Diabetic NeuropathyPhase 4PregabalinNCT00573261

A Randomized Double-Blind Study Testing the Effects of Pregabalin on Diabetic Neuropathy

A Phase 4 study testing Pregabalin in people with Diabetic Neuropathy, run by Duke University at 1 site in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record

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Trial summary

This study is designed to examine how pregabalin affects parameters of autonomic nerve regulation in correlation with change in pain, anxiety, and depressive symptoms in patients with diabetic neuropathy. Read more about this study

Who is it for?: Ages 18 years and older
Conditions the study is for: Diabetic Neuropathy
What is being tested?: Pregabalin
Could I receive a placebo?: Yes, some participants may receive a placebo
How many people: 40 participants
Where: 1 siteUnited States
Study dates: Mar 2006to May 2008
Phase: Phase 4
Are there results?: Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 18 years and older
All sexes
No healthy volunteers
Adult, Older adult

Who may be able to join

Outpatients aged 18 years or older
Meet criteria for diagnosis of diabetic neuropathy
Average daily pain scores greater than or equal to 4 by Visual Analog Scale
Ability to give informed consent
No pregnancy

Who cannot join

Patients with clinically significant psychiatric disorders requiring vigorous interventions, i.e., moderate to severe depressive disorder, psychotic disorders, PTSD, obsessive compulsive disorder, panic disorder, substance abuse, or personality disorders, or active suicidal/homicidal ideations, or past history of active suicidal ideation and/or attempts
Patients on gabapentin which cannot be discontinued, meaning a dose greater than 1200mg. If a patient is on a dose of gabapentin that is less than 1200mg and he or she is willing to stop taking the medication, he or she can participate in the study. These patients must take the last dose of gabapentin the night before starting the study.
Patients being non-compliant with diabetic control
Inability to wear the LifeShirt
Unable to participate or answer questions using a personal digital assistant input device

Trial locations and contacts

1 site in 1 country.

United States1 site

Duke University Medical Center
Durham, North Carolina, 27710

Other trials in United States

About this study

Official title: A Randomized, Double-Blind, Placebo-Controlled, Single Center Study Designed to Assess the Effects of Pregabalin on Change in Patients With Diabetic Neuropathy

Read the detailed description

This study is designed to primarily examine how pregabalin affects the autonomic nerve or sympathetic-parasympathetic regulation in patients with diabetic neuropathy and its relationship to neuropathic pain. The goals of this study include (1) assessing the change of parameters of autonomic nerve function such as heart rate variability (HRV), respiratory sinus arrhythmia (RSA), minute ventilation, and changes in objective sleep parameters measured by means of the LifeShirt, upon treatment of pregabalin in comparison to placebo; (2) assessing the symptom change of neuropathic pain upon treatment of pregabalin in comparison to placebo; (3) assessing the change of anxiety symptoms upon treatment of pregabalin in comparison to placebo; (4) assessing the change of depressive symptoms upon treatment of pregabalin in comparison to placebo; (5) assessing the relationship of autonomic nerve function with neuropathic pain at baseline prior to treatment and the correspondences to the study drug; (6) assessing the relationship of autonomic nerve function with anxiety and depressive symptoms at baseline prior to treatment and their correspondences to the study drug; (7) identifying sensitive and reliable parameters of autonomic nerve regulation as predictor(s) of the severity and improvement of neuropathic pain and/or anxiety; and (8) to assess the change in objective sleep parameters (EEG/EOG) by means of the LifeShirt, upon treatment of pregabalin in comparison to placebo

Conditions: Diabetic Neuropathy
Being tested: Pregabalin, Placebo
Keywords: Diabetic neuropathy, Pregabalin, Lyrica
Medical subject headings: Diabetic Neuropathies

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

PregabalinDrug
Also called Lyrica
Subjects will take pregabalin for the duration of four weeks. The dosage will range from 75 mg twice a day to 300 mg twice a day.
PlaceboDrug
Subjects will take placebo for the duration of four weeks. The dosage will range from 75 mg twice a day to 300 mg twice a day.

Study groups in NCT00573261
Study group	Role	What they receive
Pregabalin	Experimental	Pregabalin medication Receives: Drug: Pregabalin
Placebo	Placebo comparator	Placebo Receives: Drug: Placebo

What is being measured

The primary outcome is the main question the study is designed to answer.

