Evaluation of penfluridol in hospitalised chronic schizophrenic

Thirty chronic schizophrenic patients completed 12 week treatment with a single weekly dose of 20 mg penfluridol, a new long acting oral neuroleptic. The patients were evaluated by using modified rating scale. Significant reduction in scores was demonstrated in 15 out of 26 symptom variables. Few side effects were reported which were easily controlled by conventional antiparkinson agents. Laboratory investigations remained within normal limits.

Comparative short-term evaluation of penfluridol and trifluoperazine in chronic schizophrenia

A double blind comparative study was conducted to evaluate the efficacy and safety of penfluridol and trifluoperazine in patients of chronic schizophrenia. Penfluridol was administered once weekly while trifluoperazine was administered twice daily by preparing identical capsules. The data revealed that both the compounds were similarly effective in maintaining control of symptoms of chronic schizophrenia. However, penfluridol has a definite advantage over trifluoperazine since it is administered once a week instead of twice a day.

Study of penfluridol and chlorpromazine in the treatment of chronic schizophrenia

This study presents data on the use of penfluridol, a once-a-week orally administered, antipsychotic agent, in the treatment of chronic schizophrenic patients. Fifty-nine patients participated in the initial dose titration segment during which doses of penfluridol were adjusted weekly until the patients' condition became stabilized. The starting dose did not exceed 60 mg per week, and the maximum weekly dose did not exceed 140 mg. Forty-one of these patients continued on to participate in a double-blind comparison of penfluridol with chlorpromazine. Maximum doses did not exceed 140 mg per dose per week for penfluridol and 7350 mg per week for chlorpromazine in the double-blind segment. Patients were abruptly switched from their previous neuroleptic medication to penfluridol without loss of control. Side effects, mainly extrapyramidal in nature, were readily alleviated with benztropine mesylate. Penfluridol, administered orally once a week, appeared to be well tolerated; it was comparable to daily chlorpromazine in treating and maintaining schizophrenic patients.

Penfluridol: a neuroleptic drug designed for long duration of action

1. Penfluridol is a unique, long-acting, oral neuroleptic belonging to the diphenylbutylpiperidines. The synthesis of penfluridol represented the result of a well-planned scientific search for a highly lipophilic compound structurally related to haloperidol and pimozide. 2. Because of its unusual lipophilicity, penfluridol distributes extensively in fatty tissues following oral administration. This depot effect produces a very slow release of drug from the tissues, and results in a very long duration of activity. 3. Penfluridol is extensively metabolized by oxidative N-dealkylation to afford, as isolated metabolites, the beta-glucuronide conjugate of the diphenylbutyric acid derivative A1 and the unconjugated basic piperidine moiety B1. It is assumed, at this time, that the pharmacological activity is attributable to the parent compound. 4. When administered clinically at oral doses of 20 to 100 mg/week, penfluridol has been found to be an effective antipsychotic agent. This frequency of dosing is consistent with the pharmacokinetic behavior of the drug in man, and does not appear to result in any inappropriate accumulation of the drug in patients. Wide variations in steady-state levels and plasma elimination half-life have been observed in patient populations.

A long term comparative trial of penfluridol and fluphenazine decanoate in schizophrenic outpatients

Penfluridol, a diphenylbutylpiperidene derivative, is a new long acting neuroleptic, administered orally, once weekly. It is marketed in several European countries and has been used successfully in the treatment of various acute psychoses, for severely ill chronic schizophrenic patients, and as maintenance therapy for chronic schizophrenic patients. The present study was designed to compare, in a double-blind fashion, the efficacy of penfluridol and fluphenazine decanoate in the maintenance therapy of schizophrenic outpatients.

