Clinical Trial Designs for RCTs focussing on the Treatment of Agitation in people with Alzheimer s disease Professor Clive Ballard Dr Byron Creese University of Exeter, UK
Guardian guide for 2018: Top 5 UK medical school Penryn ESI
Risperidone Efficacy: BEHAVE-AD Ballard & Howard 2006 Nature Neuroscience Reviews Target symptom Mean Difference from placebo p value 95% CI Risperidone 1mg Psychosis -0.79 p=0.03-1.31 to -0.27 Risperidone 1mg Aggression -0.84 p=0.0002-1.28 to -0.40 Risperidone 2mg Aggression -1.50 p<0.0001-2.05 to -0.95
STAR TRIAL: Zhong et al 2007 Quetpiapine 200mg (N=114) Quetiapine 100mg (N=120) Placebo (N=92) PANSS-EC -5.7 (0.9) -4.9 (0.8) -3.9 (0.9) NS NPI (total) -9.7 (2.2) -8.9 (2.1) -8.2 (2.4) NS Evaluation NPI (agitation) NPI (psychosis) -1.1 (0.5) -0.9 (0.5) -1.2 (0.5) NS -2.5 (0.9) -1.8 (0.8) -2.5 (0.9) NS CGIC 3.0 (0.2) 3.2 (0.2) 3.6 (0.2) NS
Major Adverse Outcomes with antipsychotics over 6-12 weeks (FDA, Schneider et al 2005,Ballard et al 2009) Parkinsonism Sedation Gait disturbance Increased respiratory infections Oedema Accelerated cognitive decline (2-4 fold) Stroke (>3 fold) Other thrombo-embolic events (up to 80%) Mortality (1.5-1.7 fold)
Possible Interpretations Therapies Not good enough Small effect sizes Targets unclear Very heterogenous study populations Challenges with trial design Heterogenous trial populations Low entry thresholds Short duration No non pharmacological interventions doesn t follow best practice How rigorously have underlying medical causes and pain been excluded High placebo response Difficult to interpret major adverse events without a meta-analysis
Longer duration
Change from Baseline to 6 months DART AD Ballard et al PLOS Medicine 2008
DART AD: Differential Survival Ballard et al Lancet Neurology 2009 Differences in the survival rates in the DART-AD trial 80% Survival rate on placebo Survival rate on a antipsychotic 70% 60% 50% 40% 30% 20% 10% 0% 24 36 42 Survival rate on placebo 71% 59% 53% Survival rate on a antipsychotic 46% 30% 26% Number of months The dementia antipsychotic withdrawal trial (DART-AD): long-term follow-up of a randomised placebo-controlled trial. www.thelancet.com/neurology.09 Jan 2009
No Benefit and Accelerated Cognitive Decline with Quetiapine rivastigmine quetiapine placebo ChI v plac Nlp v plac Week 6 N=24 (15 completed SIB) N=26 (14 completed SIB) N=29 (17 completed SIB) Diff CMAI -8.3±18.4-4.7±17.3-6.2±17.2 T=0.4 P=0.67 T=0.3 P=0.74 Diff SIB +4.2±15.4-10.5±14.8 +2.8±15.5 T=0.3 P=0.80 T=2.4 P=0.02* Week 26 N=24 (16 completed SIB) N=26 (15 completed SIB) N=29 (17 completed SIB) Diff SIB -1.1±21.1-11.6±15.6 +2.3±18.1 T=0.5 P=0.61 T=2.3 P=0.03* Diff CMAI -10.5±20.4-4.4±15.7-7.9±16.6 T=0.5 P=0.62 T=0.1 P=0.87 AGIT-AD Ballard et al 2005 BMJ
Novel Statistical Approaches
Dextromethorphan/Quinidine (DM/Q) JAMA 2015 220 patient randomized to Dextromethorphan/Quinidine (DM/Q) or placebo in 10 week trial Complicated 3:4 randomization design with re-randomization of placebo non-responders after 5 weeks 88% completed trial Significant benefits in agitation/aggression and CGIC, with benefits evident from week 1 Falls and diarrhea were the main emergent adverse events (both <10%)
Non-Pharmacological Therapy
WHELD: Key Results Ballard et al Am J psychiatry 2016 AR significantly reduced antipsychotic use by 50% (OR 0.17, 95% CI 0.05 to 0.60, p=0.006). AR and SI significantly reduced mortality (OR=0.36, 95% CI 0.23 to 0.57, p<0.001) Benefits in mortality were achieved without a worsening of neuropsychiatric symptoms in people receiving AR and SI (-0.44, CI - 4.39 to 3.52, p=0.82) EX significantly improved depression (-4.74, CI 0.76 to 8.72) and neuropsychiatric symptoms (-4.01, 95% CI -7.91 to -0.10, p=0.045). SI significantly improved quality of life (6.04, 95% CI 0.24 to 11.84, p=0.042) Combination of both SI and AR (p<0.04) and EX and AR (P<0.02) also significantly improved apathy
