The ZEISIG study (Ziprasidone Experience in Schizophrenia in Germany/Austria) investigated the effectiveness of ziprasidone as measured by discontinuation rates and mean changes of the BPRS total. Secondary objectives included quality of life, subjective well-being, tolerability, and safety.

Two hundred and seventy-six subjects with schizophrenia and schizoaffective disorder were treated within an open-label, 12-week, prospective, flexible-dose observational trial of ziprasidone (40-160mg/day). Baseline and outcome assessments mainly included Brief Psychiatric Rating Scale (BPRS), Clinical Global Impressions Scale (CGI), Short-Form 12 (SF-12), and Subjective Well-being under Neuroleptic treatment (SWN-K).

Study discontinuation due to any cause was evident in 58% of subjects, most of them within the first 4weeks after study initiation. In study completers, ziprasidone was associated with improvements in BPRS total (44.8 to 33.6; p<0.001), CGI, SF-12, and SWN-K total scores (80.5 to 89.5). Ziprasidone was related to reduction of weight, fasting glucose, and serum lipids. No cardiovascular adverse event or significant increase of the QTc interval was observed.

Approximately 60% of subjects discontinued ziprasidone prematurely, probably related to an initial and overall underdose. The present study confirmed previous tolerability and safety data of ziprasidone as well as results of its effectiveness. Independent from reason to switch, previous antipsychotic class, and severity of illness at baseline, the recommended starting dose of 80mg/day as well as the maximum treatment dose of 160mg/day may not be sufficient for a selected subgroup of patients.