We interrupt our usual program for a pandemic update: Pfizer claims its coronavirus vaccine is 90% effective

If this is true, it’s excellent news. Click on screenshot to read the CNN report (see also the Washington Post report here):

An excerpt:

Drugmaker Pfizer said Monday an early look at data from its coronavirus vaccine shows it is more than 90% effective — a much better than expected efficacy if the trend continues.

The so-called interim analysis looked at the first 94 confirmed cases of Covid-19 among the more than 43,000 volunteers who got either two doses of the vaccine or a placebo. It found that fewer than 10% of infections were in participants who had been given the vaccine. More than 90% of the cases were in people who had been given a placebo.

Pfizer said that the vaccine provided protection seven days after the second dose and 28 days after the initial dose of the vaccine. The final goal of the trial is to reach 164 confirmed cases of coronavirus infection.

In a news release, the pharmaceutical giant said it plans to seek emergency use authorization from the US Food and Drug Administration soon after volunteers have been monitored for two months after getting their second dose of vaccine, as requested by the FDA.

I believe that 50% effectiveness is the threshold for FDA approval. And, of course, this is early days; but you can’t deny that this looks good so far.


  1. Filippo
    Posted November 9, 2020 at 7:11 am | Permalink


  2. Posted November 9, 2020 at 7:21 am | Permalink

    European stock markets have jumped 5% on this news (e.g. owner of British Airways up 40%, etc).

    I guess the Biden victory (and perhaps the Senate *not* going Democrat) are also contributing to stock-market buoyancy.

  3. jezgrove
    Posted November 9, 2020 at 7:27 am | Permalink

    Yes, it sounds like a step forward though they will only be able to produce 50m shots by the end of this year so there will be some wrangling over how they get distributed. https://www.bbc.co.uk/news/health-54873105

    • George
      Posted November 9, 2020 at 7:34 am | Permalink

      You need two shots – so only enough for 25mm people. Still, great news.

      • jezgrove
        Posted November 9, 2020 at 12:21 pm | Permalink

        Thanks George, yes I should have spelled that out more clearly.

  4. eric
    Posted November 9, 2020 at 7:28 am | Permalink

    Great news. So with the two month monitoring, we’re looking at best-case scenario, potentially a vaccine on the market by mid-Jan? That would certainly be nothing to complain about.

  5. TireGuy
    Posted November 9, 2020 at 7:32 am | Permalink

    I’ll bet there will be accusations of Pfizer withholding this news until after the election.

    • eric
      Posted November 9, 2020 at 7:48 am | Permalink

      Look down. 🙂

      Because there’s nothing a pharmaceutical company loves more than a President determined to expand medicare, given them more bargaining power to lower drug prices.

  6. Posted November 9, 2020 at 7:33 am | Permalink

    This is evidence of the Big Pharma conspiracy to elect Biden.

  7. George
    Posted November 9, 2020 at 7:38 am | Permalink

    Can they give the Nobel Prize to a company? Peace Prize is given to organizations. If Pfizer has actually pulled this off, they, as a company, would deserve it. Pfizer risked $2 billions of its own capital on this project.

    And did you see all the political hacks Biden appointed to his COVID-19 advisory board? Yeah – none. So Biden will treat a public health issue as a public health issue, not a political problem. Imagine that.

    • George
      Posted November 9, 2020 at 8:51 am | Permalink

      I take back everything nice I said. The Pfizer vaccine is a fraud. Their effort is being led by an immigrant – a woman no less. Kathrin Jansen. So what if she previously led the development of the HPV vaccine and pneumococcal vaccine.

      Even worse, Pfizer’s partner, BioNTech, was started by the children of Turkish immigrants to Germany.


      On a more serious note, from Tyler Cowen –
      In seriousness, the expected value of delaying getting sick just went way, way, way up.

    • Filippo
      Posted November 9, 2020 at 10:03 am | Permalink

      “If Pfizer has actually pulled this off, they, as a company, would deserve it. Pfizer risked $2 billions of its own capital on this project.”

      If the company won the Nobel prize, what portion of it would Pfizer researchers get?

      Apparently true that Pfizer has risked $2B up front. Per link below it appears they’ll be reimbursed by the federal government when they meet certain benchmarks of success.


      • Posted November 9, 2020 at 1:23 pm | Permalink

        “they’ll be reimbursed by the federal government when they meet certain benchmarks of success”

        As they should be.

        And if they failed? The majority of drug programs “fail”. Companies won’t take risks unless there is a prospect of reward.

        • Filippo
          Posted November 9, 2020 at 1:44 pm | Permalink

          ‘As they should be.’

