Hacker News new | past | comments | ask | show | jobs | submit login

FYI it’s the same study as the previous news about this, as in the same 2000 individuals study with no severe cases (hospitalization) or deaths in either group and very wide margins for confidence.

This is just the actual paper rather than the leaked abstract from a few weeks ago.

They commissioned a new study to assess the efficacy more precisely especially for severe cases.




I seriously don't understand this.

How does J&J vaccine offer 50%+ protection, but AZ does not?

Don't they use the same technology?

Don't they target the same spike protein?


AZ tested every patient weekly for covid, regardless of self reported symptoms.

No other trial did this. Which means the 95% efficacy for phizer/moderna is not actually correct. we have no way of knowing how many were asymptomatic.


> Which means the 95% efficacy for phizer/moderna is not actually correct.

It is correct, it just efficacy against covid-19 disease, not against SARS-CoV-2 infection. Infection and disease are two distinct concepts.


> efficacy against covid-19 disease, not against SARS-CoV-2 infection.

There is no distinction between "disease" and "infection" in medicine. There is asymptomatic infection, mild, serious and fatal. Even then its not as clear cut as that.

We don't yet have clear data on asymptomatic infection for J&J, moderna, phizer or novavax.

I'm not suggesting that we stop jabbing people, quite the opposite. Even if AZ is less effective, roll it the fuck out. The quicker we get 60-70% of people immune, or partially immune, the quicker this shitshow will be over.


> There is no distinction between "disease" and "infection" in medicine.

That's completely false. An infection is an invasion by a foreign pathogen, a disease is a set of observed symptoms[0].

For other examples of infection/disease distinctions, see HIV and AIDS.

[0]: https://www.ncbi.nlm.nih.gov/books/NBK235412/


I have made an in incorrect assertion.

Obviously there is a distinction, auto immune diseases/cancer/congenintal are the overwhelming example.

What I should have said is: that in this instance we are measuring infection. disease is marketing speak.


This is also incorrect. "Prevention of disease" and "prevention of infection" are two related but clinically-distinct objectives for these vaccines. So far, early clinical trials were generally testing the first objective, and less so the second. It is thus not "marketing speak", but precise language about what was actually tested.


> Understanding infection vs. disease

> There's a difference between infection and disease. Infection, often the first step, occurs when bacteria, viruses or other microbes that cause disease enter your body and begin to multiply. Disease occurs when the cells in your body are damaged — as a result of the infection — and signs and symptoms of an illness appear.

https://www.mayoclinic.org/diseases-conditions/infectious-di...


Here is a great read on infectious agents and the differences between infection and disease.

* Infection does not necessarily lead to disease. Infection occurs when viruses, bacteria, or other microbes enter your body and begin to multiply. Disease, which typically happens in a small proportion of infected people, occurs when the cells in your body are damaged as a result of infection, and signs and symptoms of an illness appear.*

https://www.ncbi.nlm.nih.gov/books/NBK209710/


That's a bold claim. Any sources to back it up?


From the Oxford study[1]:

"To test for asymptomatic infections, participants in COV002 in the UK were asked to provide a weekly self-administered nose and throat swab for NAAT testing from 1 week after first vaccination using kits provided by the UK Department of Health and Social Care (DHSC)."

With notes:

"In Brazil, there was no testing plan for asymptomatic infections. In South Africa, asymptomatic infections were detected from swabs obtained at study visits attended, but are not summarised here as there were only a small number of timepoints for detection of these cases."

And you can see results here [2], which includes both symptomatic and asymptomatic cases (if someone could confirm)?

From Pfizer study [3]:

"Confirmed Covid-19 was defined according to the Food and Drug Administration (FDA) criteria as the presence of at least one of the following symptoms: fever, new or increased cough, new or increased shortness of breath, chills, new or increased muscle pain, new loss of taste or smell, sore throat, diarrhea, or vomiting, combined with a respiratory specimen obtained during the symptomatic period or within 4 days before or after it that was positive for SARS-CoV-2 by nucleic acid amplification–based testing, either at the central laboratory or at a local testing facility (using a protocol-defined acceptable test)."

And per their news release [4]:

"Data from this study, including longer term safety, comprehensive information on duration of protection, efficacy against asymptomatic SARS-CoV-2 infection, and safety and immunogenicity in adolescents 12 to 15 years of age will be gathered in the months ahead."

