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  1. Postmarket Drug Safety Information for Patients and Providers

Information on Clozapine

Latest Update

On November 19, 2021, FDA temporarily suspended certain Clozapine REMS program requirements to ensure continuity of care for patients taking clozapine. For more information, please see the updated CDER Statement.

Information on Clozapine

Clozapine (marketed as Clozaril, Fazaclo ODT, Versacloz and generics) is an antipsychotic medicine used to treat schizophrenia in patients whose symptoms are not controlled with standard antipsychotic drugs. Clozapine is also used in patients with recurrent suicidal behavior associated with schizophrenia or schizoaffective disorder.

While clozapine is beneficial for some patients, there are risks associated with this drug. Specifically, clozapine can decrease the number of neutrophils, a type of white blood cell, that function in the body to fight off infections. When neutrophils are significantly decreased, severe neutropenia may result and the body may become prone to infections. For this reason, patients taking clozapine need to have their absolute neutrophil count (ANC) monitored on a regular basis. This monitoring requirement serves as the basis for the Clozapine Risk Evaluation and Mitigation Strategy (REMS).

Clozapine REMS Program

The Clozapine REMS Programwas approved in September 2015 and is a “shared-system” program, meaning that it includes all clozapine medicines approved by the Food and Drug Administration (FDA). The Clozapine REMS Program ensures optimal patient monitoring for and management of clozapine-induced severe neutropenia, providing a centralized system for prescribers and pharmacists in managing patient risk, regardless of which clozapine product is being used. Prior to the approval of the Clozapine REMS Program, individual clozapine manufacturers operated separate patient registries.

In response to implementation challenges identified following the approval of the Clozapine REMS Program, the FDA announced, in November 2015, that the deadlines for certification of prescribers and pharmacies would be extended to help ensure that health care professionals had sufficient time to complete certification and to ensure patient access to clozapine was maintained.

We believe that most of the issues identified to date have been resolved. If prescribers and pharmacies experience problems while attempting to become certified, they should contact the Clozapine REMS Call Center at 844-267-8678.

In an effort to provide timely clozapine information to prescribers, pharmacies, patients, and distributors, the FDA will post any related updates on clozapine and the Clozapine REMS Program on this page.

Related Resources

If you have questions or concerns about the Clozapine REMS Program or its website please contact FDA at [email protected], 1-855-543-3784 or 301-796-3400.

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