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Alzheimer ’ s Drug Therapy Initiative: Seniors Medication Study (SMS). Ging-Yuek Robin Hsiung, MD MHSc FRCPC FACP Assistant Professor Division of Neurology, Dept. of Med, Malcolm Maclure, ScD, Professor Dept. Anesthesiology, Pharmacology & Therapeutics University of British Columbia.
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Alzheimer’s Drug Therapy Initiative: Seniors Medication Study (SMS) Ging-Yuek Robin Hsiung, MD MHSc FRCPC FACP Assistant Professor Division of Neurology, Dept. of Med, Malcolm Maclure, ScD, Professor Dept. Anesthesiology, Pharmacology & Therapeutics University of British Columbia
Disclosure Dr. Hsiung have received research support from Baxter, Bristol-Myers-Squibbs, Elan, Janssen-AI, Pfizer, Hoffman-La Roche, and Genentech as an Alzheimer clinical trial centre at UBC None of the medications discussed today are related to any of the clinical trials sponsored by the above
Drug Payer Policy: Coverage with Evidence Development “In April 2005, the Centers for Medicare and Medicaid Services (CMS) posted on its Web site a draft guidance document describing a new approach to coverage policy called Coverage with Evidence Development (CED). CED offers an option for coverage of promising drugs, biologics, devices, diagnostics, and procedures that would not otherwise meet Medicare’s evidentiary standards for being ‘reasonable and necessary’. ”
Alzheimer’s Drug Therapy Initiative “Provides eligible B.C. residents with PharmaCare coverage of medications used in the treatment of Alzheimer’s disease while gathering evidence on their effectiveness.”
Continuing users 30,000 Positive Response Original RCT Trial Design of SMS: Continuing vs. Stopping vs. Switching Unwilling Existing AD, new users Continue 3000 10,000 1,000 Indeterminate Response 10,000 Stop Dx 6 mo Randomization Initial Estimated N of 3000 1,000 3000 10,000 New AD cases Switch Stoppers due to intolerance 12,000 1,000 Non-Response 3000 2,000
Seniors Medication Study – stumbling blocks page 1 • No incentives for patients or their doctors to participate in trial. Coverage available to all who fit clinical criteria. • One ethics committee argued it would be coercivefor PharmaCare to limit coverage of drug costs to patients who agreed to be in the trial. • Another ethics committee judged it unethical to do a small trial that had insufficient power to rule out a small but clinically important effect. A drug plan might interpret an inadequately powered study that is ‘not significant’ as meaning ‘evidence of no effect’.
Seniors Medication Study – stumbling blocks page 2 • We took 1 year to develop and test tools and protocol for randomization in busy general practictioners’ office • BC Medical Association opposed Special Authority form without financial compensation • Only a few patients were randomized after 12 months. • A Medical Services Plan billing code was created: fees for referrals and Clock Drawing Tests. These had only a small impact on randomization, but increased enrolment into the plan. • Fair Pharmacare is not “free”, but based on income tax • SMS became an observational cohort study with validation/reproducibility study of Standardized Mini-Mental State Exam and various scales.
Current Observational Study (SMS) Positive Response Continue Eligible AD cases Initiation of treatment to one of three ChEIs (doctor & patient choice) Indeterminate Response Doctor & Patient Choice 6 mo Stop N ~ 200 Non-Response Switch
Seniors Medication Study (n~200) Start of Coverage6 mo12 mo18 mo SMMSESMMSESMMSESMMSE (10-26) OPAR & GDS OPAR & GDS OPAR & GDS GDS Clock* Clock* Clock* TICS* TICS** TICS** *Clock Drawing Test **Telephone Interview of Cognitive Status SMMSE = standardized Mini Mental State Examination OPAR = Overall Patient Assessment Rating GDS = Global Deterioration Scale
SMMSE vs TICS (6 mon) SMMSE Low SMMSE means low TICS (i.e. good negative predictive value) Correlation = 0.59 TICS
Correlation of SMMSE with Components of the Telephone Interview of Cognitive Status (TICS)
SMMSE vs Clock Drawing Test SMMSE Correlation = 0.58 Clock Drawing Test
Clock Drawing Test vs. TICS Clock Drawing Test Correlation = 0.57 TICS
SMMSE vs GDS: low correlation 5 GDS 4 Correlation = - 0.22 SMMSE
TICS vs GDS: low correlation GDS Correlation = - 0.18 TICS
Clock Test vs GDS: low correlation GDS Correlation = - 0.15 Clock Drawing Test
Correlations among measures SMMSE TICS 0.59 n = 111 n = 122 0.58 0.57 - 0.22 - 0.18 Clock Drawing GDS - 0.15 n = 74 n = 122
Lessons learned RCT in “phase 4” setting is not feasible – but can do observational study for effectiveness analysis Limited data collection in real life doctor’s office – can only be a brief test; need to compromise between efficiency & comprehensiveness Clock Drawing Tests conducted by GPs, faxed to researchers for scoring, enabled patients to be assessed without confounding by financial incentives or telephone/hearing problems. Good correlation between SMMSE & TICS, SMMSE & CDT, CDT vs TICS, (validate use of SMMSE in doctor’s office setting) Low correlation between GDS vs TICS, and GDS vs CDT: the test measure different domain – Functional vs Cognitive Limitation of using SMMSE only as the criterion for eligibility for drug funding and outcome measure
Further Studies Await long term outcome (12 & 18 months) of the study Compare trajectory of changes in each outcome measure by different ChEIs SMMSE can be applied in real life with good validity, but limited domains Will need to include multiple eligibility criteria (SMMSE, CDT, GDS) and multiple outcome measurements