DSP-5423P (DSP) is a transdermal delivery formulation containing 20 mg of blonanserin per 40 cm2 patch. This open-label, single-arm study was conducted to evaluate the safety and tolerability of repeated application of DSP for 2 weeks in 8 patients with schizophrenia. Four patches of DSP per day (80 mg/day of blonanserin), possessing nearly equivalent striatum dopamine D2 receptor occupancy to oral administration of 16 mg/day of blonanserin, were applied to the upper back of the patient once per day for 2 weeks. Adverse events (AEs) and pharmacokinetics and schizophrenia rating scales (PANSS and CGI-S) were used to evaluate safety. AEs were reported in 7 out of 8 cases, with application site erythema (n＝5) the most common, followed by application site pruritus (n＝3), and akathisia (n＝3). No serious AEs occurred, and all AEs were determined to be mild in severity. Extrapyramidal AEs were reported in 4 cases, including akathisia (n＝3), bradykinesia (n＝2), and tremor (n＝1). Adverse drug reactions related to the application site occurred in 5 cases; however, all patients recovered with or without treatment with topical agents and completed the study. No apparent change was found in the Drug Induced Extra-Pyramidal Symptoms Scale total score during the study. Regarding pharmacokinetics, plasma concentration of blonanserin and its metabolites did not show any significant changes after application of DSP. Changes in PANSS and CGI-S scores revealed no worsening of schizophrenia during the study. This study demonstrated that there were no safety or tolerability issues with 2 weeks' administration of DSP. (Trial No. JapicCTI-142423)
