Nature article on Coronovac trials in Brazil, Indonesia and Turkey

[cormanr7]

There has been a lot of talk about the widely varying efficacy results of the Coronovac vaccine trials (also ordered by Thailand)  in various countries. Nature has an article that shed some light on this though much remains vague in the absence of extensive, public trial data:

https://www.nature.com/articles/d41586-021-00094-z

 

There are obvious problems: data from the Indonesian ( 65.3% claimed efficacy) and Turkish trial (91.3%) were obtained from a small number of participants with a low number of COVID infections (25 and 29, respectively) which is far too low for a reliable estimate. The Brazilian trial (50.6% efficacy) was much larger but there are questions about the dose interval: this was taken as two weeks, though earlier trials in China showed that better results were obtained with a four week interval. You can read the rest for yourself.

 

Now most people have been shouting that the Chinese products are <deleted>. I don't know but I think there is a potential other important factor. The Coronovac vaccine uses inactivated virus. Various reviews suggest that such vaccines often lead to poor immunogenicity and require multiple doses (e.g. Rabies vaccine requires three doses for maximal protection). This may be due to damage/change in structure of the virus during the activation either by formaldehyde or heat. Hence it will be interesting to see the results of an inactivated virus vaccine under development by Valneva (a French drug company) . Unfortunately phase III trials are only just about to start so early results won't be available till April.

 

Finally those who think that administering poorly documented/unproven vaccines (e.g. without extensive phase III trial data) on a large scale is limited to China and Russia think again. The inactive virus vaccine from Bharat Biotech (Covaxin) is now administered in India (together with the licensed stuff from AZ)  though the phase III trial is still in progress. Interestingly, the company just announced that they will pay compensation if the vaccine causes serious side effects.

 

 https://www.thehindubusinessline.com/news/bharat-biotech-to-pay-compensation-if-covaxin-causes-side-effects/article33587604.ece

[Mavideol]

8 minutes ago, cormanr7 said:

There has been a lot of talk about the widely varying efficacy results of the Coronovac vaccine trials (also ordered by Thailand)  in various countries. Nature has an article that shed some light on this though much remains vague in the absence of extensive, public trial data:

https://www.nature.com/articles/d41586-021-00094-z

There are obvious problems: data from the Indonesian ( 65.3% claimed efficacy) and Turkish trial (91.3%) were obtained from a small number of participants with a low number of COVID infections (25 and 29, respectively) which is far too low for a reliable estimate. The Brazilian trial (50.6% efficacy) was much larger but there are questions about the dose interval: this was taken as two weeks, though earlier trials in China showed that better results were obtained with a four week interval. You can read the rest for yourself.

Now most people have been shouting that the Chinese products are <deleted>. I don't know but I think there is a potential other important factor. The Coronovac vaccine uses inactivated virus. Various reviews suggest that such vaccines often lead to poor immunogenicity and require multiple doses (e.g. Rabies vaccine requires three doses for maximal protection). This may be due to damage/change in structure of the virus during the activation either by formaldehyde or heat. Hence it will be interesting to see the results of an inactivated virus vaccine under development by Valneva (a French drug company) . Unfortunately phase III trials are only just about to start so early results won't be available till April.

Finally those who think that administering poorly documented/unproven vaccines (e.g. without extensive phase III trial data) on a large scale is limited to China and Russia think again. The inactive virus vaccine from Bharat Biotech (Covaxin) is now administered in India (together with the licensed stuff from AZ)  though the phase III trial is still in progress. Interestingly, the company just announced that they will pay compensation if the vaccine causes serious side effects. https://www.thehindubusinessline.com/news/bharat-biotech-to-pay-compensation-if-covaxin-causes-side-effects/article33587604.ece

by any chance do you have any interest (financial/personal or other)  in the Chinese products

[internationalism]

Astrazeneca is still in phase 2/3 trial, but aproved for an emergency. The rest of aproved are also at phase 3 and without known efficacy. 
so it’s entirely to health authorities in each country, depending on availability

Edited January 18, 2021 by internationalism

[rabas]

1 hour ago, cormanr7 said:

There has been a lot of talk about the widely varying efficacy results of the Coronovac vaccine trials (also ordered by Thailand)  in various countries. Nature has an article that shed some light on this though much remains vague in the absence of extensive, public trial data:

https://www.nature.com/articles/d41586-021-00094-z

There are obvious problems: data from the Indonesian ( 65.3% claimed efficacy) and Turkish trial (91.3%) were obtained from a small number of participants with a low number of COVID infections (25 and 29, respectively) which is far too low for a reliable estimate. The Brazilian trial (50.6% efficacy) was much larger but there are questions about the dose interval: this was taken as two weeks, though earlier trials in China showed that better results were obtained with a four week interval. You can read the rest for yourself.

