09/05/2014 01:44 EDT | Updated 11/05/2014 05:59 EST

Safety data expected in Nov., Ebola vaccines may be used before end of 2014

TORONTO - Experimental Ebola vaccines may be ready to be used before the end of 2014, the World Health Organization revealed Friday.

The global health agency said data from the first safety studies in humans of two experimental vaccines should be available by November, opening the door to their use initially in health-care workers tending the sick.

The word came after a two-day meeting in which nearly 200 scientists, ethicists, public health experts and representatives of drug regulatory bodies looked at the experimental drugs and vaccines in development and made recommendations on how and in whom they should be used in this outbreak, the largest on record.

The absence of treatment options has fed the panic associated with Ebola outbreaks, said Dr. Marie-Paule Kieny, the WHO's point person for the effort to push these products out of laboratories and into the field.

"We have to change the sense that there is no hope in this situation to a realistic hope," Kieny, the WHO's assistant director general for health systems and innovation, said at a news conference in Geneva.

To date the months-long outbreak has claimed an estimated 1,850 lives, and infected nearly 3,700 people in Guinea, Sierra Leone, Liberia, Nigeria and Senegal.

The meeting determined the first priority — which reflects the limits of the supplies of the experimental drugs and vaccines — is to try treating Ebola patients with the blood of Ebola survivors. While evidence on the effectiveness of this approach in Ebola is limited, so-called convalescent sera has been shown to work in some other diseases and Kieny said it was a consensus of the meeting that the approach has a good chance of being effective.

The idea behind the approach is that the blood of survivors contains antibodies that should help fight the onslaught of the disease. She said work is already underway to help affected countries roll out such programs safely, noting one silver lining of the dark cloud of this outbreak is that the huge numbers of cases are generating a growing pool of survivors from whom to seek blood donations.

Such an approach needs to be done with care, said Michael Osterholm, director of the Centre for Infectious Diseases Research and Policy at the University of Minnesota. Whole blood or blood products such as sera would need to be screened for a range of bloodborne diseases, including HIV, malaria and others.

On the issue of vaccines, this week in the United States researchers began to enrol healthy volunteers in a Phase 1 clinical trial designed to show if the vaccine in question — made by scientists at the U.S. National Institutes of Health and licensed to pharma giant GSK — is safe to use in people.

The same type of study will start soon on a second vaccine, developed at Canada's National Microbiology Laboratory in Winnipeg. The company which licensed that vaccine, NewLink Genetics, announced Thursday it had received approval from the U.S. Food and Drug Administration to start safety testing of the vaccine. Initial work will be in the United States, but follow up trials will be done in Europe and Africa.

Assuming the trials show the products are safe to use, Kieny said the Canadian-made one will likely be the first used. The Canadian government has given the WHO between 800 and 1,000 doses of the vaccine. She said the focus will be on using it in health-care works initially and noted there could be more of this vaccine available in a month or two.

And there may be as many as 10,000 doses of the GSK vaccine available by the end of the year, Kieny said.

The vaccines and the experimental drugs — such as the antibody cocktail ZMapp or TKM-Ebola, a drug being developed by Tekmira Pharmaceuticals of Burnaby, B.C. — will be used as they become available, Kieny said. But data will be collected to try to determine if the therapies are working — or if use should be discontinued.