Clozapine Neutropenia Risk Results in FDA Warning Update

Amid concerns about the potential side effects of clozapine, federal health officials are requiring new warnings and patient monitoring for the schizophrenia medicine, indicating that there is growing evidence that users may face an increased risk of a severe blood condition, known as neutropenia.

In a drug safety communication issued September 15, the FDA announced changes to the requirements for monitoring, prescribing, dispensing, and receiving of the schizophrenia medicine clozapine, which is available generically and sold under the brand names Clozaril and FazaClo.

Clozapine is an antipsychotic medication used to treat patients diagnosed with severe schizophrenia whose symptoms cannot be controlled by standard antipsychotic treatment or therapies. The medication has also been used to treat reoccurring suicidal behavior in patients with schizophrenia or schizoaffective disorder. The drug is used to block various receptors in the brain and restore balance in patient’s dopamine and serotonin level.

The new clozapine warnings come amid a growing trend of patients experiencing severe neutropenia, a serious blood condition that causes dangerously low white blood cell counts. As a result of the low white blood cell count, patients are very susceptible to infections. The condition is extremely harmful and can be life threatening, especially in the elderly and those with weakened immune systems.

Due to the clozapine neutropenia side effects, the FDA is requiring clarified and enhanced prescribing information that explains how to monitor patients for the blood condition and how to manage patients treatments. Secondly, the FDA has passed a new shared risk evaluation and mitigation strategy (REMS), called the Clozapine REMS Program, which is expected to reduce the burden and possible confusion related to having separate registries for individual clozapine medicines.

The new requirements will mandate prescribing doctors to perform an absolute neutrophil count (ANC) that will continuously be performed and evaluated to ensure the patient’s white blood cells do not reach dangerous levels. The REMS Program requires that for outpatients the ANC test results be reported before the Clozapine prescription is dispensed and for inpatients the ANC test results must be reported within 7 days of the most recent blood sample. Additional provisions will require all prescribers and pharmacies to be certified in the Clozapine REMS Program following a specific transition starting on October 12, 2015.