Innovative palliative approaches for terminal respiratory diseases: Exploring the effectiveness and pharmacokinetics of the blonanserin transdermal patch.

BACKGROUND: The blonanserin transdermal patch, the first antipsychotic patch approved in Japan for schizophrenia, was reported to reduce the prevalence of terminal delirium from 70.4 % to 16.3 % and manage refractory dyspnea in respiratory disease (Respir Invest 2023; 240-6). While parkinsonism and akathisia have been reported as adverse events in over 10 % of patients with schizophrenia, such side effects were rare in our terminally ill patient population. To further investigate its effectiveness in this patient population, we conducted a retrospective study with the additional aim of evaluating its pharmacokinetic profile.

METHODS: We retrospectively reviewed the medical records of 150 terminally ill patients with respiratory diseases receiving home medical care and treated with the blonanserin transdermal patch. Plasma blonanserin levels were measured in 32 patients and compared with reconstructed clinical trial data using a normal distribution model.

RESULTS: Twenty-eight patients (18.7 %) developed terminal delirium, which is consistent with our previous study findings. The treatment-emergent adverse events included extrapyramidal symptoms (5.3 %) and skin-related reactions (2.0 %). In previous clinical trials, plasma concentrations on days 7-8 following administration of the 40-mg blonanserin patch were reported as 0.70 ± 0.31 ng/mL, whereas in our study, the corresponding value was markedly lower at 0.29 ± 0.29 ng/mL. Additionally, statistical analysis confirmed that plasma concentrations in our population were significantly lower than those reported in clinical trial data (p = 0.022).

CONCLUSION: The blonanserin transdermal patch demonstrated therapeutic effectiveness and a favorable safety profile in terminally ill patients with respiratory diseases, despite reduced plasma concentrations.