  [1] https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)32661-1/fulltext#cesec100
  [2] https://www.evaluate.com/vantage/articles/news/snippets/astrazeneca-looks-us-data-and-next-gen-vaccine
  [3] https://www.nejm.org/doi/full/10.1056/NEJMoa2034577
  [4] https://www.pfizer.com/news/press-release/press-release-detail/pfizer-and-biontech-announce-publication-results-landmark


I am in a different Astrazeneca vaccine trial in the USA. (Got jabbed in December) I get my blood drawn monthly, and have weekly symptom check ins via smart phone. I do not get tested weekly


Is there a way to detecy COVID-19 infection post vaccination from blood?

I presume you already have a lot of antibodies after vaccination.


Data from Israel suggests that the Pfizer/Biontech vaccine prevents 97% of symptomatic and 94% of asymptomatic cases.

(After the intial trial phases had concluded Pfizer only reported how many symptomatic cases were prevented which might be the "95%" number you have in mind)


Is this the Israel study you're referring to?

https://www.nejm.org/doi/full/10.1056/NEJMoa2101765

Just curious, as I've received the Pfizer/Biontech vaccine.


I think it was more recent than that but I only saw reports about the numbers, not the thing itself.


I assumed every vaccine trial would be testing people regularly. I'm a little shocked if what you're saying is true. Is there not a lot on the line here? Maybe because it was in their interest to hide bad news?


Prevention of severe disease is a perfectly reasonable standard to use to evaluate a vaccine.

Just look at the hospitalization and death rates for old people in the countries with high vaccination rates.


Fair enough, I don't mean to discount the value of the metrics they did use. However I can think of two things that could be gained from testing people weekly.

1) If it actually prevents detectable infection altogether, it's some evidence of preventing spread, sooner. (as I understand we have some of that evidence now that it's in wide use)

2) If there are long term effects of even asymptomatic cases, we'd have some reason to believe that those are mitigated as well.


These are for-profit companies shielded from liability. They're going to do only the bare minimum to get the product to market.

For other classes of drugs, these same companies have been sued and fined for billions of dollars for covering up problems with their drugs.

The regulators are beyond incompetent, they're typically industry shills.


What evidence are you basing this on?



The fact that the regulators have only issued Emergency Use Authorization for the vaccines shows that less than the bare minimum has been done to bring these products to market. The bare minimum used to be FDA Approval.


If "used to be" counts, then the bare minimum is whatever it takes to get someone to pay for it, like in the literal snake oil days.

It is such a weird stance, implying that it can never make sense for the FDA to change how they do things.


> If "used to be" counts, then the bare minimum is whatever it takes to get someone to pay for it, like in the literal snake oil days.

I’m advocating for higher standards, not lower. With regards to the COVID vaccine, we’ve decreased the quality and quantity of research performed over what we’ve done for previous vaccines.

It sounds like you’re saying that the research on these vaccines is better than before. Which is confusing because they have not obtained FDA Approval. If they had been tested to the same rigor as other vaccines, they would have received this Approval.

> implying that it can never make sense for the FDA to change how they do things.

Again, that’s not what I’m implying. I’m implying that we should change how they do things in only one direction- more safe. Long term research and vigorous testing.

Not rushed testing who’s new rules are dictated by industry-captured regulators.


Imagine a world where competent regulators require a reasonable commonality of what data is gather across all the different vaccine trials. (Plus whatever extra stuff data they want to gather - a common baseline, not a takeover)

Maybe someday.


It's against a defined endpoint. It's a reasonable one, as a vaccine that prevents severe disease is a lot better than no vaccine.

That people don't bother to understand what they read is a problem of course.


They don't target the exact same protein and they use a different vector.


J&J uses a similar vector adenovirus just the human type instead of the chimp adenovirus.

But yes none of the vaccines use the actual spike protein, they all target slightly different amino acid chains on that protein.


The J&J and AZ vaccines both use a similar viral vector with a modified gene.

They target the same protein but just like with the mRNA vaccine they usually do not encode the entire protein but rather target specific amino acid chains in various regions of interest on the protein itself.

Other differences in the vaccine would be the level and type of immune response generated in general which will be based on the specific viral vector used, dose and regiment, adjuvants etc.

The study which measured the J&J efficacy also used a different methodology to this one.

Overall this is a very limited study and should be taken in context.

Another key part is that the T-cell response for the AZ vaccine group seems to remain intact.

>Although the correlation between antibody response and vaccine efficacy is high, which suggests that the neutralizing antibody response is important, T-cell responses may contribute to protection from Covid-19 even in the presence of lower neutralizing antibody titers.32 In a post hoc analysis reported here, we found that in spike-specific T cells that expanded after vaccination with ChAdOx1 nCoV-19, the majority of antigens and epitopes remained intact in recognition of the B.1.351 variant.

