Can typical and atypical antipsychotics show differential effectiveness in treating paranoia and hallucinations in schizophrenia?

A dopamine excess is thought to be involved in positive psychotic symptoms in schizophrenia. All current antipsychotics show a degree of dopamine receptor antagonism. Little is known about the differential effectiveness of different antipsychotics in treating specific sets of symptoms. We report the case of a 35-year-old man with schizophrenia who presented with prominent hallucinatory symptoms (Positive and Negative Syndrome Scale [PANSS] P1=5, P3=5, P6=5) resistant to high doses of a dopamine, serotonin receptor antagonist, olanzapine. Switching from olanzapine to zuclopenthixol, a dopamine D2 receptor antagonist, led to a complete shift of his symptomatology: his hallucinations abated, however, he presented as very highly paranoid (PANSS P1=6, P3=2, P6=7). On a combination of both antipsychotics, his symptoms subsided (PANSS P1=3, P3=2, P6=2). We discuss the potential for differential effectiveness of different antipsychotic medications in treating hallucinations and paranoia. We argue that future studies could address this question by stratifying patients based on symptoms.

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Striatal Dopamine D2 Receptor Occupancy Induced by Daily Application of Blonanserin Transdermal Patches: Phase II Study in Japanese Patients With Schizophrenia

The International Journal of Neuropsychopharmacology ◽

10.1093/ijnp/pyaa071 ◽

2020 ◽

Author(s):

Hironori Nishibe ◽

Amane Tateno ◽

Takeshi Sakayori ◽

Masahiro Yamamoto ◽

WooChan Kim ◽

...

Keyword(s):

Phase Ii Study ◽

Dopamine D2 Receptor ◽

D2 Receptor ◽

Receptor Occupancy ◽

Striatal Dopamine ◽

Diurnal Variability ◽

Dopamine D2 ◽

Dopamine D2 Receptor Occupancy ◽

Syndrome Scale ◽

Negative Syndrome

Abstract Background Transdermal antipsychotic patch formulations offer potential benefits, including improved adherence. This study investigated the striatal dopamine D2 receptor occupancy with daily blonanserin transdermal patch application. Methods This open-label, phase II study enrolled 18 Japanese outpatients (20 to <65 years) with schizophrenia (DSM-IV-TR criteria; total Positive and Negative Syndrome Scale score <120 at screening) treated with blonanserin 8-mg or 16-mg tablets. Patients continued tablets for 2–4 weeks at their current dose and were then assigned to once-daily blonanserin patches (10/20/40/60/80 mg daily) for 2–4 weeks based on the oral dose. [11C]raclopride positron emission tomography scanning determined blonanserin striatal dopamine D2 receptor occupancy (primary endpoint). Secondary endpoints included assessment of receptor occupancy by dose, changes in Positive and Negative Syndrome Scale and Clinical Global Impressions-Severity of Illness-Severity scores, patient attitudes towards adherence, and patch adhesiveness. Results Of 18 patients who started the blonanserin tablet treatment period, 14 patients completed treatment. Mean D2 receptor occupancy for blonanserin tablets 8 mg/d (59.2%, n = 5) and 16 mg/d (66.3%, n = 9) was within the values for blonanserin patches: 10 mg/d (33.3%, n = 3), 20 mg/d (29.9%, n = 2), 40 mg/d (61.2%, n = 3), 60 mg/d (59.0%, n = 3), and 80 mg/d (69.9%, n = 3). Occupancy generally increased with increasing blonanserin dose for both formulations with the half maximal receptor occupancy for tablets and patches associated with doses of 6.9 mg/d and 31.9 mg/d, respectively. Diurnal variability in occupancy was lower during transdermal patch treatment than during tablet treatment. Blonanserin transdermal patches were well tolerated with no major safety concerns. Conclusions Blonanserin patches (40/80 mg/d) have lower diurnal variability in occupancy than blonanserin tablets (8/16 mg/d), and patches at doses of 40 mg/d and 80 mg/d appear to be a suitable alternative for blonanserin tablets at doses of 8 mg/d and 16 mg/d, respectively. Blonanserin patches represent a potential new treatment option for patients with schizophrenia. Trial registry JAPIC Clinical Trials Information registry (www.clinicaltrials.jp; JapicCTI-No: JapicCTI-121914).

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Multi-Tissue Transcriptomic-Informed In Silico Investigation of Drugs for the Treatment of Dengue Fever Disease

Viruses ◽

10.3390/v13081540 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1540

Author(s):

Beatriz Sierra ◽

Ana Cristina Magalhães ◽

Daniel Soares ◽

Bruno Cavadas ◽

Ana B. Perez ◽

...

Keyword(s):

Receptor Antagonist ◽

Dengue Fever ◽

In Silico ◽

Serotonin Receptor ◽

Neglected Tropical Diseases ◽

Dengue Infection ◽

Severe Dengue ◽

Functional Evaluation ◽

Atpase Inhibitor ◽

Serotonin Receptor Antagonist

Transcriptomics, proteomics and pathogen-host interactomics data are being explored for the in silico–informed selection of drugs, prior to their functional evaluation. The effectiveness of this kind of strategy has been put to the test in the current COVID-19 pandemic, and it has been paying off, leading to a few drugs being rapidly repurposed as treatment against SARS-CoV-2 infection. Several neglected tropical diseases, for which treatment remains unavailable, would benefit from informed in silico investigations of drugs, as performed in this work for Dengue fever disease. We analyzed transcriptomic data in the key tissues of liver, spleen and blood profiles and verified that despite transcriptomic differences due to tissue specialization, the common mechanisms of action, “Adrenergic receptor antagonist”, “ATPase inhibitor”, “NF-kB pathway inhibitor” and “Serotonin receptor antagonist”, were identified as druggable (e.g., oxprenolol, digoxin, auranofin and palonosetron, respectively) to oppose the effects of severe Dengue infection in these tissues. These are good candidates for future functional evaluation and clinical trials.

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