Efficacy and safety of World Health Organization group 5 drugs for multidrug-resistant tuberculosis treatment.

The efficacy and toxicity of several drugs now used to treat multidrug-resistant tuberculosis (MDR-TB) have not been fully evaluated. We searched three databases for studies assessing efficacy in MDR-TB or safety during prolonged treatment of any mycobacterial infections, of drugs classified by the World Health Organization as having uncertain efficacy for MDR-TB (group 5). We included 83 out of 4002 studies identified. Evidence was inadequate for meropenem, imipenem and terizidone. For MDR-TB treatment, clarithromycin had no efficacy in two studies (risk difference (RD) -0.13, 95% CI -0.40-0.14) and amoxicillin-clavulanate had no efficacy in two other studies (RD 0.07, 95% CI -0.21-0.35). The largest number of studies described prolonged use for treatment of non-tuberculous mycobacteria. Azithromycin was not associated with excess serious adverse events (SAEs). Clarithromycin was not associated with excess SAEs in eight controlled trials in HIV-infected patients (RD 0.00, 95% CI -0.02-0.02), nor in six uncontrolled studies in HIV-uninfected patients, whereas six uncontrolled studies in HIV-infected patients clarithromycin caused substantial SAEs (proportion 0.20, 95% CI 0.12-0.27). For most group 5 drugs we found inadequate evidence of safety for prolonged use or for efficacy for MDR-TB, although macrolides appeared to be safe in prolonged use.

Reduced emergence of isoniazid resistance with concurrent use of thioridazine against acute murine tuberculosis.

The repurposing of existing drugs is being pursued as a means by which to accelerate the development of novel regimens for the treatment of drug-susceptible and drug-resistant tuberculosis (TB). In the current study, we assessed the activity of the antipsychotic drug thioridazine (TRZ) in combination with the standard regimen in a well-validated murine TB model. Single-dose and steady-state pharmacokinetic studies were performed in BALB/c mice to establish human-equivalent doses of TRZ. To determine the bactericidal activity of TRZ against TB in BALB/c mice, three separate studies were performed, including a dose-ranging study of TRZ monotherapy and efficacy studies of human-equivalent doses of TRZ with and without isoniazid (INH) or rifampin (RIF). Therapeutic efficacy was assessed by the change in mycobacterial load in the lung. The human-equivalent dose of thioridazine was determined to be 25 mg/kg of body weight, which was well tolerated in mice. TRZ was found to accumulate at high concentrations in lung tissue relative to serum levels. We observed modest synergy during coadministration of TRZ with INH, and the addition of TRZ reduced the emergence of INH-resistant mutants in mouse lungs. In conclusion, this study further illustrates the opportunity to reevaluate the contribution of TRZ to the sterilizing activity of combination regimens to prevent the emergence of drug-resistant M. tuberculosis.

Thioridazine lacks bactericidal activity in an animal model of extracellular tuberculosis.

OBJECTIVES: The antipsychotic drug thioridazine is active in the murine model of tuberculosis infection, which is predominantly intracellular in nature. Recent clinical reports suggest that thioridazine may play a role in the treatment of drug-resistant tuberculosis. We studied the tuberculocidal activity of thioridazine in guinea pigs, which develop necrotic lung granulomas histologically resembling their human counterparts. METHODS: Pharmacokinetic studies were performed in guinea pigs to establish human-equivalent doses of thioridazine. Guinea pigs were aerosol-infected with ∼100 bacilli of Mycobacterium tuberculosis and single-drug treatment was started 4 weeks later with a range of thioridazine doses daily (5 days/week) for up to 4 weeks. Control animals received no treatment or 60 mg/kg isoniazid. RESULTS: The human-equivalent dose of thioridazine was determined to be 5 mg/kg with saturable absorption noted above 50 mg/kg. At the start of treatment, the lung bacterial burden was ∼6.2 log10 cfu. Although isoniazid reduced bacillary counts more than 10-fold, thioridazine monotherapy showed limited killing over the range of doses tested, reducing lung bacillary counts by 0.3-0.5 log10 following 1 month of treatment. Thioridazine was tolerated up to 40 mg/kg. CONCLUSIONS: Thioridazine has limited bactericidal activity against extracellular bacilli within necrotic granulomas. Its contribution to the sterilizing activity of combination regimens against drug-susceptible and drug-resistant tuberculosis remains to be determined.

Successful alternative treatment of extensively drug-resistant tuberculosis in Argentina with a combination of linezolid, moxifloxacin and thioridazine.

