B oston-based biotech Karuna Therapeutics (KRTX) said Monday that a novel combination pill achieved the main goal of a mid-stage clinical trial by reducing the acute psychosis and related symptoms experienced by patients with schizophrenia.
KarXT is an oral co-formulation of xanomeline, a muscarinic receptor agonist, and trospium, a muscarinic receptor antagonist, which acts through preferential stimulation of muscarinic receptors in the central nervous system.
The experimental combination antipsychotic drug from Karuna Therapeutics did well in a mid-stage clinical trial, reducing acute psychosis in patients with schizophrenia. It also had a more profound impact on hallucinations and delusions, and on emotional and social withdrawal, than placebo.
Antipsychotic medications have poor patient compliance issues, due largely to the unpleasant side effects they produce.
Karuna’s drug, called KarXT, targets the muscarinic acetylcholine receptors in the brain — a pathway that first was targeted by Eli Lilly in the 1990s. Lilly nixed the drug, called xanomeline, because of the intense nausea, dizziness, and vomiting that patients experienced.
Karuna also uses xanomeline, but it’s in combination with a second drug called tropsium that’s meant to mitigate the difficult side effects.