Brief Psychosocial Therapy (BPST ) in clinical trials Previous clinical trials of psychosis and behavioural symptoms in Alzheimer s Disease have experienced problems with high placebo response It is important to make sure a new drug is being tested in people who genuinely need it BPST is designed to mirror best practice guidelines and reduce the placebo response by identifying people who improve with a non-drug approach Only people who do not improve following BPST progress to pharmacological treatment In 3 previous trials of psychosis or agitation, has excluded 25% of people in run-in phase, but substantially reduced placebo response -with significant benefits compared to placebo in 2 of the trials (Howard et al 2007, Ballard et al 2009, Cummings et al 2014, Ballard et al 2017) Currently being used in 3 further ongoing clinical trials
How is the BPST delivered? Two - four week intervention to enable enjoyable activities between a person with dementia and their caregiver for 10-15 minute a day Therapist works with a caregiver (care assistant or family member) over four sessions: Training (Day 1): in person (30-45 minutes) Follow-up (regular x 2*): by telephone (15 minutes) Baseline (Day 14-28): in person (15 minutes) Caregiver delivers the BPST to the patient Daily: 10-30 min Completion of a simple diary Follow-up calls support and reinforce the caregiver *Schedules for each person with depend on screening period: Four weeks = weekly follow-up Two weeks = Follow up every 4 days
Discontinuation Design
bettina.husebo@isf.uib.no
bettina.husebo@isf.uib.no
Clear Criteria
Cummings et al 2017: IPA criteria for agitation Patients must meet criteria for cognitive impairment and exhibit behaviours such as excessive activity and verbal or physical aggression severe enough to produce disability in social, or interpersonal functions, or activities of daily living. These symptoms should not be attributable to other psychiatric or medical disorders, suboptimal environment, or drug effects. Future validation studies are needed to confirm or revise the definition. This definition will facilitate clinical trials and other types of clinical and translational research. New IPA Criteria for Agitation in Cognitive Impairment. Available from: https://www.researchgate.net/publication/308775448_new_ipa_crit eria_for_agitation_in_cognitive_impairment [
Modified CGIC
CitAD: JAMA 2014 OBJECTIVE: To evaluate the efficacy of citalopram for agitation in patients with Alzheimer disease. DESIGN, SETTING, AND PARTICIPANTS: CitAD was a randomized, placebo-controlled, double-blind, parallel group trial with 186 patients with probable AD and clinically significant agitation INTERVENTIONS: Patients were randomized to receive a psychosocial intervention plus either citalopram (n = 94) or placebo (n = 92) for 9 weeks. Dosage began at 10 mg per day with planned titration to 30 mg per day over 3 weeks based on response and tolerability.
CitAD: Results MAIN OUTCOMES AND MEASURES: The NBRS-A estimated treatment difference (citalopram minus placebo) was -0.93 (95% CI, -1.80 to -0.06), P =.04. CGIC showed 40% of citalopram participants having moderate or marked improvement from baseline compared with 26% of placebo recipients, with estimated treatment effect (odds ratio [OR] of being at or better than a given CGIC category) of 2.13 (95% CI, 1.23-3.69), P =.01 (Cohen s d standardized effect size 0.36). Participants who received citalopram showed significant improvement on the CMAI, total NPI, and caregiver distress scores but not on the NPI agitation subscale, Worsening of cognition (-1.05 points; 95% CI, -1.97 to -0.13; P =.03) and QT interval prolongation (18.1 ms; 95% CI, 6.1-30.1; P =.01) were seen in the citalopram group.
Central Rating
-020 Study: Pimavanserin Demonstrated Highly Significant Antipsychotic Efficacy (Lancet Feb 2014) 26 SAPS-PD (primary endpoint) (ITT, N=185; change from baseline) * **
SAPS-PD Score and Change from Baseline Subgroup Analysis (OC) (ITT Analysis Set) Subgroup: Screening MMSE < 25 Change from Baseline to Day 43 Placebo Pimavanserin N 19 27 Mean (SE) -0.47 (1.89) -7.11 (1.81) Median 2.00-8.00
Improved trial design Clearer definition of agitation (and sub-syndromes) Non-pharmacological interventions to reduce placebo response Central rating of primary outcome to reduce impact of inter-rater variability New CGIC for neuropsychiatric symptoms Novel statistical approaches Discontinuation element to establish continued benefit Higher threshold for study entry Longer duration of trial (particularly for adverse events) Better targets (syndrome definition, molecular targets)
Contacts Clive Ballard: c.ballard@exeter.ac.uk Byron Creese: b.creese@exeter.ac.uk