          I haven’t said they shouldn’t be. The initial post didn’t mention the prospective reimbursement, giving the impression that the risk was solely Pfizer’s alone.

          ‘Companies won’t take risks unless there is a prospect of reward.’

          Yes, that is the reality. Hence, for example, the Rural Electrification Act of 1936.

          • Posted November 9, 2020 at 2:03 pm | Permalink


            And don’t we have a rural internet act now? Or is that still just a proposal?

  8. ladyatheist
    Posted November 9, 2020 at 7:39 am | Permalink

    I really hope this pans out! Those of us with brains need to be protected from the anti-maskers & anti-vaxxers.

    • Posted November 9, 2020 at 1:31 pm | Permalink

      Here’s something I wrote this morning:

      Very few people in the USA, until COVID, were close witness to anyone dying of a typical communicative disease, such as measles. Hence, in my opinion, the rise of anti-vaccination BS. It’s been too long since an epidemic swept away a tenth or a fourth or a third of the children in someone’s town. This was a commonplace occurrence for our ancestors.

      I think now people are like, It’s just old people, they die anyway. When it sweeps away children, it’s much more impactful.

      Masks were intentionally politicized by Trump because, in his infantile, thin-skinned narcissism, he interprets anything the could reflect badly on him to be a personal attack (everything in the world, after all, is about him, right?).

      Imagine the lives that would have been saved in this counterfactual:


      Donald Trump steps to the microphone at the White House and says to the American people:

      “I have met with my scientific and security teams. They have confirmed that we are in the middle of a great fight: The worst disease to hit our nation and the world in a century. Our lives, our health care system, and our economy are threatened, they sit in the balance. We know little of this emerging threat, we have no vaccine against it, and we have few effective treatments. But our scientific and medical teams are working on it. The CDC and the rest of my scientific and medical teams inform me that the most important things we can all do right now is: Social distance, wear appropriate face masks at all times when you leave your home. I am therefore issuing an executive order for all Americans to wear masks when in public. We must all do this to protect ourselves, our families, and others. This is our moment to show strength, determination, and resilience. I know we can do this together.”

      But what did we get? Lies. Nonsense about injecting disinfectants. Politicization of basic public health measures. Denigration of the hard-working scientists trying to help protect their fellow citizens. Denigration of our health care workers, risking their lives and health to continue to care for us.

      • darrelle
        Posted November 9, 2020 at 2:31 pm | Permalink

        This is one of two or three big problems the Biden administration has in attempting to get a handle on covid at this late date. The well has been well and truly poisoned already by Trump inspiring his supporters, nearly half the nation apparently, to view wearing masks as anywhere from bullshit to persecution and to believe that there are only two choices: do nothing (aka keep the economy open) or absolute lockdown.

        In the US, the only thing that will be effective at getting covid under control any time soon is the possibility of an effective vaccine. It’s too late for any other measures to have a chance. Too many people won’t accept the responsibility and sacrifice it would take to prevent them from contributing to the maiming and killing of some of their fellow citizens.

        • Posted November 9, 2020 at 2:47 pm | Permalink

          Yes, I totally worry about this hurting Biden. If we get a vaccine soon, the Trumpers will claim it for Trump’s Operation Warp Speed. If we don’t, the virus will still kill lots of people for all the reason you state and the Trumpers will say, “See! Biden couldn’t do any better.” He might even do worse if measured in deaths or cases per month.

          • phoffman56
            Posted November 10, 2020 at 6:19 am | Permalink

            Did Pfizer take part (and money) in operation warp speed? A: No.

            You still think Drumpf got you the vaccine?
            Is it the “N”, or is it the “o” you don’t get?

            That’s the answer to those giving Mass Murderer donald credit.

  9. Trevor H
    Posted November 9, 2020 at 7:46 am | Permalink

    A Grauniad link


    Widely shared on facebook, and attracting the usual anti-vax swarm

  10. Randall Schenck
    Posted November 9, 2020 at 7:48 am | Permalink

    I recall way back in the Polio days the vaccine required 3 shots and then another one later on. We got them all and never complained.

    • George
      Posted November 9, 2020 at 7:59 am | Permalink

      Back in the polio days, the attitude to vaccines was – Are there any more shots you can give my kid?

      I was born in 1956. The Sabin vaccine came out in 1952, mass vaccination started in 1955. There were problems. The Sabin vaccine became widely available in 1961. The US was still committed to the Salk vaccine so Sabin and Koprowski tested it on ten million children in the USSR in 1959. It was a huge success. Wikipedia has a good history on it:

      Hard to describe the terro and fear that existed around polio. If we get a good vaccine less than a year after this virus emerged, that is truly remarkable.

