glucose sensors cwd

8/3/2019 Glucose Sensors CWD

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Glucose Monitorsand Glucose

Sensing

Applications for the21st Century and Beyond

The Quest for the Closed Loop


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WhyGlucose Sensing??

More real time assessment

Ability to detecthypoglycemia andhyperglycemia atodd times

Better administration and correlation of insulindosagesless guessing

Mayuncover eating disorders and other issuesrelated to stress, diet and exercise

Patient compliance with monitoring an issue manydo not like to poke fingers or other sites so often.Pain and discomfort, lack of blood obtained, loststrips, etc.


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WhyGlucose Sensing??

Goal Closing the Loop

An artificialpancreas

Provide accurate and specific data to control glucoselevels many individuals keep blood glucoses higherthan optimal to avoidhypoglycemia

Fear ofhypoglycemia in the middle of the night notwaking up

Take the worry out of diabetes treatment Type 1patients in particular; parents, children andphysicians


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Optimal Conditions for GlucoseMeasurement

Immediate availabilityof results andmeasurements

High frequencyof measurements Measurements every2-5 minutes would be ideal

Ability to detect rapid rise or decline is necessity

Need quick signal stabilityafter initiation or

placement Stabilityoverprolongedperiod of time (>3

days necessary)


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Case for Glucose Sensing Recent

Studies

23 patients participated hospitalized andambulatory

Both Type 1 and Type 2 individuals Study lasted 72hours (key time limit)

75 capillarysamples were obtained

Microdialysis subcutaneous monitoring system used

microdialysis catheter; extracorporeal electrochemicalsensor

signal needed to be corrected for fluid transportation 31minutes (lag time)

Diabetes Care 24: 1696, 2001 Jungheim et al


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Results of Studyand Conclusions

Studies showed no limitations to patients activityandonlymild skin irritation

Difference between SCGM and capillaryglucose was~ 7-9 % over the full range (meter differences can beas much as 10 15 %)

Hypoglycemia was detected with SCGM but wasmissed 58-71% of the time byspot capillary

measurements. This despite 5-7 or moremeasurements per day

No decay in sensitivityover the 72hourperiod

SCGM could be useful in glucose control & therapy


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Glucose Monitor Development

Race for the Closed LoopSystem, Painless,

Continuous and the Gold


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Types of Monitors in Development

Minimally invasive interstitial devices

Transcutaneous optical devices

Electrochemical sensing devices

subcutaneous

Implantable

Implantable optical sensors


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Physiologyof Interstitial Fluid

Extracellular fluid and flows through thecapillarywalls

Glucose levels in interstitial fluid bloodglucose

Lag time could be ~ 10 to 20 minutes

Perspiration, oils and other environmental

factors (lotions, etc.) can dilute themeasurements and adverselyaffect theresults as sample size is small


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Interstitial Glucose Sensor

Glucowatch Biographer 2

Cygnus Corp: www.glucowatch.com


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Glucowatch Schematic


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Advantages and Limitations ofGlucowatch System

Non-invasive

Detects trends andpatternsin glucose levels

readings every10 minuteswith up to 6/hour = 72readings/monitoring session

Alertspatients to rapidschanges in glucose levels

Lesspainful??

Computer download capable ? Abilityto determine insulin

or medication adjustmens

2hour warm-up period

Calibration is needed witheach sensor use

Skin irritation with sensorand adhesive

Skipped readings possiblewith rapid changes intemperature,perspirationand if system is bumped or

dislodged If several readings in a row

are skipped, the systemmust be recalibrated

Advantages Limitations


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Use of Glucowatch Biographer 2

Intended for use in adults and children todetect trends andpatterns in glucose levels

To detect and assess hyperglycemic andhypoglycemicpatterns to help facilitateadjustments in therapy

To be used as an adjunctive device, tosupplement, not replace, information obtainedfrom traditional and standardhome glucosemonitoring devices!


