after joining the study, a series of baseline assessments are performed. these include a medical history review, a physical examination, and questionnaires that record current symptoms of schizophrenia or autism spectrum disorder and related irritability.

the purpose of these assessments is to create a reference point for later comparison during the study.

based on the assigned group, you will receive either karxt alone (for schizophrenia) or the combination of karxt plus karx-ec (for irritability associated with autism).

each dose consists of a capsule containing 9999 mg of the active ingredients. the capsule is taken by mouth (oral) as directed by the study team.

the study medication is taken each day, usually at the same time, with a glass of water.

it is important to follow the dosing instructions exactly and not miss any doses unless instructed otherwise.

throughout the treatment period you will attend scheduled clinic visits. during each visit vital signs, laboratory tests, and physical examinations are performed to monitor your health.

you will also complete brief questionnaires, such as the columbia suicide severity rating scale (c-ssrs), which asks about thoughts of self‑harm, and other rating scales that assess movement‑related side effects.

any unwanted medical occurrence, whether it is thought to be related to the study drug or not, should be reported to the study staff. these are called treatment‑emergent adverse events.

serious problems, called serious adverse events, and events of special interest are also recorded and evaluated.

the medication is continued for the entire duration of the study, which may extend for several years until the study end date of 2030‑03‑08, unless you or the study team decide to stop earlier.

after the last dose of study medication, a final safety follow‑up visit is scheduled. this visit includes the same assessments as earlier visits to ensure that any lingering effects are identified and managed.