This clinical trial is focused on studying the effects of a medication called NaBen on adults with refractory schizophrenia. Schizophrenia is a mental health condition that affects how a person thinks, feels, and behaves. Refractory schizophrenia refers to cases where symptoms do not improve significantly with standard treatments. The study will test NaBen, which is a type of medication known as a D-amino acid oxidase inhibitor, to see if it can help improve symptoms when used alongside another medication called clozapine.
The purpose of the study is to evaluate the safety and effectiveness of NaBen in reducing the symptoms of schizophrenia that persist despite treatment with clozapine. Participants in the study will receive either NaBen or a placebo, which looks like the medication but does not contain the active ingredient. The study will be conducted in two parts. In the first part, different doses of NaBen will be tested to find the most effective dose. In the second part, the best dose from the first part will be used to further assess its effectiveness compared to the placebo.
Participants will take the medication orally in the form of film-coated tablets for a period of up to eight weeks. Throughout the study, changes in symptoms will be monitored using various scales and assessments to determine the impact of the treatment. The goal is to find out if NaBen can provide additional benefits for those who have not responded well to other treatments for schizophrenia.



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