Karxt efficacy compared to current drugs

I found a good website I believe is originally written in Japanese. There’s an article on how Karxt compares to other drugs in positive and negative symptoms using the PANSS effect size. For negative symptoms it’s second only to clozapine.


Doesn’t clozapine not do so well with negative symptoms though even though I guess it’s effacious for the totality of symptoms? I think there’s a lot of unanswered questions about KARxt, it seems like a highly complex drug. Some people have compared it to a Ritalin type drug for schizophrenics, I think it’s more complicated than that. I believe it’s going to have incredible antidepressant properties and connect the gut and brain for communication. Dunno though

The link displays Phase 2 result.
The results reported in August 2022 Phase 3 trial were a little different: “The trial met its primary endpoint, with KarXT demonstrating a statistically significant and clinically meaningful 9.6-point reduction in the Positive and Negative Syndrome Scale (PANSS) total score compared to placebo (-21.2 KarXT vs. -11.6 placebo, p<0.0001) at Week 5 (Cohen’s d effect size of 0.61).”

It would seem that there is a difference in anecdotal and statistical evidence for drugs. I want to enter into a Karxt study now but I’m just worried it won’t work for positive symptoms and I’ll have a relapse.

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That effect size (.61) would be significantly lower than the phase 2 value of .75, right?

Yes I think first phase 3 effect of .61 was lower but good. There are other phase 3 trials running, so they should have more results in several months. Some trials are for add on. Phase 3 trials:https://clinicaltrials.gov/ct2/results?recrs=ab&cond=&term=karxt&cntry=&state=&city=&dist=

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Thank you for the link to my blog.

Indeed, in Phase 3, the effect size of KarXT was 0.61. I think this is because the placebo improvement was much greater than in Phase 2.

However, it was still more effective than risperidone (0.55) and olanzapine (0.56).

In addition, KarXT has fewer extrapyramidal symptoms and less weight gain than those drugs, so I think it is a pretty good drug so far.

I will be preparing an article on Phase 3 of KarXT later this month, so please watch for it.


Welcome to the forum, Mats. (They may not let you link the first few times you post. Many forums do not at first.)
Yes the effect size changes with placebo result.
I look forward to your posts.

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