Switching Selective Serotonin Reuptake Inhibitors in Adolescents with Selective Serotonin Reuptake Inhibitor-Resistant Major Depressive Disorder: Balancing Tolerability and Efficacy.

Objective: To guide clinicians in selecting the "next line" selective serotonin reuptake inhibitor (SSRI) for adolescents with treatment-resistant major depressive disorder, we sought to compare response rates among SSRIs in the Treatment of SSRI-Resistant Depression in Adolescents (TORDIA) study and to jointly model tolerability and efficacy for the specific SSRI comparisons. Methods: Efficacy and tolerability data for paroxetine, citalopram, and fluoxetine were extracted from the TORDIA study. Using a joint bivariate normal likelihood for response and tolerability (based on the maximum implied variance from the 95% credible intervals previously reported for the three SSRIs), a Monte Carlo pseudorandom sample (100,000 draws) was obtained, from which credible intervals, means, posterior tail probabilities, etc. were determined. Joint null hypotheses of no difference in efficacy and tolerability were then evaluated with regard to superiority of each SSRI over the others. Results: No significant differences in response were observed for citalopram compared with fluoxetine (p = 0.247) or for fluoxetine compared with paroxetine (p = 0.110), although citalopram trended toward being superior to paroxetine (mean difference: 0.2, p = 0.055). For efficacy-tolerability models, citalopram and fluoxetine were superior to paroxetine (p = 0.029 and p = 0.022, respectively) but did not differ between each other (p = 0.146). Conclusions: Joint efficacy-tolerability models suggest that citalopram and fluoxetine were statistically significantly superior to paroxetine while citalopram trended toward superiority over paroxetine in the efficacy model. These findings provide a more granular and practical evidence base for clinicians faced with treatment sequencing decisions in adolescents with SSRI-resistant depression.

Risk of Mortality in Elderly Nursing Home Patients with Depression Using Paroxetine.

OBJECTIVE: Among selective serotonin reuptake inhibitors (SSRIs), paroxetine is strongly anticholinergic and might lead to a higher risk of adverse outcomes such as mortality. This study examined the risk of mortality in depressed elderly nursing home patients using paroxetine and other SSRIs. METHODS: This study used 2007-2010 Minimum Data Set-linked Medicare data and a propensity score (PS)-matched retrospective cohort study design to achieve the study objective. New users of paroxetine and other SSRIs were followed until they reached the end of the follow-up period (1 year), switched to a different antidepressant class, used psychotherapy, or had a gap of more than 15 days in the use of index antidepressant class, whichever occurred earlier. A robust Cox proportional hazard (PH) model was used to evaluate the risk of mortality associated with the use of paroxetine and other SSRIs in depressed elderly nursing home residents. RESULTS: The PS matching yielded 4620 patients each in the two treatment groups. The unadjusted incidence of mortality was 269 (2.9%) for paroxetine and 288 (3.1%) for other SSRIs users in the matched cohort. The robust Cox PH model did not find any significant difference in the risk mortality between the two groups (hazard ratio 1.01; 95% confidence interval 0.86-1.19). CONCLUSIONS: This study did not find any significant difference in the risk of mortality between users of paroxetine and other SSRIs among elderly nursing home patients with depression. There is a need for further evaluation of other adverse effects of paroxetine due to its anticholinergic effects in the geriatric population.

Effect of database profile variation on drug safety assessment: an analysis of spontaneous adverse event reports of Japanese cases.

BACKGROUND: The use of a statistical approach to analyze cumulative adverse event (AE) reports has been encouraged by regulatory authorities. However, data variations affect statistical analyses (eg, signal detection). Further, differences in regulations, social issues, and health care systems can cause variations in AE data. The present study examined similarities and differences between two publicly available databases, ie, the Japanese Adverse Drug Event Report (JADER) database and the US Food and Drug Administration Adverse Event Reporting System (FAERS), and how they affect signal detection. METHODS: Two AE data sources from 2010 were examined, ie, JADER cases (JP) and Japanese cases extracted from the FAERS (FAERS-JP). Three methods for signals of disproportionate reporting, ie, the reporting odds ratio, Bayesian confidence propagation neural network, and Gamma Poisson Shrinker (GPS), were used on drug-event combinations for three substances frequently recorded in both systems. RESULTS: The two databases showed similar elements of AE reports, but no option was provided for a shareable case identifier. The average number of AEs per case was 1.6±1.3 (maximum 37) in the JP and 3.3±3.5 (maximum 62) in the FAERS-JP. Between 5% and 57% of all AEs were signaled by three quantitative methods for etanercept, infliximab, and paroxetine. Signals identified by GPS for the JP and FAERS-JP, as referenced by Japanese labeling, showed higher positive sensitivity than was expected. CONCLUSION: The FAERS-JP was different from the JADER. Signals derived from both datasets identified different results, but shared certain signals. Discrepancies in type of AEs, drugs reported, and average number of AEs per case were potential contributing factors. This study will help those concerned with pharmacovigilance better understand the use and pitfalls of using spontaneous AE data.

