The latest Investing Matters Podcast episode featuring Jeremy Skillington, CEO of Poolbeg Pharma has just been released. Listen here.
OMG! Bug*** me. I was posting about neutralising antibodies yesterday and see posts during last night from others and from stanman himself (haha) at 05:36 !!! I woke up early -wierd.
This firm could be developing into a blockbuster, I kid you not. Exciting+++.
RorkesDrift - Thanks for the link to the Univ of Leicester article.
I do agree with jiffybag's comments.
In fact, the intense & worldwide research into all things COVID-19 at the moment could have medical and therapeutic long-term implications in all sorts of directions - from respirators to treatments and infecfious disease prevention.
I had wondered whether the binding properties of affimers could be used directly & therapeutically in some way so I'm fascinated to learn from contributors to this thread to read of the type of work being done at Leicester and Cambridge Uni's.
Might we see a third branch of the UK Avacta facilities some time? Ha!
BigBiteMore - You say : "Its important to keep one's feet on the ground and take things step by step ….."
I could not agree more. It bothers me when 'investors' start talking about loans, max-ing out on credit cards etc in order to significantly increase an AVCT holding. I am as confident as I can dare to be about a good outcome here, but relatively few AIM companies succeed in reaching the glorious heights despite all the promise and hype they produce on the way. Most do not, or even worse.
Never wrong to take a profit, even if you leave something on the table.
I do accept that we live in exceptional times just at the moment and good times may well be a-comin'. Just take care here folks.
Undoubtedly the Roche serological antibody test with its claimed 99.8% accuracy is a major step forward, especially for epidemiological purposes. It can be done quickly in many labs, including in the NHS, who will already have the automated equipment to run the tests as such kit has been used for many other routine tests for years.
One issue at the moment is that nobody knows whether the antibodies to COVID-19 that are produced in response to infection ae truly protective or not.
This may be because antibodies can be "binding" or "neutralising". Binding antibodies do that -bind to the antigen. They do not, by definition, neutralise it. Neutralising antibodies do just that. So we do not yet know whether COVID-19 antibodies are typically neutralising, or just binding. If you are a betting man though, you would favour at least in part the former.
This I think is the main reason why most authorities are saying at the moment that it is unclear as to what extent antibody production confers protection.
Also just now nobody knows how long any neutralising antibodies last - Months? Years? A lifetime?
That really depends on the type of immunity that this coronavirus type invokes.
Roche test -
Coronavirus antibody test a 'positive development'
https://www.bbc.co.uk/news/health-52656808
"Roche is understood to be in talks with the Department of Health and Social Care about possible use by the NHS in England, though other testing products are also being assessed."
SiriusB - you say "Thanks for sharing RapidSequence. Very interesting. ‘False positives’ against the ‘gold standard’ PCR test would be a very interesting development if they are then proven to be correct."
I agree that would indeed! It seems to me that PCR is regarded as "the gold standard" at the moment, but it is certainly 'gold' with a lower-case 'g'. I suppose it is the best we have at the moment. I wonder what the "limit of detection" of SARS-Cov 2 by PCR is? Have you seen any data on this?
Any apparent "false positive" subjects for say Avacta's antigen test ideally should be followed to see what proportion actually turned out to be "true positives". That is one reason why exhaustive clinical validation can take a long-ish time, and because of the present urgency I guess this degree of detail may be spared.
Having said all that though, perhaps the main reason for Avacta "false positives" might simply be the inadequacy of poorly taken swab samples.
Thanks Ophidian for your post of 23.13 with the link to the FDA stuff. I did not read it all (!!) but I did read section J on the LOD stuff as you suggested.
I am pleased to see that it is still defined (in so many words) as the amount that can be distinguished with 95% certainty from zero.
So I guess one needs to prepare samples of virus with decreasing dilutions of virus, and then test them.
Interestingly this was the original definition of LOD used in the very early days of immunoassay (then radioimmunoassay) over 60 years ago for which two Americans, Ros Yallow & Sol Berson, were awarded the Nobel Prize. That technology brought highly sensitive assays to many diagnostic laboratories and revolutionised clinical endocrinology.
The technique has been hugely diversified since that era, and has many other important areas of clinical use.
You and others are likely completely bored by all of this, but it took me back to early days in the clinical science of this in the 1970's !
And here we are now with a bit of vital virology. Love it!!
Thanks again for putting up the whole FDA submission link. What a tortuous business it is now. Good luck to Avacta where submission application will keep a few PhD's busy for a few days!
https://www.yorkshirepost.co.uk/business/wetherby-based-avacta-begins-shipping-virus-testing-kits-2848576
https://uk.reuters.com/article/brief-avacta-group-ships-sars-cov-2-affi/brief-avacta-group-ships-sars-cov-2-affimer-reagents-to-cytiva-and-adeptrix-idUKFWN2CT010
https://www.labmate-online.com/news/mass-spectrometry-and-spectroscopy/41/avacta-group/covid-19-antigen-diagnostic-collaboration-announced/52233
All grist to the mill, eh?
This seems like a potential compeptitor. POC antigen test.
https://www.telegraph.co.uk/business/2020/05/10/uk-dutch-startup-secures-funding-instant-result-coronavirus/
https://cardusocapital.com/carduso-capital-finances-the-groningen-virotact-that-is-developing-a-rapid-point-of-care-covid-19-test-for-the-immediate-detection-of-corona-contamination/
https://www.detactdiagnostics.com/virotact/
"Carriers could get a negative test result, Government admits"
An extract in this article reads :
'The quality of home testing kits has also been thrown into question after it emerged that the instructions for thousands of those sent out were riddled with errors.
A six-page {?sic!] set of instructions setting out how to swab the nose and throat, and return the sample to labs, wrongly labels three of the seven elements posted out to recipients.
The blunders follow warnings from experts that those without training in swabbing may make errors'.
So c'mon Avacta - let's be having you !!
Ophidian - the answer is yes. The virus can be spread by persons in the pre-symptomatic phase, some of whom may not later develop symptoms at all - I think that is the question you are asking?
Also whether a given infectious dose of virus gives rise to disease or not, and if it does the disease severity, likely depends not only on the "infectious dose" but also on the adequacy of the recipient's immune system. And that for example declines naturally with advancing years as we all well know by now.
Although conclusive data is somewhat lacking for COVID-19 at the moment, it does seem that disease severity is related to "viral load" - the amount of virus per unit volume - (saliva, lung secretion or whatever).
The terms "infectious dose" and "viral load" are distinct entities meaning different things although they seem to be used interchangeably by some folk.
Finally, although I am a doctor (or rather was!) I have no specialist knowledge re infectious disease, so I'm always open to corrections by those who are!
Ophidia - that's not quite right.
"In medical diagnosis, test sensitivity is the ability of a test to correctly identify those with the disease (true positive rate), whereas test specificity is the ability of the test to correctly identify those without the disease (true negative rate)."
Further information here, for example:
https://www.healthnewsreview.org/toolkit/tips-for-understanding-studies/understanding-medical-tests-sensitivity-specificity-and-positive-predictive-value/
LOD can be regarded as an aspect of defining sensitivity. Both terms can be used to help define performance of qualitative assays.
Be assured that the news this morning means that this assay will show enhanced sensitivity as a result of the use of 2 antibodies.
Now if their use can be combined into the same test at the same time - so called "double antibody methodology" that would represent potentially a major step forward in the technology.
Very likely increased specifically as well, as a result of reduction in so called "non-specific binding".
The best - even of the very best.
Good news.
PAH00 - you seem to know a little more the chemistry of affimers than I do - not that difficult! Although I am a long retired medically qualified biochemist!!
It is always good to understand as much as possible about companies that one invests in, so may I ask if you know anything about B-steffin- the protein molecule on which affimers are based apparently?
I have done a quick search but can find very little about exactly what B-steffin is and where it is found in humans.
If anyone else can help out them I'm all ears. Thanks, enjoy your w/e folks & stay safe
jonesrichard - yes the antigen test will be absolutely vital - which is why I am here. But I'm sensible (and mature) enough to not regard antibody tests as competing with antigen tests, like some folk seem to do. They are both critical in the battle against covid-19.