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To improve medical trials, justify exclusion criteria

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Re: To improve medical trials, justify exclusion criteria

#41
post #35

Earlier quoted context omitted.

> Obesity is an easily treatable condition. Is it? I thought long-term success rates were very low and that prevalence was increasing all over the globe.

Also a person who has trouble breathing tends to not do significant exercise because they run out of breath too quickly.

While exercise is healthy, it isn't a great way to lose weight. Eating a healthier diet, in particular lower calorie, is how you lose weight.

Re: To improve medical trials, justify exclusion criteria

#42

> Why no smoking? Smoking can be an appetite suppressant: https://www.npr.org/2011/06/09/137085989/the-skinny-on-smoki... > Why no diabetes, given that this is an overweight subject group? Given the goal of intermittent fasting is to get insulin levels low enough that your body burns fat instead of sugar, and based on this article at least IF requires closer monitoring of your diet, maybe they wanted to eliminate a v…

maybe they wanted to eliminate a variable/variables.

There's an even simpler explanation: Fasting can provoke dangerous hypoglycaemia in diabetics. The first priority for trials is the safety of the participants.

Re: To improve medical trials, justify exclusion criteria

#43

Earlier quoted context omitted.

prevalence != difficulty of treatment people's unwillingness to cooperate != difficulty of treatment Asthma also isn't the only condition that is hard to treat in morbidly obese people. For many conditions it will be too late to start paying attention to one's calorie intake, but asthma is one that is survivable in the meantime. Severe discomfort and possible death tends to be a good motivator.

Researchers generally analyze intervention success by intention to treat . If a treatment is telling people to "start paying attention to one's calorie intake," and that doesn't have the desired effect, whatever the reason, I think it's fair to say that intervention isn't useful.

Success rate also isn't the same as difficulty.

It's very easy to fill out a lottery ticket, but success rate is very low.

Success is a boolean condition that often first needs to be defined, while difficulty is a spectrum and a more rigid concept. Really the only complication is subjective vs. objective difficulty (what is objectively difficult may be subjectively easy to someone practiced).

Difficult things require hard skills. Reducing someone's calorie doesn't require any hard skill that I am aware of.

Re: To improve medical trials, justify exclusion criteria

#44
>The FDA approved Tezpire as a breakthrough drug for asthma in December 2021. Tezspire excluded morbidly obese people from their efficacy trials.

This statement is very misleading because morbidly obese people were only excluded from the Phase 2 PATHWAY trial[1] and were not excluded from the larger Phase 3 NAVIGATOR trial[2]. The FDA approved Tezpire based on both trials demonstrating efficacy, not just the PATHWAY trial.

[1] https://clinicaltrials.gov/ct2/show/NCT02054130

[2] https://clinicaltrials.gov/ct2/show/NCT03347279

Re: To improve medical trials, justify exclusion criteria

#45

Earlier quoted context omitted.

Researchers generally analyze intervention success by intention to treat . If a treatment is telling people to "start paying attention to one's calorie intake," and that doesn't have the desired effect, whatever the reason, I think it's fair to say that intervention isn't useful.

Success rate also isn't the same as difficulty. It's very easy to fill out a lottery ticket, but success rate is very low. Success is a boolean condition that often first needs to be defined, while difficulty is a spectrum and a more rigid concept. Really the only complication is subjective vs. objective difficulty (what is objectively difficult may be subjectively easy to someone practiced). Difficult things require…

> Success rate also isn't the same as difficulty.

> It's very easy to fill out a lottery ticket, but success rate is very low.

> Difficult things require hard skills. Reducing someone's calorie doesn't require any hard skill that I am aware of.

I don't really want to engage with those statements other than to say I think morbidly obese people do have quite a hard time losing weight.

Re: To improve medical trials, justify exclusion criteria

#46

Earlier quoted context omitted.

Success rate also isn't the same as difficulty. It's very easy to fill out a lottery ticket, but success rate is very low. Success is a boolean condition that often first needs to be defined, while difficulty is a spectrum and a more rigid concept. Really the only complication is subjective vs. objective difficulty (what is objectively difficult may be subjectively easy to someone practiced). Difficult things require…

> Success rate also isn't the same as difficulty. > It's very easy to fill out a lottery ticket, but success rate is very low. > Difficult things require hard skills. Reducing someone's calorie doesn't require any hard skill that I am aware of. I don't really want to engage with those statements other than to say I think morbidly obese people do have quite a hard time losing weight.

