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California Association of Toxicologists Annual Meeting (June 9, 2006) Safety and Efficacy of Antidepressants and Antipsychotics too Patrick R. Finley, Pharm.D. BCPP Professor of Clinical Pharmacy Psychopharmacology and Behavioral Health University of California at San Francisco e-mail: [email protected] Efficacy of Antidepressants in Treating Major Depression 100% 80% 60% 65% 40% 35% 20% 0% Therapeutic Response >50% decrease sx Achieve Remission HAMD < 7 Evaluation of Outcomes with Citalopram for Depression Using Measurement-Based Care in STAR*D: Implications for Clinical Practice Trivedi MH et al. Am J Psychiatry 2006; 163:5-7 Methods – 2876 depressed patients enrolled from 23 psychiatric, 18 primary care settings into rigid treatment protocol – Pts treated initially with citalopram for up to 14 weeks – Pts randomized to other treatment thereafter if unsuccessful Results (Level 1) – – – – – Avg of 4.8 visits during tx phase Avg citalopram dose = 41.8 mg/day 33 % achieved remission ( 5 on QIDS-SR) 47 % had therapeutic response ( 50% decline QIDS-SR) 4.1% had serious adverse effects (no suicides reported) The majority of patients prescribed antidepressants will need a change in their regimen* * - dosage adjustment, augmentation, or switch antidepressants Outcomes of Depressed Patients: Therapeutic Response vs Remission Pts Maintaining Response Paykel et al. Psychol Med 1995 1 0.8 Remission (HAMD<7) Residual Sx (HAMD>7) 0.6 0.4 0.2 0 0 2 4 6 Months 8 10 12 Residual Symptoms of Depressed Patients Who Respond Acutely to Fluoxetine (n=108) Nierenberg A et al. J Clin Psychiatry 1999;60:221-225. 40 30 20 10 nt ra Su tio ici n da lI de at io n Gu ilt Co nc e tig ue Fa ot or om Ps yc h Sl ee p t W eig h In te re st oo d 0 M Percentage of Patients 50 Suggestion #1: Go for the Gold !! (ie – remission) Suggestion #2: Don’t Forget About Psychotherapy Antidepressant Selection May be Influenced by the Following: Family History Adverse Effects Medical Co-Morbidities Psychiatric Co-morbidities Depression Subtypes – Anergic/Amotivational – Anxious/Irritable – Severe or Tx-Resistant Gender Other (drug interactions, cost etc) SSRI: Common Adverse Effects Gastrointestinal – nausea, diarrhea (fluox, sert), constipation (parox) Central Nervous System – – headache insomnia/agitation >>> sedation Hierarchy: fluox > sert > escital > cital > parox > fluvox [Prozac > Zoloft > Lexapro > Celexa > Paxil > Luvox} Sexual Effects SSRI/SNRI and Sexual Dysfunction Epidemiology Approximate incidence (new-onset) = 50 % (range: 2 % - 75 %); Hierarchy: parox > fluox sert, cital, escital > fluvox Incidence slightly higher in men (?) Severity slightly higher in women (?) Types of Sexual Dysfunction – – – libido problems more common with depression orgasm problems more common with antidepressant (eg - delayed ejaculation or anorgasmia) erectile problems uncommon with SSRI [Patient Counseling: ‘This medication may change your sexual functioning’] Effect of SSRI Antidepressants on Ejaculation Waldinger et al. J Clin Psychopharmacol 1998; 18:274-81. Methods – Double-blind placebo-controlled RCT – Compared effects of fluoxetine (20mg), fluvoxamine (100mg), paroxetine (20mg) and sertraline (50mg) on ejaculatory delay – Patient Population: men with premature ejaculation (n=60) Results (increase in ejaculatory latency time from baseline) – fluoxetine paroxetine sertraline fluvoxamine = 117 secs* (p < 0.001) = 100 secs* (p < 0.001) = 65 secs* (p = 0.017) = 9 secs – placebo = – – – 7 secs * statistically significant difference SSRI/SNRI and Sexual Dysfunction Management Patience