Analysis of the Finnish cases revealed that all the agranulocytosis cases had occurred within the first 18 weeks of treatment and the authors proposed blood monitoring during this period. The rate of agranulocytosis in Finland appeared to be 20 times higher than in the rest of the world and there was speculation that this may have been due a unique genetic diversity in the region. Whilst the drug continued to be manufactured by Sandoz, and remained available in Europe, development in the U.S. halted. Interest in clozapine continued in an investigational capacity in the United States because, even in the 1980s, the duration of hospitalisation, especially in State Hospitals for those with treatment resistant schizophrenia might often be measured in years rather than days. The role of clozapine in treatment resistant schizophrenia was established by the landmark Clozaril Collaborative Study Group Study #30 in which clozapine showed marked benefits compared to chlorpromazine in a group of patients with protracted psychosis and who had already shown an inadequate response to other antipsychotics. This involved both stringent blood monitoring and a double-blind design with the power to demonstrate superiority over standard antipsychotic treatment. The inclusion criteria were patients who had failed to respond to at least three previous antipsychotics and had then not responded to a single blind treatment with haloperidol (mean dose 61 mg +/- 14 mg/d). Two hundred and sixty-eight were randomised were to double blind trials of clozapine (up to 900 mg/d)  or chlorpromazine (up to 1800 mg/d).
In the television series Last Man On Earth (2015) the character Melissa has a psychotic episode and returns home and starts acting how she did pre-pandemic. Her boyfriend Todd sees her take a medication in the morning and asks her what it is. All she will say is "Santas Penis". Todd searches medication books and finds clozapine = Clause a peen. References
Further reading
External links
"Clozapine". Drug Information Portal. U.S. National Library of Medicine. "Clozapine Risk Evaluation and Mitigation Strategy (REMS) requirements will change on November 15, 2021". U.S. Food and Drug Administration (FDA). 29 July 2021. "Clozapine REMS Modification Frequently Asked Questions". U.S. Food and Drug Administration (FDA). 29 July 2021.