Incidence of type 2 diabetes among patients exposed to the combination of pravastatin and paroxetine.

PURPOSE: This study evaluated the effects of concomitant pravastatin and paroxetine use on the incidence of Type 2 Diabetes Mellitus (T2DM). METHODS: A new-user retrospective cohort design was employed using data selected from US health insurance claims databases (OptumInsight and MarketScan) between July 1, 2002, and December 31, 2009. Patients included were of age ≥18; newly prescribed pravastatin or paroxetine; and enrolled in the database for ≥180 days prior to the index date (i.e., first prescription of incident drug). Patients were assigned to either incident pravastatin or incident paroxetine user groups. Patients were followed until the study endpoint (T2DM), discontinuation of incident drug, second drug, or end of study/patient data. Cox proportional hazards models compared T2DM in users of pravastatin who were also taking paroxetine at index the date (combination users) versus pravastatinonly users. A similar analysis among users of paroxetine evaluated the use or non-use of pravastatin at index date. RESULTS: OptumInsight yielded 288,678 incident users of pravastatin or paroxetine; 443,137 were identified in MarketScan. The risk of T2DM among combination users compared to incident pravastatin only users was 1.05 (95% CI: 0.76, 1.44) and 0.94 (95% CI: 0.90, 0.97) in OptumInsight and MarketScan, respectively. The risk of T2DM among combination users compared to incident paroxetine only users was 1.03 (95% CI: 0.69, 1.54) in OptumInsight and 1.02 (95% CI: 0.97, 1.07) in MarketScan. CONCLUSION: The results indicate no increase in the risk of T2DM due to combined use of pravastatin and paroxetine compared to individual use of the two drugs; however, this study is limited by short mean follow-up.

Paroxetine versus other anti-depressive agents for depression.

BACKGROUND: Paroxetine is the most potent inhibitor of the reuptake of serotonin of all selective serotonin reuptake inhibitors (SSRIs) and has been studied in many randomised controlled trials (RCTs). However, these comparative studies provided contrasting findings and systematic reviews of RCTs have always considered the SSRIs as a group, and evidence applicable to this group of drugs might not be applicable to paroxetine alone. The present systematic review assessed the efficacy and tolerability profile of paroxetine in comparison with tricyclics (TCAs), SSRIs and newer or non-conventional agents. OBJECTIVES: 1. To determine the efficacy of paroxetine in comparison with other anti-depressive agents in alleviating the acute symptoms of Major Depressive Disorder.2. To review acceptability of treatment with paroxetine in comparison with other anti-depressive agents.3. To investigate the adverse effects of paroxetine in comparison with other anti-depressive agents. SEARCH METHODS: We searched the Cochrane Depression, Anxiety and Neurosis Review Group's Specialized Register (CCDANCTR, to 30 September 2012), which includes relevant randomised controlled trials from the following bibliographic databases: The Cochrane Library (all years), EMBASE (1974 to date), MEDLINE (1950 to date) and PsycINFO (1967 to date). Reference lists of relevant papers and previous systematic reviews were handsearched. Pharmaceutical companies marketing paroxetine and experts in this field were contacted for supplemental data. SELECTION CRITERIA: All randomised controlled trials allocating participants with major depression to paroxetine versus any other antidepressants (ADs), both conventional (such as TCAs, SSRIs) and newer or non-conventional (such as hypericum). For trials which had a cross-over design, only results from the first randomisation period were considered. DATA COLLECTION AND ANALYSIS: Two review authors independently checked eligibility and extracted data using a standard form. Data were then entered in RevMan 5.2 with a double-entry procedure. Information extracted included study and participant characteristics, intervention details, settings and efficacy, acceptability and tolerability measures. MAIN RESULTS: A total of 115 randomised controlled trials (26,134 participants) were included. In 54 studies paroxetine was compared with older ADs, in 21 studies with another SSRI, and in 40 studies with a newer or non-conventional antidepressant other than SSRIs. For the primary outcome (patients who responded to treatment), paroxetine was more effective than reboxetine at increasing patients who responded early to treatment (Odds Ratio (OR): 0.66, 95% Confidence Interval (CI) 0.50 to 0.87, number needed to treat to provide benefit (NNTb) = 16, 95% CI 10 to 50, at one to four weeks, 3 RCTs, 1375 participants, moderate quality of evidence), and less effective than mirtazapine (OR: 2.39, 95% CI 1.42 to 4.02, NNTb = 8, 95% CI 5 to 14, at one to four weeks, 3 RCTs, 726 participants, moderate quality of evidence). Paroxetine was less effective than citalopram in improving response to treatment (OR: 1.54, 95% CI 1.04 to 2.28, NNTb = 9, 95% CI 5 to 102, at six to 12 weeks, 1 RCT, 406 participants, moderate quality of evidence). We found no clear evidence that paroxetine was more or less effective compared with other antidepressants at increasing response to treatment at acute (six to 12 weeks), early (one to four weeks), or longer term follow-up (four to six months). Paroxetine was associated with a lower rate of adverse events than amitriptyline, imipramine and older ADs as a class, but was less well tolerated than agomelatine and hypericum. Included studies were generally at unclear or high risk of bias due to poor reporting of allocation concealment and blinding of outcome assessment, and incomplete reporting of outcomes. AUTHORS' CONCLUSIONS: Some possibly clinically meaningful differences between paroxetine and other ADs exist, but no definitive conclusions can be drawn from these findings. In terms of response, there was a moderate quality of evidence that citalopram was better than paroxetine in the acute phase (six to 12 weeks), although only one study contributed data. In terms of early response to treatment (one to four weeks) there was moderate quality of evidence that mirtazapine was better than paroxetine and that paroxetine was better than reboxetine. However there was no clear evidence that paroxetine was better or worse compared with other antidepressants at increasing response to treatment at any time point. Even if some differences were identified, the findings from this review are better thought as hypothesis forming rather than hypothesis testing and it would be reassuring to see the conclusions replicated in future trials. Finally, most of included studies were at unclear or high risk of bias, and were sponsored by the drug industry. The potential for overestimation of treatment effect due to sponsorship bias should be borne in mind.

