Even researchers whose trial of a potential drug for Ebola made headlines last week worked hard to minimize the glare efficiency, it showed. "It is a weak signal in a non-randomized trial," Yves Levy, director of the French Institute of Health and Medical Research (INSERM) in Paris said Science on the data, which has not published INSERM. Low or not, the ratio The New York Times that favipiravir, a drug against the Japanese flu had halved mortality in a group of patients Ebola in Guinea was a piece of good news that complicates prospects for testing over other Ebola drugs.
the Guinean government has already announced that he wants to favipiravir to more people, and if the results hold for further review, they could force a change in the design of further clinical trials move on front. Meanwhile, the decline in new cases investigators revamping or even cancellation of tests at a time when manufacturers have finally enough material to test some of the most promising experimental drugs. The balance sheet of the epidemic checked last week, Guinea, Liberia and Sierra Leone-three countries counted 124 confirmed cases most affected, against 99 cases the previous week. As Bruce Aylward said the World Health Organization (WHO) at a press conference on 5 February: "The virus has told us this week, loud and clear:" I will not go the way you me expected. "Still, the figures represent a sharp drop in the height of the epidemic in September when there were more than 700 cases reported in one week in West Africa.
Last week, the Wellcome Trust, a charitable organization in the UK which funds several Ebola trials, announced that the trial of Liberian brincidofovir, antiviral developed by Chimerix Durham, North Carolina, would be canceled because the company withdrew its support. "It was quite a surprise to us and a bit of a mystery," said Peter Horby, a researcher at the University of Oxford in the United Kingdom who led the study. Chimerix said he made the decision after discussions with the US Food and Drug Administration (FDA), noting that the trial was also to have patients of difficulty recruiting. Horby said his group was planning to open a second test site in Sierra Leone, where the numbers are much higher. Luciana Borio FDA said Chimerix also refused the request of the agency to make public its correspondence with the company. Chimerix said he focused on the completion of drug trials treat other infections :. cytomegalovirus and adenovirus
Although a trial is canceled, others are about to move forward. Horby said his group hopes to begin evaluating an RNA inhibitor called TKM-Ebola soon. the drug, manufactured by Tekmira Pharmaceuticals in Burnaby, Canada, has worked in monkeys, but has been in short supply.
The test is about to begin on the zmapp antibody cocktail. Seen by many researchers as the best shot to treat Ebola due to promise monkey studies, zmapp was used in nine patients last summer before the company behind it, Mapp Biopharmaceutical of San Diego, California, announced he had no more supplies. Now the company says it has enough doses to begin a clinical trial in Liberia this week. But there may be too few patients in this country for the experimental drug to prove its value, says Clifford Lane, director of clinical research at the US National Institute of Allergy and Infectious Diseases, which launched the study in Monrovia with the Liberian Ministry of Health and welfare.
So far, Guinea and Sierra Leone, where the Ebola virus is still infecting dozens of people a week, declined invitations to join the study. Their main stumbling block is the test design. Zmapp will be the first Ebola treatment that will be tested in a randomized controlled trial. "I think that the only way to know if these drugs are safe and effective," says Lane.
The governments of Guinea and Sierra Leone as well as Doctors Without Borders, which operates centers Ebola in these countries were for ethical reasons reluctant to participate in treatment trials using a randomized design, controlled. Jeremy Farrar, director of the Wellcome Trust, also opposes the randomized controlled trial design for Ebola drugs given the high mortality rate of the disease. "given the data we have animals and individual patients, I would not be comfortable to be random," he said.
Lane notes that the trial may not need many participants: If the drug is 100% effective and Ebola kills 50% of people infected, he said, as little as 30 people will need to receive zmapp to see if it works. And even if there are not enough patients to provide a clear answer on efficiency, Lane says that scientists could still get valuable information by looking at parameters such as blood levels of Ebola virus in those treated with the drug and the control arm.
study favipiravir in Guinea illustrates the complexity to discern clear answers without robust control and difficulties in communicating. Test data are reviewed every 20 patients by an independent supervisory board. On January 26, they evaluated data from 80 patients. Because they have detected a signal of efficacy, they asked the researchers to share information with regulators in Guinea and France, said Levy. INSERM researchers do not make public their data up to February 25, at the Conference on Retroviruses and Opportunistic Infections in Seattle, Washington. "It is important to have a scientific debate about what these results really mean," said Levy, noting that the organizers of the meeting stressed the data under embargo. A researcher who had seen the data and asked not to be identified said Science favipiravir that did not help all patients treated with it at two test sites in Guinea. In a subset of trial participants who had low levels of Ebola virus in the blood, however, the mortality rate was only 15%. Among similar patients who entered centers earlier and did not receive favipiravir, mortality was 30%. Marie-Paule Kieny, Assistant Director-General of WHO, said it was difficult to make sense of the data at this stage. "You can say it means nothing or you can say that it is promising. More research is needed to know what happened."
Meanwhile, the study in Guinea continues and has enrolled more than 100 patients. "The end result can still be different," says Levy. But preliminary data have already led the Guinean authorities to increase the number of sites where favipiravir be used.
Further tests may be more difficult organize and interpret if favipiravir is widely distributed. a study testing the use of convalescent serum began in Guinea this week. "if there is a decision now to use favipiravir everywhere, what happens with this trial ? »Request Kieny. The zmapp trial may also be affected. This trial is designed to compare zmapp with the standard of care. "If the level of care changes, as is the control used in the trial," said Lane. But he did not see any results, he said. "The only information that I have seen in this study are what was in the New York Times "
* Ebola files. Since the Ebola current epidemic, unprecedented in terms of number of people killed and the rapid geographic spread, science and science Translational Medicine made a collection of research articles and news on the viral disease available for researchers and the general public
* Correction February 13 11:05 :. This story refers to evil zmapp a trial, an Ebola antibody cocktail, as a placebo-controlled trial. as reports of history, zmapp will be tested in a trial which, for the first time, used a randomized control group. But the control group will receive a placebo. People in the control arm will receive the current standard of care, which comprises providing intravenous fluids, balancing electrolytes, maintaining the state of oxygen and blood pressure, and treating other infections if they occur.
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