OBJECTIVES: Current drug choices to treat extensively drug-resistant (XDR) tuberculosis (TB) are scarce; therefore, information on the safety, tolerability and efficacy of alternative regimens is of utmost importance. The aim of this study was to describe the management, drug adverse effects and outcome of alternative combined treatment in a series of XDR-TB patients. PATIENTS AND METHODS: A retrospective study was performed on 17 non-AIDS, pulmonary adult patients with XDR-TB admitted to a referral treatment centre for infectious diseases in Buenos Aires from 2002 through 2008. Drug susceptibility testing was performed under regular proficiency testing and confirmed at the national TB reference laboratory. RESULTS: Linezolid was included in the drug regimens of all patients; moxifloxacin and/or thioridazine were included in the regimens of 14 patients. Clinically tractable drug adverse effects were observed in nine patients, the most frequent being haematological disorders and neurotoxicity. In two patients, thioridazine was discontinued. Negative culture conversion was achieved in 15 patients, 11 completed treatment meeting cure criteria, 4 are still on follow-up with good evolution, 1 defaulted treatment and 1 was lost to follow-up. CONCLUSIONS: The combination of linezolid, moxifloxacin and thioridazine is recommended for compassionate use in specialized centres with expertise in the management of XDR-TB.

Outcome of patients after market withdrawal of thioridazine: a retrospective analysis in a nationwide cohort.

OBJECTIVE: Thioridazine is a first-generation antipsychotic drug that was withdrawn from the market worldwide in 2005. The outcome of clinically stable schizophrenia patients who used thioridazine before market withdrawal was evaluated. METHODS: Nationwide registers in Finland were utilized to study thioridazine use, hospitalization rate and length of hospital stay. RESULTS: Although thioridazine use continued to diminish year after year, the hospitalization rate remained constant until the withdrawal year of 2005, when the percentage of patients hospitalized for schizophrenia doubled. CONCLUSION: The market withdrawal of thioridazine predisposed many stable patients towards psychotic relapses. In order to minimize this kind of risk, an overall risk-benefit assessment and a clear-cut plan for the replacement of an antipsychotic should be established before market withdrawal.

Nonclinical cardiovascular safety assessment of thioridazine: Impact of autonomic tone, body temperature, and choice of species.

Pending updates to ICH S7B/E14 guidelines will enable the substitution of human TQT studies with support from concomitant negative hERG and non-rodent CV studies. This retrospective analysis compared the effects of thioridazine (THD) (5-20 mg/kg) on heart rate (HR), blood pressure (BP), body temperature (Tc), and QT in the dog (n = 6), cynomolgus monkey (n = 4), and Goettingen minipig (n = 4) with data from previously completed studies employing crossover designs. As QT measurements are confounded by HR and Tc changes, QT effects were individually corrected for changes in HR (QTca) and Tc (QTcaT). THD-induced hemodynamic changes seen in humans were most accurately reflected in the monkey and, to a lesser extent, the dog, but not in the minipig. The minipig was most sensitive to THD QTc effects. When QTca was adjusted for THD-associated Tc decreases in minipigs and monkeys, the minipig revealed a lessened but pronounced QTcaT increase (48 ms). In the monkey, a persistent QTca increase was reduced to only a transient (0.5-3 h) QTcaT increase (20 ms). The dog's lack of THD QTca effects triggered co-administration of atenolol (AT) to attenuate THD-induced HR increases in the dog and monkey. THD + AT revealed peak QTcaT increases of 32 ms in the dog and 40 ms in the monkey, suggesting potential autonomic nervous system (ANS) interference in detecting repolarization changes. These results highlight critical species-specific differences in the outcome of parallel safety investigations. Species selection for nonclinical safety studies should consider the potential impact of Tc and ANS effects to avoid false-negative or overly positive outcomes.

A phase 1 trial evaluating thioridazine in combination with cytarabine in patients with acute myeloid leukemia.

We completed a phase 1 dose-escalation trial to evaluate the safety of a dopamine receptor D2 (DRD2) antagonist thioridazine (TDZ), in combination with cytarabine. Thirteen patients 55 years and older with relapsed or refractory acute myeloid leukemia (AML) were enrolled. Oral TDZ was administered at 3 dose levels: 25 mg (n = 6), 50 mg (n = 4), or 100 mg (n = 3) every 6 hours for 21 days. Intermediate-dose cytarabine was administered on days 6 to 10. Dose-limiting toxicities (DLTs) included grade 3 QTc interval prolongation in 1 patient at 25 mg TDZ and neurological events in 2 patients at 100 mg TDZ (gait disturbance, depressed consciousness, and dizziness). At the 50-mg TDZ dose, the sum of circulating DRD2 antagonist levels approached a concentration of 10 µM, a level noted to be selectively active against human AML in vitro. Eleven of 13 patients completed a 5-day lead-in with TDZ, of which 6 received TDZ with hydroxyurea and 5 received TDZ alone. During this period, 8 patients demonstrated a 19% to 55% reduction in blast levels, whereas 3 patients displayed progressive disease. The extent of blast reduction during this 5-day interval was associated with the expression of the putative TDZ target receptor DRD2 on leukemic cells. These preliminary results suggest that DRD2 represents a potential therapeutic target for AML disease. Future studies are required to corroborate these observations, including the use of modified DRD2 antagonists with improved tolerability in AML patients. This trial was registered at www.clinicaltrials.gov as #NCT02096289.

