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Medicine

Ebola Vaccine Trials Forcing Tough Choices 178

An anonymous reader writes: Medical researchers hope an experimental vaccine for Ebola can help protect against infection and slow the spread of the disease. Efficacy trials for the vaccine begin in a few months, and it's forcing some difficult decisions for health care officials. The first test will involve front line health care workers, who, as a group, are at the gravest risk of infection. But every trial needs a control group, and scientists are bitterly divided over whether the vaccine should be withheld from a portion of those putting their lives on the line to protect the rest of us. Development of the vaccine has been vastly accelerated already, due to the virus's spread and its mortality rate.

"The leading alternative is a design known as step-wedge, which essentially uses time to create a control group. In this design, researchers take advantage of the inescapable reality that large-scale trials can't give everyone the vaccine on the exact same date; they compare the rates of infection in people already vaccinated with those who have yet to receive the shots. Barney Graham, a virologist ... says "people are more comfortable" with the step-wedge design, because everyone in such a study would get the Ebola vaccine. But statistically speaking, this design makes it more difficult to determine the vaccine's worth, and it takes longer." NY Mag has a related story summarizing the treatments currently being used to fight Ebola.
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Ebola Vaccine Trials Forcing Tough Choices

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  • The difficulty in determining the effectiveness of the vaccine when you give it to everyone is dependant on how effective it is. If it reduces the chances of exposure resulting in infection by 10%, then yes, it will be tough to show that it's not useless. However, if it reduces the chances by 90%, it will be quite obvious.

    • A complicating factor is that, for most vaccination systems, the person will always in future test positive for antibodies to the virus. So, if you vaccinate someone, and some weeks/ months/ years/ decades later they report symptoms not incompatible with Ebola, then you have no way of finding out if they have Ebola, other than waiting for the disease to progress.

      Same for whatever other disease you're vaccinating against. We had this debate ad nauseam in 2001, during the FMD outbreak [wikipedia.org]. That litle point of vi

  • by Anonymous Coward on Wednesday October 08, 2014 @10:12AM (#48092031)

    Experts: Ebola Vaccine At Least 50 White People Away [theonion.com]

    "Development of the vaccine has been vastly accelerated already, due to the virus's spread and its mortality rate." Ebola isn't new. What's new is that there's now a very real chance of the infection spreading to countries where white people live. Hence the "vastly accelerated" development.

  • by gurps_npc ( 621217 ) on Wednesday October 08, 2014 @10:18AM (#48092117) Homepage
    It shouldn't be called a vaccine until it has been proven.

    Until them, we should call it something along the lines of "hopefully dead ebola virus that we think might make you immune to live ebola".

    If we call it that, then no one will complain about not getting it.

    • I don't think that this may fool the health workers, many of whom may remember the polio vaccine as "dead poliovirus that is proved to make you immune to live polio".
      Among those who are not in the health industry, "hopefully dead Ebola virus that we think might make you immune to live Ebola" is almost indistinguishable from "we think that dead Ebola virus might hopefully make you immune to live Ebola," which will be enough to make people feel deceived if they believe to have had the real shot, while havin
    • There are other ways of making a vaccine than attenuating or killing viruses.
  • by Charliemopps ( 1157495 ) on Wednesday October 08, 2014 @10:24AM (#48092233)

    Your study is doomed already. Ask the researchers that tested AIDs drugs in the 80s. People will share pills in an attempt to be sure they got the right thing. They'll buy them on the black market. They'll join multiple studies and take herbal remedies. When death is on the line people will do what they need to do to survive, your study be damned. So just give the drug to them all and save your study work for when there isn't an epidemic going on.

    • When death is on the line people will do what they need to do to survive, your study be damned.

      They'll do what they THINK will help even if there is no evidence to back that up. Just because desperate people are being (understandably) irrational doesn't mean the rest of us should join them. We do things the way we do them because it works and because the alternatives result in much worse problems [wikipedia.org].

      So just give the drug to them all and save your study work for when there isn't an epidemic going on.

      There is always an epidemic going on somewhere. The value of these studies is that it saves many at the expense of a few. That is the cold hard fact of medicine. Some people are going to die/suffer so

      • Re:Stopping (Score:4, Interesting)

        by Charliemopps ( 1157495 ) on Wednesday October 08, 2014 @11:52AM (#48093425)

        The point is... while this epidemic is going on, it will be very hard to control the study. Most Ebola outbreaks affect less than a few hundred people. There are enough people in Africa infected now that if you limit access to this Vaccine a whole cottage industry will likely spring up around it. Just like it did over AZT in the 80s. Do YOU want to be the healthcare worker guarding the stash of drugs that's the only hope for survival to the teaming throngs surrounding your clinic?

