International Life Sciences Institute (Health and Environmental Sciences Institute, HESI) initiative on moving towards better predictors of drug-induced torsades de pointes.

Knowledge of the cardiac safety of emerging new drugs is an important aspect of assuring the expeditious advancement of the best candidates targeted at unmet medical needs while also assuring the safety of clinical trial subjects or patients. Present methodologies for assessing drug-induced torsades de pointes (TdP) are woefully inadequate in terms of their specificity to select pharmaceutical agents, which are human arrhythmia toxicants. Thus, the critical challenge in the pharmaceutical industry today is to identify experimental models, composite strategies, or biomarkers of cardiac risk that can distinguish a drug, which prolongs cardiac ventricular repolarization, but is not proarrhythmic, from one that prolongs the QT interval and leads to TdP. To that end, the HESI Proarrhythmia Models Project Committee recognized that there was little practical understanding of the relationship between drug effects on cardiac ventricular repolarization and the rare clinical event of TdP. It was on that basis that a workshop was convened in Virginia, USA at which four topics were introduced by invited subject matter experts in the following fields: Molecular and Cellular Biology Underlying TdP, Dynamics of Periodicity, Models of TdP Proarrhythmia, and Key Considerations for Demonstrating Utility of Pre-Clinical Models. Contained in this special issue of the British Journal of Pharmacology are reports from each of the presenters that set out the background and key areas of discussion in each of these topic areas. Based on this information, the scientific community is encouraged to consider the ideas advanced in this workshop and to contribute to these important areas of investigations over the next several years.

New antiarrhythmic agents. 2. Amide alkyl alpha-amino xylidides.

The synthesis of a series of N-alkyl 2-amino 2',6'-xylidides is described. The method involved coupling of the N-alkyl-2',6'-xylidine with the appropriate 2-haloacyl halide, followed by ammonolysis. Alternatively, alkylation of the 2-phthalimido 2',6'-xylidide with NaH and the alkyl halide followed by hydrazinolysis was used. All compounds were evaluated for their ability to protect mice against chloroform-induced ventricular fibrillation. The compounds were generally more potent antifibrillatory agents than the corresponding secondary amides. All were more potent than tocainide and several showed less CNS toxicity. Five compounds were further evaluated in dogs with ventricular arrhythmias resulting from myocardial infarction. N-Ethyl-2-aminoaceto-4'-propoxy-2',6'-xylidide was as potent as lidocaine and produced less CNS toxicity.

New antiarrhythmic agents. 3. Primary beta-amino anilides.

The synthesis and pharmacologic evaluation of primary beta-amino anilides, as well as comparisons with tocainide, lidocaine, and its beta homologue, are described. Substituted anilines were acylated with 3-bromoacyl chlorides and converted to the title compounds by direct amination or via 3-phthalimido anilides and subsequent hydrazinolysis. Alternatively, anilines were acylated with substituted acryloyl chlorides and the amines prepared by addition of ammonia to the double bond. The target compounds were evaluated for their ability to protect against chloroform-induced fibrillation in mice. All were found to have some antifibrillatory activity; several were more potent than tocainide, a compound in clinical trials as an oral antiarrhythmic drug. Four compounds were tested for their effects against ventricular arrhythmias in dogs with myocardial infarction. 3-Amino-2',6'-butyroxylidide (38) was found to be more potent and less CNS toxic than tocainide.

New antiarrhythmic agents. 4. 1'-(Aminoalkyl)-1,2,3,4-tetrahydronaphthalene-1-spiro-3'-pyrrolidine-2',5'-dione derivatives.

A series of 33 1'-(Aminoalkyl)-1,2,3,4-tetrahydronaphthalene-1-spiro-3'-pyrrolidine-2',5'-dione derivatives was tested for antiarrhythmic and toxic effects in mice and dogs. In mice, 31 compounds produced some protection against chloroform-induced tachyarrhythmias at subcutaneous doses of 100 mg/kg, and 6 compounds produced no detectable toxicity at doses protecting 80% or more of the animals. Seven of the more potent and nontoxic derivatives were tested in dogs with surgically induced myocardial infarctions. All produced distinct antiarrhythmic effects at doses considerably lower than doses of lidocaine or tocainide producing comparable effects. The principal toxic effects observed in dogs were convulsion and depression of intracardiac conduction; they occurred generally at higher doses than those leading to antiarrhythmic effect. Several compounds also suppressed digitalis-induced arrhythmias in anesthetized dogs. Half-lives and total body clearance in dogs were determined for three compounds; two had half-lives comparable to that of tocainide, a long-acting, orally active antiarrhythmic agent, in clinical trials.

New antiarrhythmic agents. 1. Primary alpha-amino anilides.

Thirty-two alpha-amino anilides with various substituents in the aromatic ring and in the alpha position are described. Their abilities to protect mice against chloroform-induced fibrillation and to elicit toxicity were determined. Substitution of an alkyl or aryl group in the alpha position enhanced the antifibrillatory activity. In most cases, increased potency was accompanied by increased toxicity. Eleven compounds were tested in dogs with surgically induced myocardial infarction; most showed antiarrhythmic activity. 2-Aminopropiono-2',6'-xylidide, tocainide, was chosen for clinical investigation.

Loxapine succinate as initial treatment of hostile and aggressive schizophrenic criminal offenders.

The efficacy and safety of loxapine were evaluated in 18 acutely ill schizophrenic criminal offenders in the Essex County Jail. The offender patients were treated for three days with intramuscular loxapine (25 mg three or four times a day), followed by seven days of oral concentrate (up to 150 mg/day in three or four divided doses). Psychiatric status was determined with the Brief Psychiatric Rating and the Clinical Global impression scales at the time of admission, after 8, 24, 48, and 72 hours, amd on days 7 and 10 of medication. Three patients did not complete treatment: one was released on bail after 24 hours of therapy, and the other two had adverse reactions (tongue swelling and muscle spasms, each in one patient) which required cessation of treatment. Statistically significant improvement in both rating scale results was evident as early as 8 hours after treatment began. By day 10, all Brief Psychiatric Rating Scale items and factors and the Clinical Global impression results were statistically improved over baseline measurements. At the end of the study, 87 per cent (13/15) of the patients were well enough to cooperate with their attorneys and understand the procedures of the court. Adverse effects (generally extrapyramidal) appeared in four of 18 patients during parenteral administration and in two of 15 patients during oral therapy.

Family therapy: its role in the prevention of criminality.

The family imprints its members with selfhood in all cultures. Absence of family imprints can result in the development of deviant childhood behavior and loss of identity. In two black racial groups in dissimilar world areas and sampling (Kenya, Africa and Newark, N.J.), five familial determinants interfered with the development of culturally accepted family imprints and led to deviant and criminal behavior. It is suggested that if these deterrents, namely poverty, lack of family authority figures, rejection of of the individual child, absence of family cohesiveness, and loss of individual identity within the family, were altered in their development by family therapy techniques, then criminal and deviant behavior would be decreased.