Thioridazine for schizophrenia.

BACKGROUND: Thioridazine is an antipsychotic that can still be used for schizophrenia although it is associated with the cardiac arrhythmia, torsades de pointe. OBJECTIVES: To review the effects of thioridazine for people with schizophrenia. SEARCH STRATEGY: For this 2006 update, we searched the Cochrane Schizophrenia Group's Register (June 2006). SELECTION CRITERIA: We included all randomised clinical trials comparing thioridazine with other treatments for people with schizophrenia or other psychoses. DATA COLLECTION AND ANALYSIS: We reliably selected, quality rated and extracted data from relevant studies. For dichotomous data, we estimated relative risks (RR), with the 95% confidence intervals (CI). Where possible, we calculated the number needed to treat/harm statistic (NNT/H) on an intention-to-treat basis. MAIN RESULTS: This review currently includes 42 RCTs with 3498 participants. When thioridazine was compared with placebo (total n=668, 14 RCTs) we found global state outcomes favoured thioridazine (n=105, 3 RCTs, RR 'no change or worse' by 6 months 0.33 CI 0.2 to 0.5, NNT of 2 CI 2 to 3). Thioridazine is sedating (n=324, 3 RCTs, RR 5.37 CI 3.2 to 9.1, NNH 4 CI 2 to 74). Generally, thioridazine did not cause more movement disorders than placebo.Twenty-seven studies (total n=2598) compared thioridazine with typical antipsychotics. We found no significant difference in global state (n=743, 11 RCTs, RR no short-term change or worse 0.98 CI 0.8 to 1.2) and medium-term assessments (n=142, 3 RCTs, RR 0.99, CI 0.6 to 1.6). We found no significant differences in the number of people leaving the study early 'for any reason' (short-term, n=1587, 19 RCTs, RR 1.07 CI 0.9 to 1.3). Extrapyramidal adverse events lower for those allocated to thioridazine (n=1082, 7 RCTs, RR use of antiparkinsonian drugs 0.45 CI 0.4 to 0.6). Thioridazine did seem associated with cardiac adverse effects (n=74, 1 RCT, RR 'any cardiovascular adverse event' 3.17 CI 1.4 to 7.0, NNH 3 CI 2 to 5). Electrocardiogram changes were significantly more frequent in the thioridazine group (n=254, 2 RCTs, RR 2.38, CI 1.6 to 3.6, NNH 4 CI 3 to 10). Six RCTs (total n=344) randomised thioridazine against atypical antipsychotics. Global state rating did not reveal any short-term difference between thioridazine and remoxipride and sulpiride (n=203, RR not improved or worse 1.00 CI 0.8 to 1.3). Limited data did not highlight differences in adverse event profiles. AUTHORS' CONCLUSIONS: Although there are shortcomings, there appears to be enough consistency over different outcomes and periods to confirm that thioridazine is an antipsychotic of similar efficacy to other commonly used antipsychotics for people with schizophrenia. Its adverse events profile is similar to that of other drugs, but it may have a lower level of extrapyramidal problems and higher level of ECG changes. We would advocate the use of alternative drugs, but if its use in unavoidable, cardiac monitoring is justified.

An incorrect diagnosis of psychosis?

This article examines a recent claim in which a patient alleged his general practitioner had incorrectly diagnosed him as suffering from psychosis. The GP had prescribed Melleril, which was complicated by the development of pancytopaenia.

Systemic thioridazine in combination with dicloxacillin against early aortic graft infections caused by Staphylococcus aureus in a porcine model: In vivo results do not reproduce the in vitro synergistic activity.