    • Posted November 9, 2020 at 8:12 am | Permalink

      I’m still ticked about the three shots. Our doctor had a really mean nurse who apparently hated kids. She was known for inflicting as much pain when giving shots as possible. The doctor had a condition that made his hands shake, so you didn’t want him to give you a shot either. Anyway, after the third shot, the new polio vaccine was introduced: administered on a sugar cube.

      • Randall Schenck
        Posted November 9, 2020 at 8:31 am | Permalink

        Having been in the service shots are something you get over pretty fast. The guns were real popular back then, although I think they no longer use them. They had double barrel guns and they sometimes would get you in both arms at the same time.

        • merilee
          Posted November 9, 2020 at 8:43 am | Permalink

          I remember flying from California to West Africa in ‘72 or so. To visit my parents. Two long flights. One gamma globulin shot in each “cheek” plus a cholera shot which really made me feel rotten. Could not get comfortable. And then a yellow fever shot when I got there. Just recently had reactions to the first shingrex shot plus the double dose flu shot (chills, chattering teeth, etc.). Doc says I must have a really good immune system. I rarely do get flu or colds, but this year it seems especially important to be on the safe side. Possible great news about the covid vaccine!

        • darrelle
          Posted November 9, 2020 at 2:34 pm | Permalink

          Definitely. The sheer number of shots you were subjected to in the 70s when you were stationed overseas was daunting. After several days of numerous shots in both arms I could barely lift them.

      • Hempenstein
        Posted November 9, 2020 at 10:01 am | Permalink

        I swear, they have gotten better at sharpening needles since I was a kid in the ’50s. The last flu shot I got, last month, I absolutely did not feel a thing. Even last year I still felt a little bit.

        • merilee
          Posted November 9, 2020 at 10:03 am | Permalink

          Agree. I didn’t feel my flu shot going in at all (and it was way up near my shoulder.) just 12 hours later…

        • Mark R.
          Posted November 9, 2020 at 12:22 pm | Permalink

          I usually get the flu shot at my doctor’s office, but this year got it done at a pharmacy because it was closer and I wanted to avoid doctor offices because of Covid. My wife and I got them at the same time by the same pharmacist. It was the first shot in years that actually hurt. My wife also said it hurt. What’s worse, a week later, both are arms still hurt and my wife could barely lift her arm. We did some research, and diagnosed ourselves as getting SIRVA: shoulder injury related to vaccine administration. The shoulder pain is finally going away- it took a couple months. Crazy, never knew about the syndrome. Next shot will be at the doctor’s office. 😉

        • Posted November 9, 2020 at 1:35 pm | Permalink

          They have. I work in medical device industry. But it takes individual attention from the designer and the procurement people …

          • darrelle
            Posted November 9, 2020 at 2:41 pm | Permalink

            I had blood drawn today for a routine physical and for the first time ever in my experience I didn’t feel anything when the nurse slipped the needle in. I was impressed.

            When I was young I didn’t mind shots at all. Somehow as I aged I’ve steadily become a wimp. Last year my daughter held my hand as I got my flu shot because I was so anxious. This year I had to do it alone!

            • merilee
              Posted November 9, 2020 at 2:43 pm | Permalink

              You musta put on your big boy pants🤓

              • darrelle
                Posted November 9, 2020 at 2:46 pm | Permalink

                I’m tell’n ya, It was tough!

              • merilee
                Posted November 9, 2020 at 2:48 pm | Permalink


            • Posted November 9, 2020 at 2:50 pm | Permalink

              Sometimes the needle slips past all the nerve endings. Truly the luck of the draw! I remember accidentally driving the pointy end of a large safety pin about an inch into my knee. I felt only a small tug on the skin and no pain at all. I just pulled it straight out and it didn’t even bleed.

              • darrelle
                Posted November 9, 2020 at 3:42 pm | Permalink

                Yeah, it’s funny how that works. I’ve had a tiny prick in just the wrong spot hurt like the dickens, but then a stab with a very sharp knife to my inner thigh and I barely felt a thing.

              • Posted November 9, 2020 at 4:47 pm | Permalink

                Be careful, that’s Hannibal Lecter territory!

  11. Alexander
    Posted November 9, 2020 at 7:56 am | Permalink

    I think this was a wise move by Pfizer. An earlier announcement would have resulted in Trump screaming that this was *his* vaccine and that he earned all the praise for its development.

  12. GBJames
    Posted November 9, 2020 at 8:41 am | Permalink

    Good news, indeed. The timing of this announcement is going to enrage tRump.