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Glucowatch Biographer 2

Draws out interstitial fluid byreverse electroionophesis

Glucose interacts with Glucose Oxidase Membrane to formhydrogenperoxide which interacts with biosensorproducing low

electric current which is measured and analyzed Glucowatch 2

Cost $599 to $799

Rebates can save $200 to $300

Auto sensor

Disposable transdermalpad

Changed every14-15hours

~$4 each (2 needed) for each recording session

Concerns with calibration time, risk of infection and irritation


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Glucose Collection with the GlucoWatchG2Biographer Uses Reverse Iontophoresis

Only small compounds pass

through the skin.

No proteins (e.g., hemoglobin)in the extract

Glucose is collected at thecathode.

Interfering species (ascorbateand urate) collected at anode

The charge and size

exclusion properties ofreverse iontophoretic

extraction will lead to a very

clean sample.Cl-, (ascorbate, urate)

Na+, neutral species(i.e., glucose)

CATHODECATHODE ANODEANODE

Data on file, Cygnus Inc. 2002.


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The Automatic Monitoring Processwith the GlucoWatchG2 Biographer *

3 min glucose collection 7 min glucose measurement

107107mg/dLmg/dL

* Following a 2 hour warm-up and calibration

A RUNNING AVERAGE PROVIDES READINGS EVERY 10 MINUTESA RUNNING AVERAGE PROVIDES READINGS EVERY 10 MINUTES

InternalInternalmeasuremeasure

DisplayedDisplayedreadingreading

3 min3 min 7 min7 min 3 min3 min 7 min7 min 3 min3 min 7 min7 min 3 min3 min 7 min7 min

105105mg/dLmg/dL118118mg/dLmg/dL

127127mg/dLmg/dL

109109mg/dLmg/dL

101101mg/dLmg/dL

112112mg/dLmg/dL

3:10 pm3:10 pm 3:20 pm3:20 pm 3:30 pm3:30 pm 3:40 pm3:40 pmTIMETIME

Data on file, Cygnus Inc. 2002.


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0

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0 100 200 300 400

One Touch Profile

BiographerReadings(mg/d

L)

E

D

B

B

E

C

A

C

D

2996 paired pointsSlope = 0.95, Intercept = 12.6 mg/dL, r = 0.80

GlucoWatchBiographerHome Study Clarke Error Grid Analysis

One TouchProfile* Glucose Readings (mg/dL)

ZONE

A

B

C

D

E

Biographer

Readings

60%

34%

1%

4%

0.1%

(A) Accurate. Biographer within 20% of finger-sticktest result (or both below 70 mg/dL)

(B) Acceptable. Difference greater than 20% butBiographer would not lead to baddecision

(C) Might cause an over-correction of normalglucose levels. Finger-stick blood glucose test

result in the normal range, but Biographer reading ishigh or low.

(D) Failure to detect a high or low glucose level.

Biographer reading in the normal range, but finger-

stick blood glucose test result is high or low

(E) Treatment error could occur. Biographerreading low when finger-stick blood glucose is high

or Biographer reading high when finger-stick is low.

Data on file, Cygnus Inc. 2002.* One TouchProfile Johnson andJohnson, New Brunswick New Jersey


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Studies of Glucowatch vs. Meters

Differences between interstitial fluid and bloodglucose

Time lag: 17.2 minutes 7 minutes with Glucowatch

Time lag: 13 minutes with most blood glucose meters

With glucose increasing, changes were less asmeasured byGlucowatch as compared with blood

With glucose decreasing, changes were greater as

measured byGlucowatch as compared with blood ormeters

Conclusion: possible false hyperglycemia and falsehypoglycemia if taken unilaterally

Kulcu et al:

ADA Meeting2002


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SpectRx Glucose Sensing System

Transdermal Biophotonic System

Fluid is collected through micropores

Laser system used on the outer layer of skin Measured in a patch which contains a glucose sensor

Clinical trials are ongoing

Is not FDA approved at this time

Still similar to Glucowatch in that itprovidesinformation on trends and not necessarily real-timefor treatment adjustments