Penfluridol: an open phase III study in acute newly admitted hospitalized schizophrenic patients

An open study was carried out in 17 acutely ill, newly admitted, floridly psychotic schizophrenic patients to a city hospital in New York. Penfluridol was given on a daily basis up to doses of 120 mg and patients were rated objectively by means of different psychometric evaluations; vital signs were monitored daily as were side effects. The drug was found to be a rapid acting, well-tolerated, and highly effective antipsychotic agent within the population of patients explored and within the dose range used. It was particularly effective in acutely agitated floridly paranoid schizophrenics; a statistically significant impact was achieved by 7 days and usually within 72 h after initiating treatment. The drug appears unique in that (1) its effects are realized without the untoward and usually troublesome effects of nonspecific sedation attendant upon the use of many other 'neuroleptic' medications, and (2) even within the relatively high doses used it produced no hypotensive effects. It is concluded that this appears to be a unique antipsychotic agent and a potentially important addition to the treatment armamentarium of both acute and chronic schizophrenic individuals.

Penfluridol, a peroral long-acting neuroleptic, for the maintenance treatment of schizophrenic patients who relapse

In a multicenter collaborative study, 28 newly readmitted schizophrenic patients, stabilized for one week on short-acting neuroleptic drugs, had their medication abruptly changed to penfluridol given once a week on an outpatient basis. The average dose required for maintenance was approximately 40 mg weekly. Analysis of BPRS evaluations carried out during the 16-week trial revealed a significant linear trend toward further improvement. Social functioning, as measured by the KAS questionnaire in the outpatient period of the trial, also revealed a significant linear trend toward improvement. Significant worsening was not found with any psychometric evaluation. Side effects, when observed, were neither frequent nor severe. Three laboratory and vital sign values showed significant changes: increase in BUN concentrations, decrease in pulse rate, and increase in body weight. The changes in weight and pulse appeared to be within relatively normal ranges, and the increase in BUN concentrations did not appear to be clinically significant. During the first part of a long-term study, penfluridol received a high degree of patient acceptability and is a welcome addition to the maintenance treatment of schizophrenia.

Penfluridol in the maintenance treatment of schizophrenic patients newly discharged from a brief therapy unit

Penfluridol, a long-acting neuroleptic that can be administered orally once a week, was compared with chlorpromazine in the maintenance treatment of 29 schizophrenic patients newly discharged from a brief therapy unit. The results indicate that penfluridol was of a similar efficacy to chlorpromazine in the treatment of these patients. Penfluridol-treated patients experienced less drowsiness but more extrapyramidal symptoms than those treated with chlorpromazine.

Cumulative effects of penfluridol, a long-acting neuroleptic drug, as assayed by its behavioral actions

Penfluridol, a long-acting neuroleptic drug, was repeatedly given to rats well trained on the discriminated avoidance schedule (intertrial interval, 25 sec; warning duration, 5 sec), and accumulation of the effects were investigated by observing the behavioral changes. When penfluridol was orally given in a dose of 2-8 mg/kg once daily for 10 consecutive days, the suppression of avoidance response was progressively enhanced until the 3rd-4th day. But from the 4th day, the maximum level of suppression was maintained during the later medication. On its withdrawal, the avoidance response was gradually restored, returning to the initial level in 3-4 days. When 8 mg/kg was given at 1-2 weeks after the withdrawal, the same suppression was observed as after the single administration of the same dose. The progressive enhancement of suppression in the early half of the medication period evidently indicated the cumulative effect. The degree of suppression during the plateau showed a linear correlation with the dosage, and was estimated to be about 3,5 times as high as in the corresponding single administration.

[Activity of a new neuroleptic, penfluridol (R-16341) in long-term treatments]

The difficulties of regular drug intake in long term treatments for psychotic patients gave rise to the need of using medicines at the longest possible intervals, facilitating thus adequate control and regularity. Penfluridol is a neuroleptic meeting that requirement: it is necessary only one dose per week. This paper reviews the results of Penfluridol in 26 patients (20 inpatients and 6 outpatients), ages between 17 and 54 with a mean of 36.8, sex feminine, and the following diagnoses: schizophrenia, paranoid: 14, simple: 8, hebephrenic: 3, catatonic: 1. The patients, divided in two groups of 13 each, had one oral dose a week, of between 10 and 100 mg, during 90 days. The first group took only Penfluridol, suppressing any other medicaments. The other group added Penfluridol to the prescriptions already in use. The results, as described in tables I and II, were evaluated according to 36 items. The general evaluation was positive with no negative biases. The side effects were scarce and temporary: insomnia in 7 cases during the first week, and extra-pyramidal symptoms in another 7 cases, that were controlled with antiparkinsonians. The conclusion is that Penfluridol is a valuable contribution to longterm treatments in psychoses.