    • merilee
      Posted November 9, 2020 at 8:46 am | Permalink

      I will be sooooo happy when I can stop muttering “effing moron”. My semi-Repub brother (hates Trump) quipped that it ain’t over till the fat guy goes to Sing-Sing.

  13. Charles A Sawicki
    Posted November 9, 2020 at 8:57 am | Permalink

    Hopeful, but very small numbers to be very significant.

    • Posted November 9, 2020 at 1:40 pm | Permalink

      44,000 sample size in a Phase 3 human trial?

      That’s seems like a lot of statistical power to me. I’m used to sample sizes in the scores or hundreds for making quality system decisions.

      Seems to me that the main remaining questions are: Longitudinal data (we knew we wouldn’t have this and it’s a risk worth taking, given the spread and death rate of COVID-19) (and maybe data on different genetic cohorts/groups) and how long before the virus mutates to the point of making the immunity ineffective.

      So far, from everything I’ve heard on the (massive) DNA sequencing being done on COVID-19, it’s not looking like the flu on this score. Thank goodness.

  14. Posted November 9, 2020 at 9:01 am | Permalink

    Lots of ifs & buts.

    Who do you give it to first? In which countries?

    Only 90% effectiveness so not going to stop the need for social distance or masks.

    Has to be stored very cold – below -80C.

    Etc etc

    • jezgrove
      Posted November 9, 2020 at 12:11 pm | Permalink

      Yup, it’s good news but not “game over” by any means .

    • Posted November 9, 2020 at 1:42 pm | Permalink

      90% effectiveness, assuming everyone is vaccinated, would likely deliver herd immunity.

      Of course, we don’t know yet. And Trump’s bungling and the anti-vaxx crowd may discourage too many people from getting vaccinated. And of course, a vaccination program will take time.

      • Hempenstein
        Posted November 9, 2020 at 3:09 pm | Permalink

        A micro-chip or some other thing that could not be faked/forged, given to someone else that would allow entry to bars etc would go a long way toward greater compliance Of course the wingnuts will scream Bill Gates, but never mind.

  15. Posted November 9, 2020 at 9:07 am | Permalink

    The founders of the BioNTech company are, BTW, both children of immigrants (Turkish ‘guest workers’) to Germany. (Germany country screws up ‘integration’ pretty stupidly in many ways, so it’s good to see such a spectacular success story.)

  16. Posted November 9, 2020 at 9:42 am | Permalink

    I can’t help imagining that the head of Pfizer (Mr. Pfizer?) is a democrat and waited till after the election to announce the good news.

  17. Hempenstein
    Posted November 9, 2020 at 9:55 am | Permalink

    I’ve forgotten Pfizer’s is based on. RNA to the whole spike protein? Moderna’s is a RNA tinkered (a couple of proline substitutions to stabilize the resultant peptide) sequence corresponding to a segment of the spike is the only one I remember for sure.

    The thing I wonder is whether, once more than one vaccine is approves, whether it might provide a further leg up to get two based on different aspects of the virus, or whether there might be some risk of triggering a big reaction on receipt of the second one, depending.

    Some of us, like protein biochemists such as me who only know enough immunology to be dangerous, are going to learn more as this goes on, anyway.

    • George
      Posted November 9, 2020 at 10:43 am | Permalink

      Overlooked in all the elation is that there are still ten more vaccines under development. So even if this one does not pan out, we have more chances.

      • Posted November 9, 2020 at 1:44 pm | Permalink

        Yes, many “shots on goal” as we say at the company I work for.

        And his disease has greater focus and motivation than any in his lifetime according to Francis Collins.

      • Torbjörn Larsson
        Posted November 9, 2020 at 4:27 pm | Permalink

        We’ll need them – this vaccine type need freezers, so is expensive to disseminate globally.

  18. Posted November 9, 2020 at 11:32 am | Permalink

    This is good news but it may be even better news for vaccines other than Pfizer’s. Pfizer’s vaccine requires two shots and has somewhat difficult requirements for transportation. They are also not part of the fed’s Operation Warp Speed so I’m guessing that this means it will cost a lot for each vaccination. Although this is good news for the stock market, I’m guessing it will be a while before we can all get vaccinated and resume our normal lives in pre-pandemic mode.

    • Posted November 9, 2020 at 1:46 pm | Permalink

      Widespread vaccination? End of Q2 2021, best case. End of 2021 more likely.

      Given that we have no vaccine now and precious little in the way of treatment and the high death rate, boosters and transport are small quibbles.

      • Posted November 9, 2020 at 2:34 pm | Permalink

        They are small quibbles but they all contribute to slow down the arrival of a vaccination. It also may mean that Pfizer isn’t the eventual winner, which also slows things down.