Assessing the Change in Resting Blood Pressure Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.
Measured: baseline and at end of a 4-week intervention
Assessing the Change in Heart Rate by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.
The LifeShirt System, developed by VivoMetrics, is a lightweight vest with embedded sensors that continuously collect information on a range of cardiopulmonary parameters. It was used to collect and store the respiratory rate, posture, activity level, QRS complexes, and R-R intervals via a 3-axis accelerometer and a 3-lead, single channel electrocardiogram.
Measured: baseline and at end of a 4-week intervention
Assessing the Change in Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.
Heart rate variability parameters generated by the frequency domain analysis included: total power (area under the curve) over all frequencies, very low frequency (VLF, 0-0.04 Hz),low frequency (LF, 0.04-0.15 Hz), and high frequency (HF,0.15-0.4 Hz).
Measured: baseline and at end of a 4-week intervention
Assessing the Change in Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.
Heart Rate Variability parameters generated by the frequency domain analysis included: Low Frequency / High Frequency (LF/HF), as well as normalized LF (normalized LF=LF/[total power-VLF]) and normalized HF (normalized HF=HF/[total power-VLF]).
Measured: baseline and at end of a 4-week intervention
Assessing the Change of Parameters of Autonomic Nerve Function Such as Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.
Heart rate variability parameters yielded by time domain analysis included the mean of all R-R intervals (ANN), standard deviation of all R-R intervals (SDNN), root mean square of successive differences (RMSSD), and standard deviation of the averages of R-R intervals for all 5-minute segments within the block (SDANN).
Measured: baseline and at end of a 4-week intervention
Assessing the Change of Parameters of Autonomic Nerve Function Such as Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.
Heart rate variability parameters yielded by time domain analysis included the number of N-N intervals that differ by more than 50 milliseconds from adjacent intervals divided by the total number of all N-N intervals (pNN50).
Measured: baseline and at end of a 4-week intervention

Secondary outcomes (4)

To Assess the Change of Pain Symptoms Upon Treatment of Pregabalin in Comparison to Placebo.
Pain severity was evaluated using the Visual Analog Scale, the Modified Brief Pain Inventory-Short Form, and the Neuropathy Pain Scale. The Visual Analog Scale was scored within a range of 0-100 with 0=no pain and 100=the worst imaginable pain. The Brief Pain Inventory is made up of two parts: total pain and pain interference. The total pain score is the sum of most, least, average, and now pain scored within a range of 0-10 with 0=no pain and 10=pain as bad as you can imagine. The pain interference score is the sum of affective and activity interference - how pain interfered with general activity, mood, walking ability, normal work, relationships, sleep, and enjoyment of life. It was scored within a range of 0-10 with 0=pain does not interfere and 10=pain completely interferes. The Neuropathy Pain Scale total is the sum of 10 items -cold, sharp, deep, dull, hot, intense, itchy, sensitive, surface, and unpleasant pain scored within a range of 0-10 with 0=no pain and 10=most pain.
Measured: baseline and end of 4 week intervention
To Assess the Change of Anxiety Symptoms Upon Treatment of Pregabalin in Comparison to Placebo.
Anxiety symptoms were measured using the Spielberger State-Trait Anxiety Inventory Scale (STAI) for symptoms of anxiety. State anxiety: score range, 20-80 (higher score=greater levels of state anxiety). Trait anxiety: score range, 20-80 (higher score=greater levels of trait anxiety).
Measured: baseline and at end of a 4-week intervention
To Assess the Change of Depressive Symptoms Upon Treatment of Pregabalin in Comparison to Placebo.
The Beck Depression Inventory Scale measures symptoms of depression, score range, 0-63 (higher score=greater severity of depressive symptoms)
Measured: baseline and at end of a 4-week intervention
To Assess the Change in Disability Scale Upon Treatment of Pregabalin in Comparison to Placebo.
The Sheehan Disability Scale was used to evaluate functional impairment in work/school, social and family life, score range, 0-10; the 3 items can be summed into a single dimensional measure of global functional impairment that ranges from 0(unimpaired) to 30 (highly impaired).
Measured: baseline and at end of a 4-week intervention

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

Mar 2006May 2008

First posted14 Dec 2007 (estimated)
Study startMar 2006
Primary completionMay 2008
Study completionMay 2008

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
Publications (1)Papers the sponsor has linked to this study.
Other trials for Diabetic NeuropathyStudies of the same condition, open and under way.
More trials run by Duke UniversityThe sponsor's other registered studies.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase 4
Primary purpose: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Masking: Quadruple blind
Who is masked: Participant, Care provider, Investigator, Outcomes assessor
Enrolment: 40 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT00573261
Sponsor's protocol ID: Pro00009557
Other IDs: 2005-0003, 7511-05-8
Acronym: Pregabalin
Status last verified: Jul 2013
First submitted: 12 Dec 2007
Last updated: 21 Jul 2014
Results posted: Yes, on ClinicalTrials.gov
Data monitoring committee: No