Detecting drug interactions from adverse-event reports: interaction between paroxetine and pravastatin increases blood glucose levels.

The lipid-lowering agent pravastatin and the antidepressant paroxetine are among the most widely prescribed drugs in the world. Unexpected interactions between them could have important public health implications. We mined the US Food and Drug Administration's (FDA's) Adverse Event Reporting System (AERS) for side-effect profiles involving glucose homeostasis and found a surprisingly strong signal for comedication with pravastatin and paroxetine. We retrospectively evaluated changes in blood glucose in 104 patients with diabetes and 135 without diabetes who had received comedication with these two drugs, using data in electronic medical record (EMR) systems of three geographically distinct sites. We assessed the mean random blood glucose levels before and after treatment with the drugs. We found that pravastatin and paroxetine, when administered together, had a synergistic effect on blood glucose. The average increase was 19 mg/dl (1.0 mmol/l) overall, and in those with diabetes it was 48 mg/dl (2.7 mmol/l). In contrast, neither drug administered singly was associated with such changes in glucose levels. An increase in glucose levels is not a general effect of combined therapy with selective serotonin reuptake inhibitors (SSRIs) and statins.

Paroxetine mesylate: comparable to paroxetine hydrochloride?

IMPORTANCE OF THE FIELD: Currently available small case reports clearly propose that existing regulatory procedures to approve generic versions only require essential bioequivalence, have limitations and fail to meet stricter scientific and clinical demands. AREAS COVERED IN THIS REVIEW: Data indicate that paroxetine mesylate has some potential differences in bio- and clinical equivalence compared with paroxetine hydrochloride, although it has not been fully and sufficiently investigated in well-designed clinical trials. Data available now regarding safety, tolerability, efficacy and practical issues dealing with debates between generic and brand-name products paroxetine mesylate and paroxetine hydrochloride are presented in the review. WHAT THE READER WILL GAIN: Preclinical and clinical data are reviewed, and clinical issues relating to use of generic version versus original product are comprehensively discussed; tips for the clinician in clinical practice are also provided. TAKE HOME MESSAGE: Potential differences in efficacy and safety but also reduction in the use of health care and in pharmacy cost should be considered when choosing the generic version or the original product based on the clear benefit-risk ratio in patients.

Seroxat and the suppression of clinical trial data: regulatory failure and the uses of legal ambiguity.

This article critically evaluates the Medicines and Healthcare products Regulatory Agency's announcement, in March 2008, that GlaxoSmithKline would not face prosecution for deliberately withholding trial data, which revealed not only that Seroxat was ineffective at treating childhood depression but also that it increased the risk of suicidal behaviour in this patient group. The decision not to prosecute followed a four and a half year investigation and was taken on the grounds that the law at the relevant time was insufficiently clear. This article assesses the existence of significant gaps in the duty of candour which had been assumed to exist between drugs companies and the regulator, and reflects upon what this episode tells us about the robustness, or otherwise, of the UK's regulation of medicines.