  19. Ugo Corda
    Posted November 9, 2020 at 11:46 am | Permalink

    The next question is: for how long will the vaccine be effective?

    Antibodies have been shown to disappear in a couple of months. So at that point we’ll have to rely on memory cells to regenerate the antibodies at the time of a new infection. Will the immune system behave as it is supposed at that time, or will this infection undermine its normal functioning?

    I imagine that Phase III has been too short in duration to be able to provide that kind of responses

  20. enl
    Posted November 9, 2020 at 11:52 am | Permalink

    I will note that the official press release made it clear that it was not Pfizer, but D J Trump that was responsible for this:


    Oh, wait, no. That was a BS claim by a political hack.


    Unfortunately, the song remains the same…

    • Blue
      Posted November 9, 2020 at 12:35 pm | Permalink

      Dr Jansen’s Pfizer boss is its Chairman and CEO,
      Albert Bourla, D V M, PhD.

      Informed Dr Bourla IS by his DVM – ness /
      by his / their work upon … … animals
      .other than. humans.


  21. Mark R.
    Posted November 9, 2020 at 12:23 pm | Permalink

    Biden winning POTUS was a huge relief, and so is this. 2020 still sucks, but at least there are some bright spots.

    • Posted November 9, 2020 at 1:49 pm | Permalink

      Light at the end of the tunnel.

  22. Torbjörn Larsson
    Posted November 9, 2020 at 4:22 pm | Permalink

    If these new, fast mRNA vaccines work, it would be fantastic!

    A note of concern is that the protocol demanded a positive test – we don’t know if it works on asymptomatic infection.

    Not so good, the need for freezers.

    • Hempenstein
      Posted November 9, 2020 at 6:47 pm | Permalink

      FWIW, if it helps, U Pittsburgh is one of the medical centers participating in clinical trials of COVID vaccines. I know they enrolled participants in the Moderna vaccine because a colleague got a shot – I signed up but wasn’t selected because I’m not at sufficient risk by my low contact with others – but he is tested periodically for presence of circulating antibodies etc. So they don’t just give the shots, sit back and see who gets it. I expect that any asymtomatic carriers would be detected in this process.

      Last I heard, a couple days ago, they’re now doing trials with the J&J vaccine. Not sure if they were ever a Pfizer site. If not, it may have to do with Pfizer not being wrapped up in Warp Speed, but this is only a retrospective thought since Pfizer did this one on their own.

  23. phoffman56
    Posted November 10, 2020 at 6:47 am | Permalink

    “More than 90% of the cases were in people who had been given a placebo.”

    This quote SEEMS to imply that statement to be all that is meant by being ‘more than 90% effective’.

    “I believe that 50% effectiveness is the threshold for FDA approval.”

    This has definitely been said by people involved in trying to explain what a ‘positive for the vaccine’ test result is.

    However, with the latter and if ‘meant’ above is correct, all that 50% would mean was that, e.g. if you had a huge trial and 1000 cases occurred, then at least 501 of them were ones given the placebo, and possibly as many as 499 of those sickness cases got the vaccine. That would seem ridiculous as a vindication of the vaccine, unless we were willing to wait a very long time to get to herd immunity.

    So surely ‘more than 90% effective’ has some different and stronger statistical meaning which somebody in experimental science here can explain. Or else the 90% and 50% refer to different things.

    I’m sure in any case that this is very good news. It sounds like 94 cases of which 8 had been given the vaccine and 86 the placebo. From that I’d think that if they’d accidentally given everyone the vaccine, then only about 16 cases would have occurred.
    And if accidentally everybody got the placebo, around twice 86, i.e. 172 people would have got sick. That sure does sound good.

    But the 50% must have a different meaning.

    • phoffman56
      Posted November 11, 2020 at 4:17 am | Permalink

      I was being stupid there, though the first quote is misleading slightly.

      More than 50% effective wouldn’t say just that less than 50% of the sickness cases were vaccinated subjects, i.e. more than 50% were ‘placebo-ed’. It presumably would say that more than 2/3 were, so less than 1/3 were vaccinated subjects. It’s the 1 and 2 numerators that says less than 50%. So my example at the end would say at most 333 vaccinated, so at least 667 ‘placebo-ed’, making them add up to 1000, far more reasonable.

      This is much simpler than any mathematical statistics being involved. Because 90 is so much closer to 100, my guess of 94 and 8 should have been 94 and 7 (even better! but close to the same), since 8/86 isn’t less than 1/10, whereas 7/87 is.

      I imagine somewhere somebody in the know about the actual numbers said 87 and 7, rather than just 94 and 90%.

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