The effect of the MAO-A selective inhibitor brofaromine on the plasma and urine concentrations of some biogenic amines and their acidic metabolites in bulimia nervosa

Antidepressants versus placebo for people with bulimia nervosa

BACKGROUND

Bulimia Nervosa (BN) represents an important public health problem and is related to serious morbidity and even mortality. This review attempted to systematically evaluate the use of antidepressant medications compared with placebo for the treatment of bulimia nervosa.

OBJECTIVES

The primary objective of this review was to determine whether using antidepressant medications was clinically effective for the treatment of bulimia nervosa. The secondary objectives were: (i) to examine whether there was a differential effect for the various classes/types of antidepressants with regard to effectiveness and tolerability (ii) to test the hypothesis that the effect of antidepressants on bulimic symptoms was independent of its effect on depressive symptoms

SEARCH STRATEGY

(1) electronic searches of MEDLINE (1966 to December 2000), EMBASE (1980-December 2000), PsycLIT (to December 2000), LILACS & SCISEARCH (to 1997) (2) the Cochrane Register of Controlled Trials and the Cochrane Depression, Anxiety and Neurosis Group Register - ongoing (3) inspection of the references of all identified trials (4) contact with the pharmaceutical companies and the principal investigator of each included trial (5) inspection of the International Journal of Eating Disorders - ongoing

SELECTION CRITERIA

INCLUSION CRITERIA

every randomized, placebo-controlled trial in which antidepressant medications were compared to placebo to reduce the symptoms of bulimia nervosa in patients of any age or gender. Quality criteria: reports were considered adequate if they were classified as A or B according to the Cochrane Manual. The Jadad scale, with a cut off of 2 points, was applied to check the validity of the above referred criterion but was not used as an inclusion criterion.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two reviewers for each included trial. Dichotomous data were evaluated by the relative risk with 95% confidence intervals (CI) around this measure, based on the random effects model; continuous data were evaluated by the standardised mean difference with the 95% CI. NNT was calculated using the inverse of the absolute risk reduction.

MAIN RESULTS

Currently the review includes 16 trials comparing antidepressants with placebo: 6 trials with TCAs (imipramine, desipramine and amitryptiline), 3 with SSRIs (fluoxetine), 4 with MAOIs (phenelzine, isocarboxazid and brofaromine) and 3 with other classes of drugs (mianserine, trazodone and bupropion). Similar results were obtained in terms of efficacy for these different groups of drugs. The pooled RR for remission of binge episodes was 0.88 (95% CI 0.83-0.93; p<0,001) favoring drugs. The NNT for a mean treatment duration of 8 weeks, taking the non-remission rate in the placebo controls of 92% as a measure of the baseline risk was 9 (95% CI 6 - 16). The RR for clinical improvement, defined as a reduction of 50% or more in binge episodes was 0.63 (95% CI 0.55-0.74) and the NNT for a mean treatment duration of 9 weeks was 4 (95% CI 3 - 6), with a non-improvement rate of 67% in the placebo group. Patients treated with antidepressants were more likely to interrupt prematurely the treatment due to adverse events. Patients treated with TCAs dropped-out due to any cause more frequently that patients treated with placebo. The opposite was found for those treated with fluoxetine, suggesting it may be a more acceptable treatment. Independence between antidepressant and antibulimic effects could not be evaluated due to incomplete published data.

REVIEWER'S CONCLUSIONS

The use of a single antidepressant agent was clinically effective for the treatment of bulimia nervosa when compared to placebo, with an overall greater remission rate but a higher rate of dropouts. No differential effect regarding efficacy and tolerability among the various classes of antidepressants could be demonstrated.

Pharmacokinetic and pharmacodynamic interactions between fluoxetine and moclobemide in the investigation of development of the "serotonin syndrome"

OBJECTIVE

To assess the tolerability, safety, pharmacokinetics, and pharmacodynamics of combined treatment with fluoxetine and moclobemide in healthy subjects.

METHODS

Fluoxetine (20 to 40 mg/day) was administered for 23 days to 18 subjects. At (nor)fluoxetine steady state, subjects were randomized in a 2:1 ratio to receive in addition either moclobemide (ascending doses up to 600 mg/day) of placebo. A single 300 mg dose of moclobemide was administered before and at the end of the fluoxetine regimen to assess the effects of the latter on the pharmacokinetics and pharmacodynamics of moclobemide. Adverse events and vital signs were recorded and pharmacokinetic parameters of fluoxetine and moclobemide were determined. Plasma concentrations of 3,4-dihydroxy-phenyl-glycol, 5-hydroxyindoleacetic acid, 3,4-dihydroxyphenylacetic acid, and serotonin uptake into platelets were assessed as pharmacodynamic measures.

RESULTS

The number, intensity, or type of adverse events did not change when moclobemide was added to fluoxetine. No clinically relevant changes in safety parameters occurred. Fluoxetine markedly inhibited the metabolism of moclobemide. However, multiple dosing of moclobemide did not lead the excessive accumulation. 3,4-Dihydroxyphenylglycol, 5-hydroxyindoleacetic acid, and 3,4-dihydroxyphenylacetic acid plasma levels and serotonin uptake did not reveal a pharmacodynamic interaction.

CONCLUSIONS

Combination treatment with fluoxetine and moclobemide did not provide any indication of development of the "serotonin syndrome."

Effects of chronic brofaromine administration on biogenic amines including sulphatoxymelatonin and acid metabolites in patients with bulimia nervosa

Brofaromine, a selective and reversible inhibitor of monoamine oxidase-A (MAO-A) was given to 19 women while 17 received placebo for 8 weeks. All met DSM III-R criteria for bulimia nervosa, a psychiatric disorder in which uncontrolled overeating episodes are accompanied by purging activities and extreme concerns about body shape and weight. The following indices were measured: plasma and urinary phenylacetic acid (PAA), homovanillic acid (HVA), vanillylmandellic acid (VMA); plasma tryptamine (T), beta phenylethylamine (PE), and 5-hydroxyindoleacetic acid (5-HIAA) and urinary 6-sulphatoxymelatonin (aMT6s). PE levels remained the same but T showed a trend toward elevation over time. Twenty-four hour levels of urinary aMT6s in BN patients were higher at week 4 when compared to baseline and week 8. There was a significant reduction in plasma VMA and HVA over time during treatment with brofaromine and both plasma HVA and VMA were significantly lower for the brofaromine group compared to placebo at week 4. Plasma 5-HIAA was significantly higher for the brofaromine group after 8 weeks when compared to placebo. Urinary VMA decreased significantly from baseline to week 4 with a partial elevation at 8 weeks. Urinary VMA was also significantly lower in patients on brofaromine at week 4. This study verifies that brofaromine complies with predicted MAO-A inhibiting patterns in a clinical population.