Effects of milnacipran and paroxetine on overactive bladder due to neurologic diseases: a urodynamic assessment.

AIMS: To determine the effects of milnacipran hydrochloride, a serotonin-norepinephrine reuptake inhibitor (SNRI), or paroxetine hydrochloride, a selective serotonin reuptake inhibitor, on overactive bladder (OAB) in neurologic diseases, given by objective measures of urodynamic studies. METHODS: This is a prospective open trial, and we enrolled 24 patients (16 men, 8 women; mean age, 63.9 years) with OAB in a neurology clinic. They were randomly allocated into two groups: the milnacipran group (11 patients), and paroxetine group (13 patients). We started with 100 mg/day of milnacipran or 40 mg/day of paroxetine. Before and 3 months after the treatment, we performed a urinary questionnaire and urodynamic studies. RESULTS: Milnacipran reduced daytime urinary frequency (average, from 9.4 to 7.1 times, p < 0.001), improved the quality of life index (p = 0.023), and increased bladder capacity (average, from 289 to 377 ml, p = 0.009) as shown in urodynamic studies. No such changes were noted in the other categories of the lower urinary tract symptoms questionnaire or urodynamic studies, or in the paroxetine group. One male patient complained of mild voiding difficulty. Other adverse effects were not seen during the observation period. CONCLUSION: Milnacipran, an SNRI, increased bladder capacity as shown in urodynamic studies, and thereby ameliorated OAB in patients with neurologic diseases without serious adverse effects.

Industry-sponsored ghostwriting in clinical trial reporting: a case study.

In this case study from litigation, we show how ghostwriting of clinical trial results can contribute to the manipulation of data to favor the study medication. Study 329 for paroxetine pediatric use was negative for efficacy and positive for harm. Yet the ghostwritten publication from this study concluded that paroxetine provided evidence of efficacy and safety and continues to be influential. Despite the role of named authors in revisions of the manuscript, the sponsor company remained in control of the message.

SSRI antidepressants and birth defects.

(1) Between 20% and 30% of newborns exposed to selective serotonin reuptake inhibitor antidepressants (SSRIs) towards the end of gestation have disorders such as agitation, abnormal muscle tone and suction, seizures and hyponatraemia. (2) Worrisome data concerning a possible teratogenic effect were published in late 2005. (3) In a Danish cohort including 1054 pregnant women, the estimated relative risk of all congenital malformations, compared with the general population, among the offspring of women who received a prescription for an SSRI was 1.4 (95% CI 1.1-1.9), and the relative risk of cardiac malformations was 1.6 (95% CI 1.0-2.6). (4) An American retrospective study compared the newborns of women who were prescribed paroxetine during the first trimester of pregnancy with all newborns exposed to other antidepressants: 4% of newborns exposed to paroxetine had malformations (2% had cardiac malformations). The estimated relative risk for all congenital malformations was 2.20 (95% CI 1.34-3.63), and the estimated relative risk of cardiovascular malformations was 2.08 (95% CI 1.03-4.23). (5) Analysis of a Swedish birth register provided an estimated relative risk of cardiac malformations associated with paroxetine of 2.22 (95% CI 1.39-3.55) compared with the general population. (6) Another American study showed a global increase in the risk of malformations with paroxetine compared with all antidepressants. The risk of cardiovascular malformations was not significantly increased. (7) In a case-control study based on an American register of birth defects, the estimated relative risk of omphalocele was 3.0 with all SSRIs (95% CI 1.4 to 6.1), and the estimated relative risk of craniosynostosis was 1.8 (95% CI 1.0-3.2). (8) In practice, all SSRIs have been implicated in a possible increase in the risk of congenital malformations, but the most worrisome evidence concerns paroxetine. This potential risk implies that the justification for paroxetine treatment in pregnant women should be carefully weighed; this means double-checking the diagnosis, the potential benefits and adverse effects, and possible alternatives.

Even more suicide attempts in clinical trials with paroxetine randomised against placebo.

BACKGROUND: Following our previous publication we have received critical comments to our conclusions as well as new data that are strengthening our findings. RESULTS: With the new data, 11 suicide attempts among patients on paroxetine against 1 among patients on placebo, we found with a Bayesian technique that the posterior probability that medication with paroxetine is associated with an increased intensity per year of a suicide attempt is from 0.98 to 0.99, depending on the prior. We found that the comment to our article by GSK representatives contained errors, misunderstanding and unwillingness to accept Bayesian principles in the analysis of clinical trials. CONCLUSION: We were in our previous publication, with preliminary data and a Bayesian approach, able to raise a concern that suicide attempts might be connected with the use of paroxetine. This suspicion has now been confirmed.