SpectRx website: www.spectrx.com


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SpectRx Glucose Sensing System

Laserdevice on the skin surface

Patch with sensor system embedded

www.spectrx.com


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Preliminarydata with SpectRx ISFSystem

www.spectrx.com


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Preliminarydata with SpectRx ISFSystem


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Pendragon Glucose Sensing System

Uses electromagneticwaves

Attached to lowerforearm similar to theGlucowatch

Performsmeasurements every

minute but averagingoccurs


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Pendragon Glucose Sensing System


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Recent Studywith PENDRA

15 individuals without diabetes

Changes in microcirculation of the arms resulted invarying glucose values

Temperature changes, other environmental issueshad to address via a complex calibration procedure

Conclusions: Need to fix device appropriately to arm to avoid

possible variations Needs extensive physician and patient training to

operate

Needs further studies prior to any extensive use in theclinical setting

Diabetes Technologyand Therapeutics 6:435, 2004


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Electrochemical Glucose Sensors

CGMS

TGMS

DexC

O

M


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Continuous Glucose MonitoringSystem--CGMS

Basic Premise: Glucose + Oxygen = Gluconic Acid +H2O2

Reaction is submitted to an electrical current which isproportional to the glucose concentration which is

measured

Enzymatic or Electrochemical Sensors are implantedin the subcutaneous tissue (under the skin)

Similar to the catheters used in insulin pump therapy

Short term use atpresent; reliability just 48 to 72hours


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Medtronic (MiniMed) CGMS System

Two Views of CGMS


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Mechanism of Action of CGMS

Enzymatic Reaction is measured by sensor in IF through skin


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CGMS System

Sensor is percutaneous an ~1mm in diameter

Measures an average glucose value every5minutes and is stored in the monitor

Hard wired system; worn externally

Requires calibration at 4-5 times per day, otherwisedata is not able to be downloaded

Able to enter events on the monitor to assist withinterpretation of results

3 dayuse onlyat this time Not real timerequires return to physician office for

download and interpretation


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CGMS System

Problems with encapsulation tissue which can causeerrors in data collection

Anything implanted in the bodyover time becomes

covered with a protein layer initially and then a collagenlike layer

Encapsulation tissue is to protect the body from foreignobjects which maybe perceived as harmful and to isolatethe object chemically (ie.broken port in pulmonary

artery) This chemical isolation could decrease the sensitivityand

response time of electrochemical subcutaneous systemssuch as CGMS


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CGMSCGMS ReproducibilityStudyReproducibilityStudyMetzger, M. et al: Diabetes Care 25:1185, July2002Metzger, M. et al: Diabetes Care 25:1185, July2002

Self monitoring of glucosesSelf monitoring of glucosesseveral times per day will leaveseveral times per day will leavegapsgaps large excursions canlarge excursions canoccur without patientoccur without patientknowledgeknowledge

Hypothesis:Hypothesis: to test theto test thereproducibility of the CGMS inreproducibility of the CGMS inrealreal--life settinglife setting

CGMS may be a tool that couldCGMS may be a tool that could

alleviate this difficultyalleviate this difficulty System measures glucoseSystem measures glucose

concentration every 5 minutesconcentration every 5 minutesfor a 72 hour periodfor a 72 hour period

Preliminary StudyPreliminary Study performedperformedin Type 2 patientsin Type 2 patients

~ 150 separate glucose tracings~ 150 separate glucose tracings

Included healthy volunteers andIncluded healthy volunteers andpatients on only metforminpatients on only metformin

Correlated with frequent bloodCorrelated with frequent bloodglucose measurementsglucose measurements

Noted exceeding high incidenceNoted exceeding high incidenceof hypoglycemic events with noof hypoglycemic events with nosymptoms andsymptoms and notnot confirmed byconfirmed bysimultaneous blood glucosesimultaneous blood glucosemeasurementsmeasurements