Publications

Jiang W, Ladd S, Martsberger C, Feinglos M, Spratt SE, Kuchibhatla M, Green J, Krishnan R. Effects of pregabalin on heart rate variability in patients with painful diabetic neuropathy. J Clin Psychopharmacol. 2011 Apr;31(2):207-13. doi: 10.1097/JCP.0b013e31820f4f57.
PubMed 21346609

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See locations

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All Diabetic Neuropathy trials

Study at a glance

From the registry record, last updated by the sponsor on 21 Jul 2014. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: A Randomized, Double-Blind, Placebo-Controlled, Single Center Study Designed to Assess the Effects of Pregabalin on Change in Patients With Diabetic Neuropathy
ClinicalTrials.gov ID: NCT00573261
Acronym / sponsor ID: Pregabalin / Pro00009557
Conditions: Diabetic Neuropathy
Keywords: Diabetic neuropathy, Pregabalin, Lyrica
Phase: Phase 4
Study type: Interventional
Recruitment status: Completed
Enrolment: 40 participants (actual)
Lead sponsor: Duke UniversityUniversity, hospital or other
Collaborators: Pfizer
Study start: Mar 2006
Primary completion: May 2008 (actual)
Study completion: May 2008 (actual)
First posted: 14 Dec 2007 (estimated)
Results: Posted 18 Jul 2013

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Detailed description

Study design

Primary purpose: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Masking: Quadruple blind (participant, care provider, investigator, outcomes assessor)
Number of arms: 2

Arm	Type	Receives
Pregabalin	Experimental	Drug: PregabalinPregabalin medication
Placebo	Placebo comparator	Drug: PlaceboPlacebo

Who may qualify

Ages: 18 years and older
Sex: All
Healthy volunteers: Not accepted
Age groups: Adult, Older adult

Key inclusion criteria (5 listed)

Outpatients aged 18 years or older
Meet criteria for diagnosis of diabetic neuropathy
Average daily pain scores greater than or equal to 4 by Visual Analog Scale
Ability to give informed consent
No pregnancy

Key exclusion criteria (5 listed)

Patients with clinically significant psychiatric disorders requiring vigorous interventions, i.e., moderate to severe depressive disorder, psychotic disorders, PTSD, obsessive compulsive disorder, panic disorder, substance abuse, or personality disorders, or active suicidal/homicidal ideations, or past history of active suicidal ideation and/or attempts
Patients on gabapentin which cannot be discontinued, meaning a dose greater than 1200mg. If a patient is on a dose of gabapentin that is less than 1200mg and he or she is willing to stop taking the medication, he or she can participate in the study. These patients must take the last dose of gabapentin the night before starting the study.
Patients being non-compliant with diabetic control
Inability to wear the LifeShirt
Unable to participate or answer questions using a personal digital assistant input device

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
PregabalinAlso: LyricaSubjects will take pregabalin for the duration of four weeks. The dosage will range from 75 mg twice a day to 300 mg twice a day.	Drug	Pregabalin
PlaceboSubjects will take placebo for the duration of four weeks. The dosage will range from 75 mg twice a day to 300 mg twice a day.	Drug	Placebo

Primary outcome

Assessing the Change in Resting Blood Pressure Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.
Time frame: baseline and at end of a 4-week intervention
Assessing the Change in Heart Rate by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.
Time frame: baseline and at end of a 4-week intervention
The LifeShirt System, developed by VivoMetrics, is a lightweight vest with embedded sensors that continuously collect information on a range of cardiopulmonary parameters. It was used to collect and store the respiratory rate, posture, activity level, QRS complexes, and R-R intervals via a 3-axis accelerometer and a 3-lead, single channel electrocardiogram.
Assessing the Change in Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.
Time frame: baseline and at end of a 4-week intervention
Heart rate variability parameters generated by the frequency domain analysis included: total power (area under the curve) over all frequencies, very low frequency (VLF, 0-0.04 Hz),low frequency (LF, 0.04-0.15 Hz), and high frequency (HF,0.15-0.4 Hz).
Assessing the Change in Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.
Time frame: baseline and at end of a 4-week intervention
Heart Rate Variability parameters generated by the frequency domain analysis included: Low Frequency / High Frequency (LF/HF), as well as normalized LF (normalized LF=LF/[total power-VLF]) and normalized HF (normalized HF=HF/[total power-VLF]).
Assessing the Change of Parameters of Autonomic Nerve Function Such as Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.
Time frame: baseline and at end of a 4-week intervention
Heart rate variability parameters yielded by time domain analysis included the mean of all R-R intervals (ANN), standard deviation of all R-R intervals (SDNN), root mean square of successive differences (RMSSD), and standard deviation of the averages of R-R intervals for all 5-minute segments within the block (SDANN).
Assessing the Change of Parameters of Autonomic Nerve Function Such as Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.
Time frame: baseline and at end of a 4-week intervention
Heart rate variability parameters yielded by time domain analysis included the number of N-N intervals that differ by more than 50 milliseconds from adjacent intervals divided by the total number of all N-N intervals (pNN50).

