Pfizer Inc said yesterday that the US
Food and Drug Administration (FDA) has approved ziprasidone HCl capsules, a
novel antipsychotic medicine for treatment of schizophrenia.
Discovered and developed by Pfizer, ziprasidone is a serotonin and
dopamine antagonist that is effective across its dose range in treating the
positive and negative symptoms associated with schizophrenia. These include
visual and auditory hallucinations, delusions, lack of motivation and social
withdrawal. The 4,500-patient worldwide clinical trials program for
ziprasidone is the largest ever conducted for an antipsychotic medicine prior
Despite advances in treatment, physicians and other health care providers
continue to face significant challenges in the management of schizophrenia,
"Schizophrenia is a devastating and debilitating psychiatric disorder,
impacting patients, their family members and caregivers," said John F.
Niblack, Ph.D. Vice Chairman and President of Pfizer Global Research and
Development. "Ziprasidone is an important new therapeutic option with
long-term efficacy and a very favorable side effect profile, including an
essentially neutral effect on patients' weight levels."
Weight gain, associated with some widely used antipsychotic medicines, is
distressing and stigmatizing to patients, and can result in patient
non-compliance. Patients who gain weight may also be at greater risk for
cardiovascular complications such as increased lipid levels and poor glycemic
control. Hence, the weight neutral profile of ziprasidone should prove an
important and advantageous feature of the drug.
Schizophrenia is a life-long illness that affects approximately one
percent of the world's population and is estimated to cost more than
$104 billion in hospital costs, medications, health care services and lost
productivity. Typically, schizophrenia strikes men and women in their late
adolescence or early 20s and is chronic, often with multiple relapses and
impaired daily functioning.
In placebo-controlled, short-term (4 and 6 week) clinical trials,
ziprasidone 20 to 100 mg twice daily was statistically superior to placebo for
treatment of positive and negative symptoms in patients with acute
exacerbation of schizophrenia and schizoaffective disorder.
In a one-year placebo-controlled study, in chronic, stable inpatients,
ziprasidone was shown to be effective in delaying the time to and rate of
relapse. Since schizophrenia is typically a lifelong illness that is
complicated by high rates of relapse, relapse prevention is an important goal
in the management of this illness.
The most common side effects exhibited by persons in clinical trials
treated with ziprasidone included headache, somnolence, abnormal movements,
respiratory disorders, nausea, constipation and dyspepsia. These side effects
were generally of mild to moderate severity and rarely led to discontinuation
of the drug.
Ziprasidone is also associated with a small prolongation of the QTc
interval of the electrocardiogram, an effect seen with certain other marketed
medicines, including some anti-psychotics. This effect was well characterized
in the extensive ziprasidone clinical trials database and is reflected in the
FDA's product labeling, which suggests that physicians use their best
judgement, based on the overall status of the patient, as to whether
ziprasidone or another antipsychotic agent be used first.
Pfizer said the product label does not include a black box warning or a
requirement that patients receive electrocardiograms either at initiation or
during treatment with ziprasidone.
The company said it expects to introduce ziprasidone in the US in 20 mg,
40 mg, 60 mg and 80 mg capsules in March. Pfizer said it is discussing
several potential trade names for ziprasidone with the FDA.