Correlation coefficientCorrelation coefficient r=0.74r=0.74


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Real Life Study was undertaken to determine accuracyReal Life Study was undertaken to determine accuracy

and reproducibility of tracings utilizing the CGMS deviceand reproducibility of tracings utilizing the CGMS device

11 patients involved in the study11 patients involved in the study 6 had Type 1 diabetes6 had Type 1 diabetes

3 had Type 2 diabetes3 had Type 2 diabetes

2 healthy volunteers with no history of DM2 healthy volunteers with no history of DM

10 male, 1 female10 male, 1 female Placed on two glucose sensor devices simultaneously for aPlaced on two glucose sensor devices simultaneously for a

3 day period with usual normal activity3 day period with usual normal activity


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ProtocolProtocol Sensors were attached according to theSensors were attached according to themanufacturers instructionsmanufacturers instructions

Sensors were placed in the abdominal SQ tissue 4Sensors were placed in the abdominal SQ tissue 4--5 cm to5 cm to

the right or left of the umbilicusthe right or left of the umbilicus

Calibration and Initialization were performed and 1 hourCalibration and Initialization were performed and 1 hourwas elapsed before first capillary glucosewas elapsed before first capillary glucose

Meal times were recordedMeal times were recorded

Capillary glucoses were done immediately post meals,Capillary glucoses were done immediately post meals,during the night and early AMduring the night and early AM

Capillary glucoses were entered into the monitor within 5Capillary glucoses were entered into the monitor within 5minutes of determinationminutes of determination


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CGMSCGMS ReproducibilityStudyReproducibilityStudyMetzger, M. et al: Diabetes Care 25:1185, July2002EAMetzger, M. et al: Diabetes Care 25:1185, July2002EA

Download was done upon completion and analysis wasDownload was done upon completion and analysis wasperformed immediatelyperformed immediately

Anonymity was preservedAnonymity was preserved

Each day was divided into 8 time intervals according toEach day was divided into 8 time intervals according tothe meal times of the patientthe meal times of the patient

Classifications:Classifications:

A:A: SatisfactorySatisfactory

B:B: if all glucose values are between 80if all glucose values are between 80 150150 C:C: glucose > 150 during >1 hr., too lowglucose > 150 during >1 hr., too low

D:D: glucose < 70 during >30 minutes or impossible to evaluate dueglucose < 70 during >30 minutes or impossible to evaluate dueto technical reasonsto technical reasons


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D Classification was further subclassified:D Classification was further subclassified:

D1:D1:Low concordance between sensor and glucometer r < 0.8 orLow concordance between sensor and glucometer r < 0.8 or

the difference is too high (28%)the difference is too high (28%)

D2:D2:Insufficient number of meter glucose values entered forInsufficient number of meter glucose values entered for

calibrationcalibration

D3:D3: Strong midnight shift: usual sensor glucose values postStrong midnight shift: usual sensor glucose values post

midnight. Usually secondary to insufficient number of calibrationmidnight. Usually secondary to insufficient number of calibration

values.values.

Evaluations were analyzed by two different observersEvaluations were analyzed by two different observers

independently and concordance rates wereindependently and concordance rates were

determineddetermined


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CGMSCGMS ReproducibilityStudyReproducibilityStudy

Metzger, M. et al: Diabetes Care 25:1185, July2002Metzger, M. et al: Diabetes Care 25:1185, July2002

MeanMean sensor not recording glucose valuessensor not recording glucose values 46 classified in the D group and not46 classified in the D group and not use of sensor: 60.4use of sensor: 60.4 16.916.9

hours each patienthours each patient

432 single time intervals were initially evaluated432 single time intervals were initially evaluated 78 (18%) were discarded for technical reasons78 (18%) were discarded for technical reasons

32 due to interpretable32 due to interpretable

139 paired sets of data were available for sensor139 paired sets of data were available for sensor--sensorsensorcomparison.comparison.