Drug holidays (?) Reduce dose Antidotes (ie - augmentation) – Examples: bupropion, sildenafil, amantadine, buspirone, yohimbine, cyproheptadine, nefazodone, stimulants, granisetron, gingko biloba Switching antidepressants – Examples: bupropion, mirtazapine SSRI: Other Adverse Effects Sweating Bruxism Weight Gain Extrapyramidal Side Effects SIADH GI Bleeds (?) Suicide (?) Prozac Poop-out (ie – tachyphylaxis)? Fluoxetine Versus Sertraline and Paroxetine in Major Depressive Disorder: Changes in Weight with Long-term Treatment [7 month RCT; n=139] Fava M et al. J Clin Psychiatry 2000; 61:863-867 30 25 Pct > 7% gain 20 15 10 5 0 Fluoxetine 42 mg/d Sertraline 94 mg/d Paroxetine 37 mg/d Use of Selective Serotonin Reuptake Inhibitors and Risk of Upper Gastrointestinal Bleeding Dalton SO et al. Arch Intern Med 2003; 163:59-64 Observed/Expected (O/E) Ratio for GI Bleeds 13 11 9 O/E Antidepressant 7 5 Antidepressant + NSAID 3 1 SSRI (20/7565) TCA (13/4778) Other (4/2117) Antidepressants and Suicide What’s the Evidence ? Adults – 2% of outpatients & 4% of inpatients treated for depression will commit suicide – 5-15 % of patients with untreated depression will commit suicide – Clinical trials: > 20,000 adult subjects received SSRI in trials Significant decline in suicidality reported Study limitations are substantial – – – – – homogenous patient populations suicidality assessed by 1 item embedded in depression rating scales (eg–HAMD) inconsistent definition of suicidal behavior brief follow-up period distinguish treatment effect from withdrawal effect Antidepressants and Suicide What’s the Evidence ? Children and Adolescents – Suicide is 3rd leading cause of death in adolescents – Suicide rate 33% over last 10-14 years – Clinical trials (Columbia study) 4,250 children in 25 studies of 9 antidepressants No successful suicides reported Nonsignificant increase in suicidal behavior (RR=1.78) – Effexor, Paxil > Celexa, Zoloft Prozac Antidepressants and Suicide Why would risk be greater in children & adolescents than adults ? Artifact (ie - preliminary data only) Depressed children/adolescents are more impulsive Children are receiving proportionately higher doses Antidepressants have different PK/PD properties in children Greater influence/activity of 5HT system in children Antidepressants and Suicide Summary Preliminary data in children and adolescents suggests higher risk of suicidal behavior after initiation (or dosage change) with ALL antidepressants Increased suicidal behavior may be attributed to – lack of response to prescribed antidepressant – extreme agitation or akathisia – delayed response (somatic sx better before cognitive) – misdiagnosis (eg - bipolar depression, personality d/o) Pharmaceutical manufacturers should be required to disclose ALL results of clinical trials Clinical trial methodology is antiquated – naturalistic element must be integrated into RCT – more sensitive measures of suicidal behavior needed – patient population must be more representative Untreated depression much more likely to induce suicide than any antidepressant SSRI Withdrawal Phenomenon Symptoms: dizziness lethargy nausea paresthesias insomnia Onset: 48-72 hours Duration: 5-7 days Worse with paroxetine, venlafaxine Minimal risk with fluoxetine Serotonin Syndrome Rare, idiosyncratic, sometimes fatal Mechanism: 5HT excess Symptoms: – MS changes, chills/sweating, myoclonus, autonomic instability ( or BP & HR), fever (malignant hyperthermia) Medications: – Most Commonly Associated: MAOI (Nardil, Parnate) Commonly Associated: SSRI (all), Clomipramine (Anafranil), Venlafaxine (Effexor), Tramadol (Ultram), Selegiline, Sibutramine (Meridia), Detromethorphan Occasionally Associated: Meperidine (Demerol), Trazodone – Rarely Associated: Sumatriptan (Imitrex), St. John’s Wort – – Clinical Significance of Drug Interactions with SSRI potent inhibitors of Cytochrome P450 significant differences among SSRI @ potential – Cyt 1A2: fluvox >> fluox, parox, sert, cital, escital substrates: TCA, haldol, clozapine, olanzapine, theophylline – Cyt 2D6: fluox, parox, dulox, buprop >> sert, cital, escital substrates: -blockers, narcotics (codeine, hydrocodone, tramadol), TCA – Cyt 3A4: norfluox, fluvox >> fluox, parox, sert, cital, escital substrates: CCB, estrogen, corticosteroids, statins, protease inhibitors, alprazolam, triazolam, buspirone, sildenafil in vitro affinity different than in vivo wide interpatient variability Suggestion #3: Do No Harm SSRI: Dosing Guidelines for Primary Care* *note: Dosing may be higher for severe depression or in psychiatric settings SSRI – – – – – – Fluoxetine Sertraline Paroxetine Citalopram Escitalopram Fluvoxamine Recommendation: Initial Dose Maintenance Dose 10 mg 25 mg 10 mg 10 mg 5 mg 25 mg 10 25 10 10 5 50 – 20 mg/d – 100 mg/d – 20 mg/d – 20 mg/d – 10 mg/d – 200 mg/d (divided) Take with breakfast exception: take fluvoxamine at HS VENLAFAXINE (Effexor ®) Therapeutic Use MOA: blocks reuptake of 5HT and NE (dose-dependent) Adverse Effects: similar to SSRI* (including withdrawal) – *note: HTN commonly seen with doses > 150 mg/d Dosing & Administration – – – – Initiate treatment at 37.5 mg QD (XR) Usual therapeutic dose = 75 - 225 mg/d Maximum Daily Dose XR (package insert) = 225mg/day (?!) May be preferred if Severe or treatment-resistant depression Incidence of Sustained Hypertension with Venlafaxine* (Effexor Package Insert, Wyeth 2004) * - defined as Diastolic BP > 90 AND change in Diastolic BP > 10 x 3 consecutive visits 14% 12% 10% 8% 6% 4% 2% 0% 100 mg/d 300 mg/d > 300 mg/d DULOXETINE (Cymbalta®) Therapeutic Use MOA: blocks reuptake of 5HT and NE Adverse Effects: similar to SSRI* (including withdrawal) – hepatotoxicity (1.0% incidence of 3-fold in ALT Pharmacokinetics: vs 0.2% placebo) – Plasma Half-life = 12 hrs; linear – Cytochrome P450 2D6 inhibitor Dosing & Administration – Initiate treatment at 30 mg/d – Usual therapeutic dose = 60 mg/d – May be preferred if severe or treatment-resistant depression – Other Indications: neuropathic pain BUPROPION (Wellbutrin® or Zyban ®) Therapeutic Use MOA: enhances NE/DA transmission Adverse Effects: insomnia, HA, nausea, rash, seizures – Contraindications: h/o eating d/o, seizure d/o Dosing & Administration – Sustained-release (SR): initiate with 150mg in AM and increase to 150mg BID after 3 days; Doses must be separated by 8hrs; Maximum daily dose = 400mg – Extended-release (XL): initiate with 150mg in AM and increase to 300mg in AM after 3 days; Doses must be separated by 24 hrs; Maximum daily dose = 450 mg – May be preferred if low energy, predominant anhedonia pt requests med without sex dysfunction or weight gain SSRI augmentation MIRTAZAPINE (Remeron®) Therapeutic Use MOA: blocks 2 receptors, 5HT2, 5HT3 receptors Adverse Effects: sedation, weight gain, chol/TG Dosing & Administration – Initiate treatment with 15mg HS – Maximum daily dose = 45 mg (?) note: 30mg associated with less sedation – May be preferred if tx-resistant depression pts with sex dysfunction weight gain or sedation desirable Suggestion #3: Tailor Antidepressant to Specific Patient Targeted Treatment of Depression Medical Comorbidity Psychiatric Comorbidity Depression Subtype Prevalence of Depression with Medical Illnesses* * - Point