A Study to Evaluate the Use of an Indwelling Catheter to Obtain Cerebrospinal Fluid (CSF) by Low-rate Continuous Sampling (MK-0000-211)

Study Overview
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Brief Summary
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This is a study to evaluate the feasibility and tolerability of low-rate continuous Cerebrospinal Fluid (CSF) sampling and to estimate the number of participants who exhibit severe baseline instability of CSF amyloid beta isoform Aß40 concentrations in healthy participants.

Official Title
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A Clinical Study to Evaluate a Modified Serial CSF Sampling Method by Indwelling Lumbar Catheter in Healthy Volunteers

Conditions
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Alzheimer's Disease

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Must be in good health Must have a body mass index greater than or equal to 18 kg/m^2 and less than or equal to 30 kg/m^2 Exclusion Criteria: Is pregnant, nursing, or plans to become pregnant Has clinically significant cardiovascular, renal, hepatic, gastrointestinal (GI), neurological, endocrine, hematological, dermatological or metabolic disease, or clinically significant abnormalities, as determined by medical history, physical examination, electrocardiogram, vital signs, or laboratory tests Has a history of migraine headaches Has a history of recent lumbar CSF sampling within 3 weeks prior to screening, history of lumbar spine surgery, or chronic low back pain or injury Has an infection or inflammation of the skin in or in close proximity to the area of the lumbar puncture site Has a history of a seizure disorder Is noted to have papilledema or clinically significant focal neurological deficits at the screening physical examination, as well as abnormalities of CSF pressure on initial testing once access to the lumbar space is achieved Has absolute or relative anatomic abnormalities that would be a contraindication to lumbar puncture Is a heavy consumer of alcohol Has used nicotine in the past 6 months Has a history of a significant psychiatric disorder

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Continuous drip sampling<br>Sampling at  0.6 cc / hour ( 1.2 cc / 2 hours, or lowest feasible rate given technical requirements and volume requirements for core analytes assays) | |
| Intermittent sampling<br>Sampling at 4 cc every 2 hours (+ 2 cc dead space clearance, total = 6 cc / 2 hours) | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Increase in CSF Aβ40 levels as measured by the new low flow continuous drip sampling method |  | Up to 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Increase in CSF Aβ40 levels as measured by the current intermittent drip sampling method |  | Up to 24 hours |