92 from Type 1 patients92 from Type 1 patients

30 from Type 2 patients30 from Type 2 patients

17 from non17 from non--diabetes volunteersdiabetes volunteers


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Concordance was seen in only 65% of the timeConcordance was seen in only 65% of the timeperiodsperiods

25% noted glucose levels too high in one sensor25% noted glucose levels too high in one sensor

and satisfactory in the otherand satisfactory in the other 9% noted glucose levels too low with satisfactory9% noted glucose levels too low with satisfactory

levels in the otherlevels in the other

1 case noted: sensor 1 showed hyperglycemia,1 case noted: sensor 1 showed hyperglycemia,

sensor 2 showed hypoglycemiasensor 2 showed hypoglycemia No difference between patients with DM and nonNo difference between patients with DM and non

DMDM


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Conclusions:Conclusions:

Accuracy and reproducibility is lower thanAccuracy and reproducibility is lower than

previously thoughtpreviously thoughtDifferences were greatest between the 125 andDifferences were greatest between the 125 and

225 mg/dl range225 mg/dl range most important area inmost important area intreatment of patients with diabetes mellitustreatment of patients with diabetes mellitus

Correlation between two simultaneous sensorsCorrelation between two simultaneous sensorswas lower than that of capillary vs. sensor (r =was lower than that of capillary vs. sensor (r =0.84 vs. 0.90)0.84 vs. 0.90)


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Conclusions:Conclusions:

35% clinically important discrepancies between35% clinically important discrepancies between

two simultaneous sensor tracingstwo simultaneous sensor tracings

Could result in incorrect clinical advice in 17%Could result in incorrect clinical advice in 17%

of patient casesof patient cases

@@

RESULTS OBTAINED IN REAL LIFERESULTS OBTAINED IN REAL LIFESITUATIONS MUST BE INTERPRETED INSITUATIONS MUST BE INTERPRETED IN

INDIVIDUAL CLINICAL TERMSINDIVIDUAL CLINICAL TERMS


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Development of a reliable device for continuousDevelopment of a reliable device for continuous

glucose monitoring is of outmost importance inglucose monitoring is of outmost importance in

the treatment of diabetesthe treatment of diabetes Future endeavors in this area must be rigorouslyFuture endeavors in this area must be rigorously

evaluated in real life situations before releaseevaluated in real life situations before release

to the general publicto the general public

Rebuttal from MedtronicRebuttal from Medtronic concerns in the aboveconcerns in the above

study: software used was earlier version, devicestudy: software used was earlier version, device

was used for more than planned or approvedwas used for more than planned or approved


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Additional StudiesAdditional Studies----20032003

Armstrong and King: ADA Meeting 2003

11 subjects: 2 No Diabetes, 6 Type 1, 3 Type 2

Measured Glucoses with 1 Touch Ultra 7 times per day Wore 2 sensors (CGMS) concurrently for 3 days

Mean Sensor life: 67 hours

Used updated software

Found accuracy with newer software ~94% Most of differences between modalities within 10%

Sensor-sensor differences less than previous study


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Rebuttal to Metzger FindingsRebuttal to Metzger Findings

Expectations did not coincide with CGMS intended use

Study did not use Clarke error grid but was one ofsubjective assessment

Study did use updated software (Solutions 3.0)

Results are similar to those reported in the post-marketing studies (Diabetes Technology andTherapeutics, 2000)

CGMS is intended to supplement, not replace, bloodglucose information using standard monitoring devices

CGMS, when used with home monitoring devices andHbA1C values can help optimize clinical management

Mastrototaro and Gross; Diabetes Care 26:256 2003


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Solutions 3.0 software resolves most of the 18% rate of

technical problems encountered in the study

Correction of the midnight shiftImprovement in the accuracy and reproducibility of

the downloads

Improvement in the agreement between sensor and

meter values

Mastrototaro and Gross; Diabetes Care 26:256 2003


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CONCLUSIONS:

Results should be weighed against the

encouraging results and conclusions fromprevious and evolving reports and research

Appears that this is a work in progress andshould not be utilized as the sole clinical

indicator! should not be used at present as theonly source for change in treatment regimens

