We included twenty-five studies with a total of 1024 participants. Most of these studies were undertaken in the 1970s when penfluridol was launched. Ten studies, with 365 patients, compared penfluridol to placebo. In the meta-analysis of medium-term lasting studies, penfluridol was superior to placebo in the main efficacy measures: 'improvement in global state' (n=159, 4 RCTs, RR 0.69 CI 0.6 to 0.8, NNT 3 CI 2 to 10) and 'needing additional antipsychotic' (n=138, 5 RCTs, RR 0.43 CI 0.2 to 0.8, NNT 3 CI 1.8 to 20).
A total of 449 patients from eleven studies were randomised to penfluridol or oral typical antipsychotics. There were no particular differences between penfluridol versus chlorpromazine, fluphenazine, trifluoperazine, thioridazine, or thiothixene for the main outcome measures in medium-term trials: 'improvement on global state' (N=2 studies), 'leaving the study early' (N=6), 'needing additional antipsychotic' (N=3), needing antiparkinsonian medication (N=2), and side-effects.
Six studies, with 274 patients, compared penfluridol to depot typical antipsychotics. In general, for the efficacy and safety measures, no differences were established, but penfluridol was superior in keeping the patients in treatment; 'leaving the study early' (n=218, 5RCTs, RR 0.55 CI 0.3 to 0.97, NNT 6 CI 3.4 to 50).