Until we have data on actual severe cases it seems that the AZ vaccine is still effective at preventing hospitalization and deaths. There were also no tracking of non-symptomatic cases in the study so the actual prevalence of infections in either group is unkown.


Thanks, somehow with my software engineering mindset, I thought they somehow just copy&pasted the whole ARN sequence for encoding the spike protein from one virus to the other, and the end result should have been the same, but if its only parts of the S protein, then it makes sense that the outcome will be different.


If you want a software analogy, then I think it's more like using regular expressions to try to match inconsistent data, where new data (which is potentially inconsistent in new and exciting ways) is coming in all the time.


Like a virus scanner.


That’s a pretty good analogy the signature isn’t often not a simple hash of the malware but rather a more fuzzy signature based on core functions that are harder to alter without loss of function.


I don’t know if they even have enough room to encode the entire protein, that said even if they do it’s quite likely better to focus on specific amino acid chains that relate to specific structural areas of the protein that serve a critical function like interfacing with the receptors these aren’t likely to mutate without loss of function and it increases the likelihood of more targeted immune response.

If for example each vaccine selected 30 amino acid chains say 15 common ones and 15 that are varied between vaccines you can end up with vaccines that are more effective against certain mutations than others.

Realistically COVID-19 isn’t going anywhere and it will likely become very much endemic and will require a yearly vaccine especially for risk groups just like influenza.


Well now that casts this in a significantly different light. I have read that T-cell response is much more labor intensive to measure than antibodies, but it seems to not uncommonly tell a very different story.


That is starting to change. The FDA recently authorized Adaptive Biotechnology’s T cell assay. It's still more expensive than an antibody test.

https://www.t-detect.com/


They don't translate the spike protein from the original to the target the same way, they might have minor modifications for stability, etc


Without any knowledge of how vaccines work, it's pretty trivial to determine that there are significant differences between AZ and J&J vaccines; J&J only needs one dose while AZ needs two. That alone implies that there are differences in technology or targeted protein, even if the specifics aren't clear to a non-expert.


There are essentially no differences, except J&J's platform had been successful in an European Phase III trial for an Ebola vaccine, but not the one widely used in the last big outbreak, and Oxford's had an 8 year history of Phase I failures. Both replication deficient adenovirus vectors, with the spike protein spliced in, although maybe significantly different versions of the protein.

The biggest difference is their goals, Oxford was intended to be a regular vaccine, J&J intended to get the very best protection from a single vaccination, with an initial goal of protecting a billion people in 2021, now increased to 3 billion. Besides J&J's press releases and slow but sure development methodology see the difference in their Phase III trial primary endpoints, here's J&J's https://www.jnj.com/coronavirus/ensemble-1-study-protocol:

To demonstrate the efficacy of Ad26.COV2.S in the prevention of molecularly confirmed, moderate to severe/critical coronavirus disease-2019 (COVID-19), as compared to placebo, in SARS-CoV-2 seronegative adults

As in, not stopping people from getting the disease, that's a secondary objective.

AZ/Oxford will be hard to track down because they did several different Phase III trails in even more countries. I'd start with ClinicalTrials.gov, look for Primary Outcome Measures and this is a good search to start with: https://clinicaltrials.gov/ct2/results?term=ChAdOx1&cond=Cov... For the US trial:

The efficacy of 2 IM doses of AZD1222 compared to saline placebo for the prevention of COVID-19

J&J is also doing a 2 dose 8 weeks apart US based Phase III trail to see what that can accomplish.


This article talks about at least one tweak that Pfizer, Moderna and J&J do that AZ doesnt

https://cen.acs.org/pharmaceuticals/vaccines/tiny-tweak-behi...


I've heard this multiple times, but never with a citation. Can you point us at anything? Trying to prove a negative with searches hasn't worked for me so far, and this vaccine is not a good option for me so I haven't trying looking up and parsing its spike protein nucleotide or amino acid sequence.

However all these vaccines you listed coerce a small number of your cells to make spike proteins of whatever sort, which results in bits of them being put on the surface of the cells. I don't know how much of the spike protein gets outside cells, either through direct escape or creation of new viruses, have not looked up the exact details of what J&J and Oxford mean by their viral vectors being replication deficient. That is, they don't produce new viruses that can attack other cells.


Different tech. J&j isn’t an mrna vaccine


Nor is AZ. The Pfizer is one with the mRNA technology.


Pfizer and Moderna use mRNA.


neither of those are astrazeneca


neither is AZ




Join us for AI Startup School this June 16-17 in San Francisco!

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: