Posted on 11/12/2021 9:53:27 AM PST by ProtectOurFreedom
(This is from Dr. Campbell's YouTube description) New Pfizer antiviral and ivermectin, a pharmacodynamic analysis
New Pfizer antiviral, PF-07321332, C₂₃H₃₂F₃N₅O₄
PF-07321332 is designed to block the activity of the SARS-CoV-2-3CL protease,
(Excerpt) Read more at youtube.com ...
It seems to me clinical trials can show if a drug is effective against disease in the real world but won't necessarily identify the mechanism the drug uses.
The trial may show ivermectin to be an effective anti-viral but whether that's because it's a protease inhibitor or something else would be answered in the lab or by modeling.
RE: It seems to me clinical trials can show if a drug is effective against disease in the real world but won’t necessarily identify the mechanism
the drug uses
If Pfizer can, by clinical trial, determine that its drug works as a protease inhibitor, why can’t a similar trial be used to determine if Ivermectin can also act the same way given the in vitro and modeling studies do show this?
The question is are there clinical studies showing it's a protease inhibitor.
I haven't seen any.
RE: Meaning let’s slow down on making claims we don’t have evidence for.
OK, as long as “slow down” does not mean stop physicians from prescribing Ivermectin for Covid as they see fit, I’m all for a cautious approach to studying Ivermectin’s mechanisms in fight the Coronavirus.
What makes you think they determined that by clinical trial?
I'd think their scientists would identify a compound that should function as a protease inhibitor, verify that action in the lab or a model (like the studies you posted), and then conduct clinical trials to see if that action was effective fighting the virus in people.
Clinical trials are very late in the drug development process. Long after the expected mechanism of action has been identified.
“ answered in the lab or by modeling”
Hence the “in silico” modeling that’s going on.
Ok, so you’re saying that the claim that Pfizer’s drug is a Protease inhibitor has not been proven in a clinical trial?
Right, because that's not what clinical trials do.
As I understand it protease inhibitors are developed via molecular engineering. Compounds are designed to bind to specific viral enzymes which in turn disrupts viral replication.
They are synthetic compounds targeted at a specific enzyme.
These compounds are then evaluated in the lab to see if they do as intended, and if so they are probably tested in animals.
At some point there will be clinical trials but the fact that the compound is a protease inhibitor was established long ago.
Now just because something works in the lab (in vitro) doesn't mean it's going to be effective in humans in the real world. That's what clinical trials are for.
Pfizer knows whether a drug is a protease inhibitor or not without doing clinical trials.
A trial tells them that the drug is effective fighting a disease.
RE: Now just because something works in the lab (in vitro) doesn’t mean it’s going to be effective in humans in the real world. That’s what clinical trials are for.
Pfizer knows whether a drug is a protease inhibitor or not without doing clinical trials.
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And how does Pfizer know that?
Isn’t it because they evaluated these compounds in the lab IN ADVANCE and found out that they indeed showed Protease inhibition capabilities? Didn’t they also use computational modeling for this?
Then the next question arises — granted that Ivermectin was NOT originally developed for Covid, but was eventually found via lab observation to exploit protein targets from both virus and human ( as per the NIH study), which could be the reason behind its excellent in vitro efficacy against SARS-CoV-2, and also given that Ivermectin, in computational models, efficiently utilizes viral spike protein, main protease, replicase and human TMPRSS2 receptors as the most possible targets for executing its antiviral efficiency, why then is it appropriate to call Pfizer’s drug a Protease inhibitor but not Ivermectin?
This is especially so given that the NIH found (COPY AND PASTE FROM THEIR STUDY ) :
* The pharmacokinetic attributes of ivermectin were compared with other two anti-SARS-CoV-2 drugs and ivermectin was found to be a safe drug.
* Ivermectin was found to be an efficient inhibitor of Mpro, replicase and hTMPRSS2 and the study manifests a superior ground for the candidature of ivermectin to be an efficient anti-SARS-CoV-2 therapeutic option.
* IVM utilizes viral spike protein, main protease, replicase, and human TMPRSS2 receptors as the most possible targets for executing its antiviral efficiency by disrupting binding
I imagine they did, yes.
...why then is it appropriate to call Pfizer’s drug a Protease inhibitor but not Ivermectin?
I'm not saying ivermectin isn't a protease inhibitor - I don't know either way - all I've said is I haven't seen any clinical studies that say it is. Which is what you claimed.
This is not my feed at all (I’m a mechanical engineer), but my understanding is that clinical trials are not going to reveal the method of action of a drug. They will only tell you if a drug is effective at achieving a defined end point of the trial.
Lab studies will reveal the pharmacokinetic and pharmacodynamic actions at the molecular level.
Exactly. Just like a road test won't give you the molecular makeup of the hydrocarbon you're burning, just let you know if it will make your car go Vroooom.
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