prevalence; Mean of range cited when applicable Finley PR. Rx Consultant 2004; 13 (6):1-8 50% 40% 30% 20% 10% 0% en tia V HI ons s in rk Pa m De y ps ile Ep r ke ro St l pu Po s te be e nc Ca a Di D CA l ra ne Ge n io at Antidepressants and Medical Co-Morbidity Cardiovascular Disease Hypertension SNRI (venlafaxine, duloxetine) - increased blood pressure/heart rate bupropion - increased blood pressure/heart rate Cerebrovascular Disease TCA - increased risk of cardiac events SSRI – decrease risk of cardiac events (?) fluoxetine, paroxetine, duloxetine, bupropion - inhibit metabolism of beta blockers norfluoxetine, fluvoxamine - inhibit metabolism of Ca channel blockers TCA - superior efficacy vs SSRI (?) SSRI – preliminary efficacy in prophylaxis Diabetes TCA, mirtazapine, paroxetine - weight gain norfluoxetine, fluvoxamine, nefazodone - inhibit metabolism of sulfonylureas Antidepressants and Medical Co-Morbidity: Continued Breast Cancer, Menopause Parkinson’s Disease SSRI, SNRI – may increase bleeding risk (?) Dementia bupropion - may benefit dopamine transmission Peptic Ulcer Disease SSRI, SNRI - may benefit hot flashes TCA, paroxetine – avoid antidep with antichol effects SSRI, bupropion – may be less likely to cloud sensorium AIDS fluvoxamine, nefazodone - inhibit metabolism of protease inhibitors TCA, mirtazapine, paroxetine - weight gain may benefit some patients bupropion, stimulants - may benefit anergic depression The Epidemiology of Major Depressive Disorder Results of National Comorbidity Survey Replication Kessler RC et al. JAMA 2003; 289:3095-3105 Methods: face-to-face household survey; N=9090 Results – Lifetime prevalence of MDD – 12 month prevalence – 12 month comorbidity prevalence = 16.2 % = 6.6 % = 78.5 % Note: 51% of depressed pts had comorbid anxiety disorders – Percent of depressed pts receiving tx – Percent of treated depressed pts receiving adequate tx – Percent of all depressed pts receiving adequate tx = 51.6 % = 41.9 % = 21.7 % FDA Approved Uses of SSRI and Venlafaxine SSRI MDD Fluoxetine X Sertraline X Paroxetine X GAD OCD Social Phobia X X X X X X X X X X X X PMDD X Escitalopram Venlafaxine PTSD X Fluvoxamine Citalopram Panic X X SSRI in the Management of Anxiety Disorders General Treatment Considerations If 1 SSRI is FDA-approved ALL appear to be effective Start low and go slow Onset of tx effect slower for anxiety d/o (vs MDD) Higher doses required for anxiety d/o: OCD, Panic D/O Important considerations in choosing SSRI drug interactions tolerability Relationship of Antidepressant Mechanism to Target Symptoms Does Selectivity Matter ? Theory A: Antidepressants should be tailored to target symptoms Anxious and/or Irritable Anergic and/or Amotivational Severe and/or Melancholic 5HT agents (SSRI) NE/DA agents (bupropion, amantadine, modafinil) 5HT/NE agents (?) (TCA, high-dose venlafax, duloxetine) Theory B: If the antidepressant successfully relieves the depression, all symptoms will resolve regardless of the mechanism. Does Pretreatment Anxiety Predict Response to Either Bupropion SR or Sertraline ? Rush AJ et al. J Affect Dis 2001; 64:81-87 70 60 50 HAMD 40 Response 30 Rate 20 < 13 13-17 18-23 > 23 10 0 Bupropion Sertraline Placebo Baseline HAMA scores ‘Are you more worried or tired ?’ - Owen Wolkowitz M.D. - SSRI preferred in worried patients - Bupropion preferred in tired patients Comparison of Gender Response Rates: Sertraline vs Imipramine Kornstein et al. Am J Psychiatry 2000; 157:1445-1452 70 60 50 62 57 46 45 40 30 20 10 0 women men sertraline imipramine Minimal Response to Antidepressant Treatment Alternatives to SSRI Ensure completion of therapeutic trial (4-6 wks) Ensure optimal dose of antidepressant Partial Response augmentation – Bupropion – Other (lithium, T3, lamotrigine, modafinil, other) Nonresponse – – switch Other SSRI Other antidepressants (SNRI, bupropion, other) Suggestion #4: Optimize Monotherapy (ie – don’t be afraid to dose) Augmentation Strategies and Other Alternatives Bupropion Lithium Thyroid supplementation (T3) Buspirone Pindolol Lamotrigine Stimulants Modafinil Amantadine, Pramipexole Atypical Antipsychotics Other: folic acid, omega 3, inositol, sex hormones, DHEA, SAMe Medication Augmentation after the Failure of SSRIs for Depression Trivedi MH et al (STAR*D). NEJM 2006; 354:1243-1252 Methods – 2876 depressed patients enrolled from 23 psychiatric, 18 primary care settings into rigid treatment protocol – 565 pts failing to achieve remission after 11.9 wks citalopram (55 mg/d) – Pts randomized to bupropion SR (267 mg/d) or buspirone (41 mg/d) Results – Reduction in depressive symptoms (QIDS-SR): bupropion (25.3 %) vs buspirone (17.1 %) p <0.04 – Rates of Remission (QIDS-SR): bupropion (39.0%) vs buspirone (32.9%) ns – Discontinuation due to side effects: bupropion (12.5 %) vs buspirone (20.6%) p < 0.0009 Switching within the SSRI Class Thase M. APA Annual San Francisco 2003 Brown, Harrison (1995) Zarate (1996) Thase (1997) Thase (2001) Thase (2002) Calabrese (2003) Fluox Sert 71 % (79/112) Fluox Sert 42 % (13/31) Sert Fluox 63 % (67/106) Fluox Cital 62 % (35/57) Parox Cital62 % (32/51) Fluox Cital 65 % (36/65) Switching to an SNRI Nelson JC. J Clin Psychiatry 2003; 64 [suppl 1]:5-12 Nierenberg (1994) DeMontigny (1999) Kaplan (2002) Poirer (1999) SSRI Venlafaxine SSRI Venlafaxine SSRI Venlafaxine Various Venlafaxine or Parox 33% (28/84) 58% (88/152) 87 % (63/73) 52 % (32/61) 33 % (20/61) Bupropion-SR, Sertraline or Venlafaxine-XR after the Failure of SSRIs for Depression Rush AJ et al (STAR*D). NEJM 2006; 354:1231-1242 Methods – 2876 depressed patients enrolled from 23 psychiatric, 18 primary care settings into rigid treatment protocol – 727 pts failing to achieve remission or couldn’t tolerate citalopram – Pts randomized to bupropion-SR (283 mg/d), sertraline (135 mg/d) and venlafaxine-XR (194 mg/d) Results – No significant differences between treatments in any primary outcomes – Reduction in depressive symptoms (QIDS-SR): bupropion-SR (16.4 %) vs sertraline (21.9 %) vs venlafaxine-XR (16.9%) – Rates of Remission (QIDS-SR): bupropion-SR (25.5 %) vs sertraline (26.6 %) vs venlafaxine-XR (25.0%) – Discontinuation due to side effects: bupropion-SR (27.2 %) vs sertraline (21.0 %) vs venlafaxine-XR (21.2%) Atypical or 2nd Generation Antipsychotics (SGA) Introduction Empiric Definition: “Atypical Antipsychotics do NOT… – – – induce catalepsy (ie - parkinsonism) increase prolactin upregulate D2 receptors (ie - tardive dyskinesia) Working Definition: “…cause less EPS, TD than conventional agents” Mechanism – Dopamine (D2) plus Serotonin (5HT2a) blockade – D2 blockade in mesolimbic area relieves positive symptoms – 5HT2 blockade in mesocortical area facilitates DA release to relieve negative symptoms (esp cognition) – 5HT2 blockade in nigrostriatum prevents EPS effects 2nd Generation Antipsychotics (SGA) Relative Advantages Safety – – – less extra-pyramidal side effects (EPS) less tardive dyskinesia (TD) less cognitive impairment Efficacy – – – – uniquely effective for tx-resistant schizophrenia more effective vs negative symptoms more effective for cognitive symptoms other indications Bipolar disorder (esp mania) Dementia (?) Depression (?) A Novel Augmentation Strategy for Treating Resistant Major Depression