Now most people have been shouting that the Chinese products are <deleted>. I don't know but I think there is a potential other important factor. The Coronovac vaccine uses inactivated virus. Various reviews suggest that such vaccines often lead to poor immunogenicity and require multiple doses (e.g. Rabies vaccine requires three doses for maximal protection). This may be due to damage/change in structure of the virus during the activation either by formaldehyde or heat. Hence it will be interesting to see the results of an inactivated virus vaccine under development by Valneva (a French drug company) . Unfortunately phase III trials are only just about to start so early results won't be available till April.

Finally those who think that administering poorly documented/unproven vaccines (e.g. without extensive phase III trial data) on a large scale is limited to China and Russia think again. The inactive virus vaccine from Bharat Biotech (Covaxin) is now administered in India (together with the licensed stuff from AZ)  though the phase III trial is still in progress. Interestingly, the company just announced that they will pay compensation if the vaccine causes serious side effects. https://www.thehindubusinessline.com/news/bharat-biotech-to-pay-compensation-if-covaxin-causes-side-effects/article33587604.ece

 

Raising India as a single example does not negate China's extreme lack of transparency and independent regulatory control. India is also a democracy with independent regulators and is the world's largest vaccine manufacturer. Apples and oranges.

 

Yes, inactivated vaccines have certain disadvantages. I don't see that casts China's vaccine in a better light. These vaccines are noted for much weaker immune responses requiring multiple shots, boosters, and probably longer development and trials to get things right.

 

The nature article you quoted also gave an alternative reason for Brazil's lower efficacy, that it only included medical professionals who are more likely to report accurately. I.e., a larger,  better trial.

 

Edited January 18, 2021 by rabas

[cormanr7]

2 hours ago, rabas said:

India is also a democracy with independent regulators and is the world's largest vaccine manufacturer.

It was not a coincidence that PM Modi announced approval of two 'indigenous' vaccines (a bit rich as one is the AZ vaccine produced by the Indian Serum Institute, the other the Bharat vaccine)  at the same day. Many feel that nationalism played a major role in this decision and that the the nod to the Bharat vaccine is premature, especially as approval was apparently granted based on unproven claims that it would be effective against the 'English' (B.1.1.7) mutant. There is unease among some health officials in India about the murky proceedings as noted, for instance, in this article https://apnews.com/article/asia-pacific-clinical-trials-india-coronavirus-pandemic-coronavirus-vaccine-16a4c1cfb1b6b5def70812e638e5fc54. 

Interesting side note as already mentioned above is that for the Bharat vaccine, those who receive it need to sign a consent form -which also mentions compensation in case of severe adverse effects- that states that ' has been allowed by the government in clinical trial mode' https://www.thehindu.com/news/ national/coronavirus-bharat-biotech-to-pay-compensation-if-covaxin-vaccine-causes-side-effects/article33587377.ece.

 

We'll see, Bharat data should be available by March.

[rabas]

40 minutes ago, cormanr7 said:

It was not a coincidence that PM Modi announced approval of two 'indigenous' vaccines (a bit rich as one is the AZ vaccine produced by the Indian Serum Institute, the other the Bharat vaccine)  at the same day. Many feel that nationalism played a major role in this decision and that the the nod to the Bharat vaccine is premature, especially as approval was apparently granted based on unproven claims that it would be effective against the 'English' (B.1.1.7) mutant. There is unease among some health officials in India about the murky proceedings as noted, for instance, in this article https://apnews.com/article/asia-pacific-clinical-trials-india-coronavirus-pandemic-coronavirus-vaccine-16a4c1cfb1b6b5def70812e638e5fc54. 

Interesting side note as already mentioned above is that for the Bharat vaccine, those who receive it need to sign a consent form -which also mentions compensation in case of severe adverse effects- that states that ' has been allowed by the government in clinical trial mode' https://www.thehindu.com/news/ national/coronavirus-bharat-biotech-to-pay-compensation-if-covaxin-vaccine-causes-side-effects/article33587377.ece.

 

We'll see, Bharat data should be available by March.

 

Your argument makes my point, exactly.  That Indian medical professionals are fully aware and can make appropriate decisions is precisely what can't happen with China's vaccine.

 

Your reference doesn't discuss B.1.1.7.  However, the even newer Brazilian P.1 mutation is likely a bigger concern because it's attacking previously hard hit areas that should already have good immunity.  P.1 may be getting around those defences. This will only increase the Brazilian authorities already significant concerns about the weaker Chinese vaccine.

 

Here is some worrisome reading.  https://www.sciencemag.org/news/2021/01/new-coronavirus-variants-could-cause-more-reinfections-require-updated-vaccines

 

With so many newer significant mutations, the emphasis should be on the strongest vaccines.