INTRODUCTION: Conservative treatment solutions against aortic prosthetic vascular graft infection (APVGI) for inoperable patients are limited. The combination of antibiotics with antibacterial helper compounds, such as the neuroleptic drug thioridazine (TDZ), should be explored. AIM: To investigate the efficacy of conservative systemic treatment with dicloxacillin (DCX) in combination with TDZ (DCX+TDZ), compared to DCX alone, against early APVGI caused by methicillin-sensitive Staphylococcus aureus (MSSA) in a porcine model. METHODS: The synergism of DCX+TDZ against MSSA was initially assessed in vitro by viability assay. Thereafter, thirty-two pigs had polyester grafts implanted in the infrarenal aorta, followed by inoculation with 106 CFU of MSSA, and were randomly administered oral systemic treatment with either 1) DCX or 2) DCX+TDZ. Treatment was initiated one week postoperatively and continued for a further 21 days. Weight, temperature, and blood samples were collected at predefined intervals. By termination, bacterial quantities from the graft surface, graft material, and perigraft tissue were obtained. RESULTS: Despite in vitro synergism, the porcine experiment revealed no statistical differences for bacteriological endpoints between the two treatment groups, and none of the treatments eradicated the APVGI. Accordingly, the mixed model analyses of weight, temperature, and blood samples revealed no statistical differences. CONCLUSION: Conservative systemic treatment with DCX+TDZ did not reproduce in vitro results against APVGI caused by MSSA in this porcine model. However, unexpected severe adverse effects related to the planned dose of TDZ required a considerable reduction to the administered dose of TDZ, which may have compromised the results.

Thioridazine induces immediate and delayed erythema in photopatch test.

Thioridazine is a phenothiazine derivative that has been used as an antipsychotic; it rarely causes photosensitization. However, we noticed that this drug induced an erythematous reaction in a photopatch test. Six volunteers were patch tested with various concentrations of thioridazine and irradiated with a range of UVA doses, and the time courses of the color of and blood flow to the test sites were monitored. The free-radical metabolites of thioridazine generated under UVA irradiation and its effects on ascorbate radical formation were examined with an electron paramagnetic resonance (EPR) spectrometer in vitro. As a result, immediate erythema developed during UVA irradiation in most subjects when 1% thioridazine was applied for 48 h and irradiation doses were higher than 4 J cm(-2). Another peak of erythematous reaction was observed 8-12 h after irradiation. The in vitro examination detected an apparent EPR signal, which appeared when 2 mM thioridazine in air-saturated phosphate buffer was irradiated with UVA, whereas this reaction was attenuated under anaerobic conditions. The EPR signal of the ascorbate radical was augmented under both aerobic and anaerobic conditions. Thioridazine-derived oxidants and/or thioridazine radicals generated during UVA irradiation seem to play an important role in this unique phototoxic reaction.

Planned complex suicide: report of three cases.

This article presents three planned complex suicide cases. The first case was a 46-year-old man, who had taken some antidepressant and antipsychotic drugs before cutting his right wrist and ingesting a large amount of concentrated hydrochloric acid. In the second case, a 34-year-old man was found dead in his home, hanging by his neck, with a suicidal stab wound on the left side of the chest. In the third case, a 22-year-old woman was found dead, hanging by her neck from a ceiling beam of her grandmother's a storage room, after taking of a solid rodenticide. The histories revealed psychiatric problems in all cases. The investigation of scene, the method employed, the autopsy findings and the interview with their relatives altogether pointed toward a suicidal etiology.

Progressive severe visual loss after long-term withdrawal from thioridazine treatment.

PURPOSE: To report advanced thioridazine-induced retinopathy in a 50-year-old woman with evidence of progressive severe loss of vision over 30 years after withdrawal from thioridazine treatment. METHODS: The ocular fundus examination revealed areas of retinal pigment epithelium (RPE) clumping as well as generalized atrophy of the RPE and choroid. The patient experienced visual loss to the level of no light perception in both eyes despite the fact that the funduscopic appearances of her optic nerves and retinal vasculature remained relatively normal. CONCLUSIONS: This case demonstrates that severe progressive visual loss can occur several years after the cessation of chronic thioridazine treatment.

Hypothermia Associated With Thioridazine Use in an Intellectually Disabled Patient.

PURPOSE: To report a case of hypothermia in a patient with intellectual disability treated with thioridazine. SUMMARY: A 59-year-old female presented to the emergency department with altered mental status, generalized weakness, chills, and fatigue and was diagnosed with a urinary tract infection. Upon completion of a history and physical examination, the patient was found to be hypothermic with a temperature of 91 F. A Bair Hugger protocol was initiated to manage hypothermia, and a taper schedule for thioridazine was initiated as it was identified as a possible culprit for the patient's hypothermia. According to the Naranjo probability scale, thioridazine was a possible cause of this adverse effect. Other patient-specific risk factors for hypothermia were evaluated and ruled out. CONCLUSION: This case indicates a possible correlation between hypothermia and the use of phenothiazine antipsychotics such as thioridazine. Appropriate measures, including early detection and identification of possible causative agents, should be taken to prevent and treat this adverse event in patients taking these medications, specifically in patients with the inability to participate in self-care.