-Speakers judgment after reviewing literature


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Sample CGMS Reports

Daily Report of Blood Glucoses


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Sample CGMS Reports

Modal Time Reports Can be varied individually


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Sample CGMS Reports

Composite 3 day report for comparison


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Additional Studies Involving Children

Accuracyof Glucowatch 2 system and CGMS indetectinghypoglycemia

Multi-center study

Involved the Children in Diabetes ResearchNetwork

91 children enrolled

Ages 3-17

Patients were enrolled in a CRC-clinical researchcenter for 24 hours

Diabetes Care 27:722-726 2004


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Glucowatch 2 vs. CGMS

Patients used CGMS and Glucowatch 2 during eachadmission

1/3 patients started CGMS 48hours prior toadmission

1/3 patients started CGMS 24 hours prior toadmission

1/3 patients started CGMS on the dayof admission

Eachpatient used 2 sensors for the G-watch 2 duringthe study 2hour overlap

1 TouchUltra meter used as calibration and control


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Samples: everyhour during the dayevery30 minutes during the night

Hypoglycemia induction test: samples obtained every5 minutes for 90 minutes

Adjustment of values for lag time: time involved insampling the interstitial fluid measuring glucose ascompared with blood

Glucowatch 2 Biographer 17.5 minutes

CGMS 2.5 minutes


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Glucowatch 2

Biographer

~ 23 % of valueswere withinreference rangewhen glucoses were< 60 mg%

51% false alarmswere detected withuse

CGMSSystem

Both modified and

original sensorsnoted < 50%detection withinreference range (36and 48 %)

58% to 60% falsealarms weredetected with use

Results of Study


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StudyConclusions

Neither Glucowatch 2 nor CGMS is accurate in reportingglucose values in the hypoglycemic range

Accuracyof both devices is better when reference glucose

levels are >100 mg/dl

Neither device is appropriate at this time for real timedetection

Both systems are more likely to be of value in adjusting

bolus and basal insulin doses in patients with consistentlyelevated glucoses and A1C levels

The accuracyof these earlygeneration sensors is similarto the earlygeneration meters (circa 1970s-early 1980s)

M difi d H U f CGMS


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Modified Home Use of CGMSGuardian System


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Guardian Home System

Sensor can be set to alarm at certain levels bothhigh and low

Monitor can be placed up to 6 feet away; does not

have to be worn Monitor can store up to 21 days of data

Can be downloaded to personal computer

Still needs calibration similar to CGMS system

Alerts or alarms need to be verified with finger stickglucose

Cost is not set atpresent (~ $800- $1500 anticipated)


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Anticipated Sample Guardian Report

www.minimed.com

Reports similar to CGMSSystem


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Paradigm 522 System PatientUse

Consists of Glucose Sensor, Radio Transmitter andPump receiver

Abstractpresented at ADA 2004 (Orlando)

9 Patients involved; Ages 10-21, Type 1 DM

Used CSII

Did 4 Blood Glucoses/dayvia HGM

Wore 7 sensors during the 3 week trial

A1C levels decreased 0.3% Glucoses decreased average 20 mg%

Work in progress; Not available yet!!!


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Implantable Subcutaneous Systems

Enzyme electrode system

Electrochemical device


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DexCom Subcutaneous Sensor System

Implantable Sensordevice Pager monitoring system


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DexCom Subcutaneous Sensor System

Special bioprotective layerprevents foreign bodyreaction with sensor

Can measure glucoses ranging from 40 mg/dl to700 mg/dl (2.2-38.9 mmol/L)