Shelton RC et al. Am J Psychiatry 2001; 158:131-134 Methods: – patients identified with h/o tx-resistance and HAMD > 20 – open label phase consisted of 6 wk escalating dose fluoxetine (20-60 mg/d) – responders were excluded – remainder of patients randomized to 8 week trial of olanzapine plus placebo olanzapine plus fluoxetine fluoxetine plus placebo – N = 28 2nd Generation Antipsychotics (SGA) Relative Disadvantages Safety – – Efficacy – – – – metabolic effects (weight gain, diabetes, hyperlipidemia) other: orthostasis, sedation limited research data in dementia (behavioral disturbances) limited research data in bipolar disorder (maintenance treatment) virtual absence of RCT data in depression inappropriate prescribing (eg – Seroquel for insomnia) Cost !! Weight Gain with Antipsychotic Drugs [Meta-analysis at 10 weeks] adapted from Allison et al. Am J Psychiatry 1999;156:1686-1696 12 10 8.7 lbs 9.1 8 8 6 4.6 4 2.9 2.4 2 -1.6 -0.86 0.1 0 -2 ne pi za lo C e in ap nz la O ne pi tia ue Q e on ri d pe is R ne do in ol o eb ac l tro on C ol id er op al H e on id as pr Zi M Pl Metabolic Effects of 2nd Generation Antipsychotics Consensus Statement – Diabetes Care 2004; 27:596-609 Weight Gain – Increased risk: family hx, underweight, ethnicity – Dose-dependent (?) – Effect plateaus at 24-52 weeks (?) Diabetes – Case reports of DKA with all SGA – Not necessarily associated with weight gain Atherogenic Lipid Profile – triglycerides, LDL, HDL 2nd Generation Antipsychotics (SGA) Monthly Cost of Therapeutic Dose AWP. First Data Bank. Feb 2004 $700 $622 $600 $476 $465 $500 $433 $400 $374 $329 $292 $274 $300 $200 $100 $0 y) da g/ m 0 y) (2 da le g/ zo m ra 5 y) ip (1 da ip e l g/ Ar m zo ra 60 y) ip (1 ip da e Ar g/ on m id 00 as y) 6 ( pr da Zi g/ ne m pi 0 tia y) 2 ( ue da e Q n g/ i m ap 5 nz (1 y) la e da O in g/ ap m (4 nz y) la e da O on g/ m rid 00 pe is (3 R ne pi za lo C Summary Recommendations Target antidepressants to specific populations – Based on comorbidity and target symptoms Ensure adequate trial ( 4 weeks) Optimize Monotherapy ( dose if tolerated) Partial Response (augmentation) – Strong Evidence: – Moderate Evidence – Preliminary Evidence lithium, T3, bupropion buspirone, lamotrigene, modafanil amantadine Nonresponse to SSRI (switch) – Switch to different SSRI (if tolerated) – Switch to other classes: SNRI, bupropion, mirtazapine – 3rd line: TCA, MAOI, SGA (?) Coming Attractions Generics: – sertraline (2006 ?), venlafaxine XR (2008 ?) NK1 or Substance P antagonists (Emend) Selegiline (Emsam) Glucocorticosteroid antagonists (eg - mifepristone, ketoconazole, metyrapone) CRF antagonists* BDNF enhancers * * - denotes product not currently available in United States Transdermal Selegiline (EMSAM) Overview • MOA • Pharmacokinetics • Drug/Dietary Interactions • Nonspecific MAO inhibitor at high doses (eg – MAO-A & MAO-B) • Transdermal delivery results in minimal MAO inhibition in GI tract • Plasma half-life of 18-24 hours • Metabolized via Cyt P450 system (Cyp 2A6, 2B6, 3A4) • Multiple active metabolites (including methamphetamine) • Avoid concurrent administration of SSRI, SNRI, TCA, bupropion, mirtazapine, SJW, sibutramine, tramadol, meperidine, dextromethorphan and cyclobenzaprine • Washout: • • 4 half-lifes after D/C of drugs above 2 weeks after D/C of EMSAM • Low tyramine diet NOT necessary with 6mg patch • Low tyramine diet IS recommended with 9mg and 12mg patches • Adverse Effects • Dosing and Administration • Application site reactions (31% vs 15% with placebo) • Other: dizziness, insomnia, sexual dysfunction • Apply 6mg patch (20mg/cm3) to upper torso every 24 hours