        Give it to everyone, hope for the best, when the worst is over start your study.

    • by gweihir ( 88907 )

      That is why you make sure this stuff is not available generally, and why you inject it.

  • by XxtraLarGe ( 551297 ) on Wednesday October 08, 2014 @10:25AM (#48092247) Journal
    According to the alert on CNN [cnn.com], he has just died from Ebola.
    • Jessie Jackson said Duncan was given poor hospital care and sent home even though he had ebola.

      Records show Duncan denied any contact with Ebola, any vomiting, any symptoms indicative of ebola, and was diagnosed with a low-grade viral infection and sent home.

      "I don't have ebola, I haven't been near ebola. Probably the flu." "Yeah you have flu symptoms. Here, take this and go home."

      That's different than "I carried a dying teenager into her home in her final days." "Oh SHIT! And you're ill now?!"

      • It's well known that he told the hospital staff that he had recently traveled from Liberia, hospital staff didn't act appropriately with this information.

        To be fair, it's also well known that he denied having contact with anyone ill before he boarded his flight to the US.

      • WTH are you rambling on about. You are making no sense. Pick a topic and stick with it. If your going to accuse someone of something though bring some sources would ya?
        • Sources [independent.co.uk]

          He went on to claim that Duncan had been sent home from the hospital, despite showing symptoms of the disease, "because he didn't have insurance".

          Source [npr.org]

          Officials at Texas Health Presbyterian Hospital now say Thomas Eric Duncan wasn't honest with them either. When asked if he had been around anyone who had been ill, Duncan told them he had not.

  • by nbritton ( 823086 ) on Wednesday October 08, 2014 @10:31AM (#48092309)

    The only objective is to keep them from dying, and we already know the death rate of ebola through empirical observation, so we don't need a control group.

    • Of course, if the experimental vaccine is effective, then we should be keeping people from dying and we don't need a control group. But this is an unwarranted assumption: we don't know yet if the exerimental vaccine is effective -- this is what we are trying to determine, and we won't have the answer until after the experiment.

      You say "we already know the death rate of ebola through empirical observation", but the death rate depends on many variables. For example, health-care workers probably have better

      • we don't know yet if the experimental vaccine is effective

        Effective?
        We don't even know yet if it's safe for a large population.

        • Safe and effective are both important questions. Which is why you test both questions at the same time, along with other questions (dose, administration route, adjuvants). And of course, you want to get all the answers to these questions as soon as possible, and to kill as few people as possible.
    • The objective is to keep them from getting infected. We know the mortality rate of the infected; we don't know the transmission rate in the given situation.
    • The only objective is to keep them from dying, and we already know the death rate of ebola through empirical observation, so we don't need a control group.

      I disagree strongly with your framing of this issue. The objective is (or should be) to keep the LARGEST POSSIBLE number of people from dying. This means that we have to weigh the needs of the patients who are sick right now against the needs of future patients who will become infected. The demonstrated best way to learn if a treatment is effective, safe and to learn why is through controlled studies. Often this means we sacrifice some so that more may live in the future. While i'm not suggesting we do

      • Well said. You also want to know if your vaccine causes a recipient to contract rapid onset brain cancer, or some other side effect that might be just as bad as the thing that you are trying to prevent/cure in the first place before you administer it to everyone. The Hippocratic oath contains a line about 'Do no harm'.
    • Controls save lives, because they allow you to work with less data and reach a conclusion more quickly. Note that even controlled experiments are never conclusive, but without controls you need much, much more data to make a compelling case for efficacy.

    • The only objective is to keep them from dying, and we already know the death rate of ebola through empirical observation, so we don't need a control group.

      What's the death rate through empirical observation?

    • by gweihir ( 88907 )

      Bullshit. The vaccine is not finished in the trials, a lot of optimization still needs to be done at that stage. Also, it would not be the first time that the side-effects are worse than the benefits on first trials. In order to get a handle on that, accurate effectiveness numbers and accurate estimates of side-effects are urgently needed. This process cannot be short-circuited without dire consequences.

    • Using the population (of infected people) as a control group. Say you have two potential vaccines, A and B (this could even be different dosages of the same vaccine, or different adjuvants at the same dosage, or oral vaccine versus injected). Your population mortality is 65% +/- 5% (because you do not know everyone infected, or everyone who dies) and your two candidate vaccines have mortality rates of 55% +/-15% (smaller sample size leads to higher uncertainty) and 52% +/-20% respectively.