> hard time

With which you mean the process causes discomfort? Probably less so than being asthmatic and/or a host of other things, but yes.

Other than that there can be some psychological issues that make self-controlled treatment subjectively hard or impossible. But then we'd have found another condition that would need to be treated first, getting us back to where we started: Somebody running a study on the efficacy of a diet probably would want to preclude people psychologically unable to stick to it...

Re: To improve medical trials, justify exclusion criteria

#47
post #23
post #12

Earlier quoted context omitted.

Why on Earth did you not bother to look it up before asserting your opinion...? https://www.accessdata.fda.gov/drugsatfda_docs/label/2021/76... Body Weight Based on population pharmacokinetic analysis, higher body weight was associated with lower exposure. However, the effect of body weight on exposure had no meaningful impact on efficacy or safety and does not require dose adjustment. Assuming that grandparent comme…

Both my note and the download you discuss are clear about this. You have linked to the the package insert, not the label, and it clearly states at the very top HIGHLIGHTS OF PRESCRIBING INFORMATION These highlights do not include all the information needed to use TEZSPIRE safely and effectively. See full prescribing information for TEZSPIRE. As I wrote in my comment: > ... this kind of info is on the label (prescribi…

Am I losing my gdmn mind here? You say look at the label not the insert, the FDA will have it. I link you to the FDA's label. The link literally had the word 'label' in it drugsatfda_docs >>> label Inside the document there are 3 things the 'HIGHLIGHTS OF PRESCRIBING INFORMATION', AND the 'FULL PRESCRIBING INFORMATION' AND finally 'PATIENT INFORMATION'

I cite the relevant information about weight from them 'FULL PRESCRIBING INFORMATION: CONTENTS: PART 12 CLINICAL PHARMACOLOGY and you act like I not you have performed some sort of bait and switch...

You are the one claiming expertise here, so enlighten me, where is the the carve out for "we didn't test this at all on the morbidly obese" in place a doctor will find it if not in 'FULL PRESCRIBING INFORMATION'?

Re: To improve medical trials, justify exclusion criteria

#48

Earlier quoted context omitted.

You may not have 10 years to wait if you're dying of some disease.

You dying to a disease is nobody's fault (usually). You dying to a bad drug is arguably someone's fault, and I suppose there are probably not any number of documents you can sign that will completely abdicate the responsibility for your death from the corporation that created the chemical compound that resulted in your demise. And probably for good reason? I really don't want to live in a society that gives people th…

The proper, moral, and correct thing to do is to allow each individual to decide for themselves after being presented with the facts on the risks, probabilities, and benefits.

> I really don't want to live in a society

In a free country, you don't really have the moral authority to make such decisions for other people. After all, you aren't wearing their shoes.

Re: To improve medical trials, justify exclusion criteria

#49
post #29

Earlier quoted context omitted.

How is that questionable? Isolating to one relevant treatment per group is a standard procedure.

It gives study staff the ability to exclude arbitrary sick patients from the trial. Combine this with a little harmless unblinding and the whole study outcome can be fabricated with plausible deniability. Notice that I'm referring exclusively to studies of prophylactics. The patient getting sick is the data point.

But trial arms need to be balanced, so excluding sick patients would stick out like a sore thumb.

Of course you don’t allow patients to seek care elsewhere during a trial. If they went to their doctor and were prescribed some alternative therapy it would ruin all the data from that patient.

Re: To improve medical trials, justify exclusion criteria

#50

Based on the record of the pharmaceutical industry and their entirely captured regulatory agency, the FDA, it's not entirely unwise to wait about ten years after the introduction of a 'breakthrough drug' to see if it actually has negative side effects that were not discovered in the clinical trials. See Vioxx, etc. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC534432/ > "Dr Graham, associate director in the FDA's Offi…

Hilarious how you say companies have entirely captured the regulatory role of the FDA.

Then you say look at Vioxx, which went through a full phase 3 study.

And then say “but don’t worry, Covid vaccines were know are safe”.

You’re contradicting yourself.

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