[Position of the delayed-action neuroleptic penfluridol (Longperidol/Janssen) in psychiatric therapy]

Longoperidol/Janssen, an orally administered neuroleptic with a five- to seven-day duration of effects, was clinically tested in six mental hospitals in the G.D.R. where the agent was administered to subjects of chronic to subacute schizophrenia. It was not possible for fully consistent results to be obtained in these tests. Workers at mental hospitals in Leipzig and Mühlhausen recommended that the drug should be imported, whereas those at the four other centers (Dresden, Halle, Jena, and Schwerin) did not consider the medication to be indispensable, although they were also able to observe the good effects of the agent.

Controlled trial of penfluridol and thiothixene in the maintenance treatment of chronic schizophrenic syndromes

In a controlled trial of penfluridol and thiothixene as maintenance drugs in patients with chronic schizophrenic syndromes, some improvement over previous neuroleptics was seen with both drugs. This improvement was mainly evident in variables concerned with participation in social activities as assessed with the S-scale and by ward behaviour. The drug dosages necessary were very low and gave few and easily manageable side-effects. There was no significant difference between penfluridol and thiothixene. Penfluridol has the clear practical advantage of being the only long-acting drug for oral administration so far available.

Penfluridol steady-state kinetics in psychiatric patients

Twenty-two hospitalized schizophrenic patients, participating in a large-scale phase II double-blind dose-effect study (30, 60, and 120 mg weekly) of penfluridol, a new diphenylbutylpiperidine neuroleptic, were maintained on a regular dosage regimen for 13 wk. Several blood samples were taken during the last dosage interval. Results show that the peak concentration develops within 12 hr after the last dose. A rapid decline, probably due to tissue re-equilibration, then occurs and is followed by a much slower falloff. Detectable concentrations 168 hr after administration are consistent with the long duration of action of penfluridol. Statistically significant differences between doses were found in the analysis of variance of plasma concentrations at all sampling times and in mean steady-state plasm concentrations. Wide differences in plasma concentrations were noted in patients receiving the same absolute dose, but a good relationship was defined between mean steady-state concentration and the dose expressed as mg per either kg of body weight or square meter of body surface area.

Peroral and parenteral administration of long-acting neuroleptics: a double-blind study of penfluridol compared to flupenthixol decanoate in the treatment of schizophrenia

Fifty-six out of 60 schizophrenic patients completed a double-blind study of two long-acting neuroleptics, penfluridol (peroral) and flupenthixol decanoate (parenteral). Half of the patients were on maintenance therapy of flupenthixol prior to the study, the other half on penfluridol. The actual double-blind study (12 weeks) was commenced after a preliminary period of 4 weeks, the patients in the two main groups being randomly divided into two further groups, one continuing the medication unchanged, the other changing to the alternative drug. It was found possible to make a sudden switch from penfluridol to flupenthixol decanoate and vice versa without any significant change in the condition of the patient. The same dosage (in 70% of the patients from 40 to 80 mg) of penfluridol was used per week as was employed for flupenthixol decanoate per fortnight. Changes in the intensity of the symptoms (total Brief Psychiatric Rating Scale (BPRS) score) were moe pronounced in the preliminary period (during unchanged treatment) than on changed medication in the blind period. Both drugs induced approximately the same degree of akathisia, Parkinsonism and autonomic side effects. The practical consequences of equipotent therapeutical effect of a peroral and parenteral long-acting neuroleptic are briefly discussed.

Gas-liquid chromatographic determination of penfluridol in plasma. A new specific technique

Penfluridol is a new long-acting neuroleptic drug, first shown by Janssen et al. (1970) and later proved by numerous clinical investigations. The plasma level data are in agreement with these findings since penfluridol is measurable in plasma of the patients 7 days after the oral dose of 120 mg/week. In summary, we have provided for the first time a rapid, accurate and precise gas-chromatographic method for measurement of penfluridol in the plasma of schizophrenic patients.