      Back to elementa

  • by sjbe ( 173966 ) on Wednesday October 08, 2014 @11:00AM (#48092711)

    One problem with rushing a treatment to market (aside from the obvious side effects and toxicity risks) is that you sometimes end up with a treatment that works but you have no idea why it works. This has happened with some drugs in the past. We've started testing them and found that they worked really well. So we stopped the clinical trials early in order to rush the drug to market quickly for perfectly appropriate humanitarian reasons. After all if you have a drug that you know works then it's pretty cruel to withhold it from someone who would benefit. The problem is that sometimes we know a drug works before we know why or how it works.

    Part of clinical trials is figuring out if a treatment will work. The other part which is sometimes even more important is figuring out why a treatment works so that we can build off that information in the future. If you skip or stop clinical trials early you sometimes end up losing this critical information. If we don't know why something works it's pretty hard to make further progress in developing even better treatments.

    • You can always do that research in the future. Rushing a life-saving treatment to deployment is always ethical: people like to bitch about experimentation on humans and all the complications and side-effects and suffering you can cause, but this doesn't fucking apply when your human guinnea pigs are definitely going to die soon. If you can make them not die, failure is a null outcome.

      • You can always do that research in the future.

        So lives in the future are worth less than lives now? I could not disagree more. If we practiced what you suggest we would never do any studies because we would always be putting them off into the future. We use controlled studies because it is the best way to know if something works and just as importantly why it works. And yes this comes at the cost of some lives. We sacrifice some so that more may live in the future. If you can find a better way to do it then let us know and go collect your Nobel p

        • Not true. First off, we DO NOT KNOW if these treatments will work.

          Well, if you have a terminal cancer patient, and you give them no treatment, they die. If you give them a treatment and it doesn't work, they die. If the treatment has horrible side effects, you could give them a suicide pill. Or maybe the treatment just works.

          It's "unethical" to experiment on humans, and "ethical" to make ourselves feel good by simply staring at them and telling them to die so they will have the dignity of not being a human guinea pig. Which is stupid: it's unethical to withhold pot

          • by geekoid ( 135745 )

            Yes, if you create a perfect on/off death scenario, you have a point. Sadly it has no bearing what so ever in the real world.

            lets say the mortality rate is 70%

            If some dies, was it becasue of the vaccine or Ebola? If he live, is it he is jut one of the 30%, or did the vaccine work?

            • We can show that the vaccine is safe already. Besides, if more people die when on the vaccine, it's probably because of the vaccine.

              You're also using an undistributed middle fallacy: vaccines prevent contraction of the disease. Death rate is a consequence of contracting the disease. In the population, 16% may die: 80% fatality from Ebola, 20% transmission rate. A vaccine would drop the transmission rate--maybe 10% transmission rate, and 8% of the population dies.

              The question is really if the vaccin

          • by nbauman ( 624611 )

            Not true. First off, we DO NOT KNOW if these treatments will work.

            Statistics works better if you gather lots of data. For HIV, cancer, and ebola, you can gather more statistical data over time even without doing direct controlled studies. You can also compare those to animal models. You can keep cracking on the problem of why and to what degree. In other words: you can better control the experiment in a future setting, and possibly reduce risk to humans.

            Not true. That's the point -- more statistical da

            • Not true. First off, we DO NOT KNOW if these treatments will work.

              We have reason to believe the treatment will work. We also have reason to believe they're safer than death (we have reason to believe they're reasonably harmless in their own right, but that's extreme compared to the benchmark of preventing death). Thus your statement is both misleading (not entirely inaccurate) and irrelevant.

              Not true. That's the point -- more statistical data is useless if you're not collecting it in a way that will give you an answer. The only way to get an answer is with a randomized, controlled trial. Animals aren't humans.

              I see you've done no real statistics or explored any real science.

              Many mechanisms of actions for many modern drugs are explained by animal models. For example: anything that

              • by nbauman ( 624611 )

                Not true. First off, we DO NOT KNOW if these treatments will work.

                We have reason to believe the treatment will work. We also have reason to believe they're safer than death (we have reason to believe they're reasonably harmless in their own right, but that's extreme compared to the benchmark of preventing death). Thus your statement is both misleading (not entirely inaccurate) and irrelevant.

                Personally, I could accept giving drugs from Phase II trials to informed patients if the only costs were the financial costs, and the risks of adverse effects. But the real danger is that the medical community goes off in all different directions, without a strategy, and winds up with data that doesn't give them the information they need.

                It's moot, because the costs to a drug company of giving individualized premarket drugs to patients is enormous, and they don't usually have drugs available for compassiona

                • Well, gee, I read half a dozen clinical studies in the major medical journals every week and write reports on them. My boss seems to think I understand them OK. And I go to conferences where I meet the investigators and talk to them, to make sure I got it right.

                  If, like them, you have a PhD or MD and work in drug development, I'll give your opinions appropriate weight. Although I think it's commendable when a layman tries to learn more about medicine and science.