Recalibration every20 days

160 180 day lifespan for sensor

Still need to do HGM 2-3 times/day to initiateglucose algorithm

Easily implanted in subcutaneous tissue

Can be accomplished as outpatientprocedure

Diabetes Care 27:734, 2004EndocrinologyClinics NA 33:175, 2004


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Therasense Navigator System

Interstitial System Wireless system Needs calibration 1-2

times per day Readings every1-2

minutes conceptualized High and low glucose

alarms to be

incorporated Currentlyexperimental Companynot

distributing info at thistime


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Near Infrared Spectroscopy

Non-invasive techniques


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Sensys Medical Systems

EndocrinologyClinics ofNA 33: 163-173 2004


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Sensys Medical Systems

Measures glucose non-invasively via NIRspectroscopy

Device weighs less than 1.5pounds

Fiber-optichead secured to the forearm Still needs HGM for calibration

Various components such as sweat, fat, etc. caninterfere with efficacy

Can use either volar or dorsal aspects of the forearm Uses a rechargeable battery

Studies ongoing withpatient use


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Open-flow Microperfusion Systems

ADICOL Project-Disetronic/Roche

Advanced Insulin Infusion with aControl Loop


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ADICOL Project Disetronic /Roche

Inserted into thesubcutaneous adiposetissue

Double lumen catheter

Acquires glucosereadings every30minutes

Goal subcutaneousglucose sensing/insulindeliverysystem


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ADICOL Project Disetronic /Roche

Large bore catheter

Readings only

every 30 minutes

Small study sample

with patient use


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Infrared Spectroscopy

Animas CorporationContinuous GlucoseMonitoring System


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Infrared Spectroscopy

Infrared light is absorbed bymolecules

Each molecule has its own spectra (absorptioncharacteristic)similar to its own footprint

Theoretically-bymeasuring the absorbed light vs.wavelength, one could delineate the species andconcentration

In reality this is difficult

Water absorbs most IR light

Blood scatters light

Different species overlap in their spectra or footprint


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Sketch of Animas Sensor


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ImplantedExtravascular Sensor Head


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Early Animas Sensor Head


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C l i ( 2 94) b i l


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0

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Concentration (mg/dl)Determined by Glucometer

C

oncentr

ation(m

g/dl),

usin

g

O

pticalM

ean

Correlation (r2=.94) between optical

and conventional means (500 people)

I i M t i D


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0

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Time

Glu

coseConcentration(mg/dl)

In vivo Measurements in Dog:

Glucometer and Sensor Head vs. Time

Glucometer

Sensor

A i C i S


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Animas Continuous System

Has designed and built short term prototype anddemonstrated stability in animals

Need to miniaturize system Laser diodes under development

Telemetry developed

Electronics being modified and mostlydeveloped

Clinical trials in humans projected to start 2005 or

2006. Projected as earlyPhase 2 studies withsites to be determined. No pediatricpatients tobe involved!

Advantages of


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Advantages of

Animas Monitor

y Provides continuous reading of blood glucose withoutpatient intervention

y Measures glucose in bloodas opposed to some other body

fluid, e.g. interstitial fluid, ocular fluid

y The encapsulation/ fibrin tissue has no effect on monitoraccuracy

y Provides direct access to blood, obviating loss and

interference associated with light transmission through

intervening tissues.

y Sensor stays implanted for at least 5 years, limited by

battery life. No percutaneous wires or cables are utilized.

What is the Goal of These


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What is the Goal of TheseTechnologies?

Development of a ClosedLoop System TheArtificial Pancreas

*Put the Endocrinologist intoEarlyor PermanentRetirement

Have We Achieved


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Have We Achieved

Goal???

Not Yet!!

Wh t H B A li h d?


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What Has Been Accomplished?

New Technology to determine patterns and facilitatechanges in therapy

Prototypes for long term glucose monitoring

More awareness bypatients and families regardingthe importance of intensive therapyand tight controlof blood glucoses

Consumer driven research for an artificialpancreas

More physicians are implementing intensive therapywith technology now available to compliment thetreatment

Fi l Th ht


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Final Thoughts

No system atpresent is appropriate for a closed loopsystem

No system developed atpresent can replace the

finger stick monitor for real time glucose valuesand treatment decisions

Presently, there are 50+ companies or individualsattempting to develop a continuous glucosemonitoring system

EVENTUALLY, THAT DAYWILLARRIVE!!WHEN, ONEONLYKNOWS!

glucose sensors cwd

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