treat,” she told a news conference.

“What is available will be used in the field to treat real patients as soon as possible.”

Studies suggest that blood transfusions from Ebola survivors might prevent or treat Ebola virus infection in others, but it is not known whether antibodies in the plasma of survivors are sufficient, according to the United Nations health agency.

Two “promising” Ebola vaccines have also been identified after showing promising results in animals, and safety results from human clinical trials may be available from November, paving the way for their use, Kieny said.

The two vaccines are made by GlaxoSmithKline Plc and NewLink Genetics, according to WHO documents.

“These must be prioritised in terms of clinical development,” Kieny said.

Clinical trials of the GSK vaccine have begun in the United States, while trials for the NewLink vaccine will start by mid-September in Europe and Africa, she said.

Pending initial results on the vaccines’ safety, expected in November, they will be given to health care workers in the field as a priority, with their informed consent, she said.

“If we have good safety data, if the results are positive, they will start to be used in health care workers in order to protect and also to evaluate if it protects them,” Kieny said.

“We will have results of safety by November 2014 and after that these vaccines will start to be rolled out starting with health care workers and front line workers in the field.”

ZMAPP DRUG “ENCOURAGING”

ZMapp, made by the U.S.-based Mapp Biopharmaceutical Inc., has been given to seven people infected with Ebola, including two American aid workers and a Briton who all recovered, but it remains unproven and supplies have run out. The U.S. government pledged up to $42.3 million this week to accelerate its testing.

“For the time being there’s not enough experience to conclude whether this treatment works or not,” Kieny said of the antibody drug ZMapp. “There seem to be encouraging signs.”

“As soon as there are supplies available they will be tried.”

Dr. Larry Zeitlin, president of the California-based Mapp Biopharmaceutical, told Reuters that Washington’s support was vital to conducting early-stage safety studies of the drug as the jury is still out on both its safety and efficacy.

“The U.S. support will enable us to figure out what the appropriate dose is and scale up manufacturing. With a drug you have not only to make it, but make it consistently to the same quality. The award given us is for 18 months. We will probably be in human trials beginning in 2015,” Zeitlin said in an interview on Friday on the sidelines of the WHO meeting.

“We don’t have data indicating whether ZMapp is safe in humans, we don’t have data that it works in humans. That is the whole point of performing clinical trials,” he said.

WHO urges drug companies, regulators to speed Ebola work

The World Health Organisation (WHO) called on Thursday for pharmaceutical companies and regulatory agencies to work together to accelerate development of safe and efficient drugs and vaccines against Ebola.

Ten experimental treatments – eight drugs and “two promising candidate vaccines” – have shown potential against the virus but remain under investigation, the WHO said in a document distributed at the start of a two-day meeting in Geneva.

They include the antibody drug ZMapp made by U.S.-based Mapp Biopharmaceutical Inc., which has been given to several Ebola patients for “compassionate care” but whose clinical effectiveness is “still uncertain”, it said. “Efforts to scale up production (of ZMapp) may yield increased supplies of potentially a few hundred doses by the end of 2014.”

Evidence of the effectiveness of the medicines and vaccines is “suggestive but not based on solid scientific data from clinical trials,” the WHO said. Existing supplies of all experimental medicines are extremely limited or exhausted.

The virulent disease, which has killed at least 1,900 people in West Africa since March, could affect 20,000 by the time it is contained in the next six to nine months, the WHO has said.

“Accelerating the development of experimental/not approved Ebola Virus Disease therapies and vaccines require a concerted effort by product developers and regulatory agencies, in cooperation with the WHO,” the WHO paper said.

Decisions on which products go into accelerated development should be transparent and involve the West African countries affected by the epidemic, it said.

“While there is an urgent need for product to be used on a compassionate basis, the ultimate goal should be product approval so that countries affected by Ebola Virus Disease have products which have been demonstrated safe and effective at their disposal.”

“THE HOPE OF WHAT WE ARE GOING TO HAVE”

Marie-Paule Kieny, WHO assistant director-general who is chairing the closed-door talks attended by more than 150 experts, said the meeting would focus on developing the most promising drugs in the quickest possible time.

“Developed in terms of getting them to registration and developed in terms of putting them in the treatment center as much as possible in order to make a difference in the lives of people,” she said.

The WHO paper said that while supplies of experimental drugs are limited “the prospects of having augmented supplies of vaccines quickly look slightly better”.

Human safety trials are due to begin this week on a vaccine from GlaxoSmithKline Plc and later this year on one from NewLink Genetics Corp. Johnson & Johnson said on Thursday that clinical trials of its vaccine would commence in early 2015, accelerated from late 2015 or early 2016.

NewLink Genetics Corp NLNK.O said the U.S. Food and Drug Administration (FDA) allowed the Iowa-based company to start testing an experimental Ebola vaccine in humans.

NewLink founder Charles Link told Reuters on the sidelines of the Geneva talks on Thursday: “The clinical trials do take some time. Everybody is trying as hard and furiously as possible to move those trials forward as rapidly as possible with the regulations, scientific and ethical constraints.

A treatment by Tekmira Pharmaceuticals of Vancouver, Canada, that targets two viral genes to stop the virus from replicating, may be available in limited supplies, the WHO said. “There is potential for the production of 900 courses by early 2015.”