                  Short version: You've read some medical papers, which make use of statistics in experiments. I've been told I'm the only person in history to get a perfect score on the advanced placement statistics and probability exam, although I'm sure that was just the excited babble of an obsessive asian math teacher. I do have a founding grasp on statistical analysis, experimental design, and the complexities and shortcomings of studies over experiments.

                  You got me there. I can't make any sense out of that paragraph at all. Maybe I don't know what I"m talking about.

                  You went on a long tirade about how something "works half th

                  • by nbauman ( 624611 )

                    To illustrate, let's assume that Africans are terrible at running medical facilities and experience a 75% transmission rate per week: 3/4 of their healthcare providers in Ebola treatment facilities contract ebola EVERY WEEK. European facilities with similar load experience a 1% transmission rate. If your drug is 50% effective, you should immediately see a 37.5% drop in Ebola transmission in African facilities; in European facilities, you'll see a 0.5% drop.

                    Your assumptions are all wrong.

                    First, there is no ethics committee in the world that would allow western scientists to go to African clinics to perform such an experiment and not give them help in cutting their Ebola transmission. You're describing the Tuskegee syphilis study. Gowns, gloves and standard procedures would reduce transmission more than a vaccine.

                    Second, people used to do studies like you describe and they didn't produce reliable results. Drug companies used to do studies like that and still do

                    • Your arguments are silly. My way is a known, standard, valid statistical method; it's not my fault some people mis-apply them to falsify information. I can do randomized, controlled tests and produce a variety of results based on analysis. This has been done for everything from hospital survival rates to psychological studies.

                      It's been shown, for example, that you can take two hospitals with inpatient and outpatient surgeries and show that either is statistically more survivable. One hospital may sho

                    • by nbauman ( 624611 )

                      I just read this in Science, with regard to using animal studies as the basis of human treatment:

                      The littlest patient; cutting-edge mouse models fuel hope for understanding and treating cancer
                      By Jenniver Couzin-Frankel
                      Science
                      3 October 2014

                      "About 90% of cancer drugs that enter clinical trials based on upbeat mouse data fail."

                      "Dozens if not hundreds of drugs have subdued cancer in these mice. A handful have done the same for people."

                      (The article describes how a drug company had been running a clinical trial i

  • by saleenS281 ( 859657 ) on Wednesday October 08, 2014 @11:48AM (#48093371) Homepage
    The solution to this is easy, it's just ones America's puritan's can't swallow. You send over terminally ill volunteers who have a short time to live anyways. You use them as the non-vaccinated group. If they contract Ebola, you allow them an assisted death (OH THE HORROR/THINK OF BABY JESUS). Everyone wins.
    • The solution to this is easy, it's just ones America's puritan's can't swallow. You send over terminally ill volunteers who have a short time to live anyways. You use them as the non-vaccinated group. If they contract Ebola, you allow them an assisted death (OH THE HORROR/THINK OF BABY JESUS). Everyone wins.

      So your control group consists of people in poor health and weak immune systems?

      Any experimental intervension will look effective against that control.

      • Because every terminal illness causes a weakened immune system, right? If you're diagnosed with a brain tumor and given six months to live, you're likely still healthy, and your immune system is fully functioning. We aren't talking about sending full blown AIDS patients as a test group...
        • by geekoid ( 135745 )

          Any time someone says strong or weak with regard to the immune system, it's a good clue that don't actually know what they are talking about.

          And yes, people who are ill for ANY REASON have a change in their immune response.
          In your example(brain tumor), Immune cells cause the FasL to commit suicide. Sadly, the FasL proteins are created faster then the immune response can handle. If they can get the gliomas to slow down or stop the expression of the FasL protein, the immune system would take care of the tum

          • 1. I guess you should tell that to OP then, I was responding with terminology he chose. I just chose not to respond like a condescending douche. You should try it sometime.
            2. No, that's not what causes a brain tumor. I'm glad you managed to garner some buzz words in your second year biology course, but you might want to crack that book back open.

            I never claimed to "know so much about" the immune system. I guess your reading comprehension issues still persist. Now shoo troll, nobody cares.
  • Thomas Eric Duncan has died of Ebola [newslines.org]

  • it has to be done this way.
    Keep using your protocols, make the research a top priority.

  • ... I still have my stockpile of Tamiflu from the last viral epidemic.
  • Sure, it is tough, but without the control group all scientific basis for efficiency evaluation goes out the window. That leads to guesswork that routinely kills a lot more people later. That said, of course the control group should be as small as possible as it can be and still give scientifically sound results. It might also be a good idea to give the members or the control group preferential treatment when they get infected to offset the higher risk they are running. But there is no way to get around th

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