Comparative effects of methylphenidate and thioridazine in hyperkinetic children. I. Clinical results.

The effects of three pharmacological treatments, methylphenidate hydrochloride, thioridazine hydrochloride, a methylphenidate/thioridazine combination, and placebo were studied in outpatient hyperkinetic children rated hyperactive both in school and at home or clinic. Active treatment lasted 12 weeks; placebo lasted four weeks. Significant clinical improvement was obtained in a variety of settings--all treatments were superior to placebo on ratings filled out by parents, teachers, and clinic staff. Though initially the combination of methylphenidate and thioridazine tended to produce greater clinical improvement, it was not superior to methylphenidate alone after 12 weeks of treatment. Methylphenidate alone and the methylphenidate/thioridazine combination were more effective than thioridazine alone. The salient side effects with methylphenidate treatment were decrease in appetite, difficulty in falling asleep, and increased mood sensitivity. In contrast, thioridazine administration was associated with appetite increase and enuresis.

Motility, Parkinsonism, and prolactin with thiothixene and thioridazine.

Clinical impressions suggest that thioridazine hydrochloride produces fewer extrapyramidal effects and more sedation than thiothixene. These drugs were given, each for three weeks, to 15 chronic schizophrenic outpatients in a counterbalanced, double-blind, crossover study. Spontaneous locomotion was recorded with an unobtrusive actometer toward the end of each three-week drug period. Surprisingly, patients were significantly more active with thioridazine, whereas parkinsonian scores, prolactin levels, and Brief Psychiatric Rating Scale scores remained about equal with the two drugs; thioridazine's extrapyramidal side effects were not "atypical." There are some explanations for why common clinical impressions and recent rodent studies have not predicted these results.

Differential effects of neuroleptic agents on the pituitary-gonadal axis in men.

Previous studies showing inconsistent effects of neuroleptic agents on the pituitary-gonadal system suggest that the drugs may differ in their effects on this system. Serum testosterone, luteinizing hormone (LH), prolactin, and neuroleptic levels were measured in 42 male schizophrenic patients during long-term treatment with thioridazine hydrochloride, trifluoperazine hydrochloride, chlorpromazine hydrochloride, and other neuroleptic agents and in six drug-free patients. Serum testosterone and LH values were significantly lower in patients taking thioridazine than in those taking other neuroleptic drugs. The relatively high serum neuroleptic levels in patients taking thioridazine may account for its differential effect on the pituitary-gonadal system.

Neuroleptic-induced seizures. An in vitro technique for assessing relative risk.

To estimate the relative risk of various neuroleptic medications for patients with epilepsy or likely to have neuroleptic-induced seizures, their action on spike activity in perfused guinea pig hippocampal slices was studied. Within the range of concentrations studied, molindone hydrochloride, butaclamol hydrochloride, pimozide, and fluphenazine dihydrochloride produced the least increase in excitability. There were also differences in the dose-response curves. Chlorpromazine, thioridazine, and pimozide produced an inverted U-shaped curve. For haloperidol and fluphenazine, excitability tended to increase and them plateau. Molindone and butaclamol produced no increase in excitability. Combinations of neuroleptics had synergistic effects, while the anticonvulsant diazepam inhibited neuroleptic-induced excitability. This article discusses the clinical implications of these findings and their effect on theories of which neuroleptics might produce the fewest seizures.

Physostigmine. Its use in acute anticholinergic syndrome with antidepressant and antiparkinson drugs.

We reviewed the use of physostigmine in the diagnosis and management of acute toxic psychosis due to drugs with anticholinergic properties. The syndrome of agitation and toxic confusional psychosis associated with peripheral signs of cholinergic blockade is produced by several plant toxins, antispasmodics, ophthalmic preparations, and certain proprietary sedatives, as well as antiparkinson medications, antidepressants, and some antipsychotic drugs. Physostigmine, uniquely among the available reversible anticholinesterase agents, can pass the blood-brain barrier to exert central as well as peripheral cholinomimetic actions to reverse this syndrome. Psychiatrists should make more use of this safe, specific, rapid, and effective treatment for anticholinergic drug toxicity, and should particularly be alert to reversible anticholinergic brain syndromes associated with antidepressants and antiparkinson medications, and even with antipsychotic medications.