4 secondary outcomes

To Assess the Change of Pain Symptoms Upon Treatment of Pregabalin in Comparison to Placebo.
Time frame: baseline and end of 4 week intervention
To Assess the Change of Anxiety Symptoms Upon Treatment of Pregabalin in Comparison to Placebo.
Time frame: baseline and at end of a 4-week intervention
To Assess the Change of Depressive Symptoms Upon Treatment of Pregabalin in Comparison to Placebo.
Time frame: baseline and at end of a 4-week intervention
To Assess the Change in Disability Scale Upon Treatment of Pregabalin in Comparison to Placebo.
Time frame: baseline and at end of a 4-week intervention

Results and safety

Results posted to the registry on 18 Jul 2013, as reported by the sponsor. Figures are copied from the record, not re-analysed. Full results on ClinicalTrials.gov.

Participant flow

Group	Started	Completed
Placebo	20	14
Pregabalin	20	15

Primary outcome: Assessing the Change in Resting Blood Pressure Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.

Time frame: baseline and at end of a 4-week intervention. Mean (Standard Deviation). Unit: mm Hg

Measure	Placebo n = 13	Pregabalin n = 15
Systolic Blood Pressure (mm Hg)	-7.63 (10.46)	-8.98 (17.61)
Diastolic Blood Pressure (mm Hg)	-4.41 (7.79)	-4.93 (8.64)

Population analysed: A data card failure of the baseline heart rate record with the VivoMetrics system occurred for one subject who had completed baseline and 4-week assessments, leaving 28 subjects (n=13 in placebo, n=15 in pregabalin)having both completed baseline and end of 4-week R-R intervals for heart rate variability analysis.

Primary outcome: Assessing the Change in Heart Rate by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.

Time frame: baseline and at end of a 4-week intervention. Mean (Standard Deviation). Unit: Beats Per Minute

Measure	Placebo n = 13	Pregabalin n = 15
Value	-2.94 (6.96)	-3.49 (5.51)

Primary outcome: Assessing the Change in Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.

Time frame: baseline and at end of a 4-week intervention. Mean (Standard Deviation). Unit: Hertz (Hz)

Measure	Placebo n = 13	Pregabalin n = 15
Total Power	45.29 (418.09)	-140.99 (629.81)
Low Frequency	32.41 (229.51)	-67.06 (252.06)
High Frequency	-12.19 (79.91)	-41.37 (175.89)

Primary outcome: Assessing the Change in Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.

Time frame: baseline and at end of a 4-week intervention. Mean (Standard Deviation). Unit: Ratio

Measure	Placebo n = 13	Pregabalin n = 15
Low frequency/High frequency	0.37 (0.33)	-1.30 (2.89)
Normalized low frequency	0.0066 (0.023)	-0.049 (0.092)
Normalized high frequency	-0.038 (0.066)	0.039 (0.094)

4 secondary outcomes are reported in the full results.

Adverse events

Time frame: Participants were contacted by phone starting at the end of week 1 for potential adverse effects and titration of the study drug throughout 4-week treatment period.. Other adverse events reported at 3% frequency or more

Group	Serious adverse events	Other adverse events	Deaths
Placebo	0 of 14 (0%)	0 of 14 (0%)	Not reported
Pregabalin	0 of 15 (0%)	3 of 15 (20%)	Not reported

Limitations and caveats (from the sponsor): The study has a high dropout, which might have reduced the power of the analysis. One of the major reasons that many patients were not able to participate was an inability to commit to the relatively intense and frequent assessments.

Loading the posted results from ClinicalTrials.gov…

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 21 Jul 2014.
Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
Results publication: PubMed 21346609Jiang W, Ladd S, Martsberger C, Feinglos M, Spratt SE, Kuchibhatla M, Green J, Krishnan R. Effects of pregabalin on heart rate variability in patients with painful diabetic neuropathy. J Clin Psychopharmacol. 2011 Apr;31(2):207-13. doi: 10.1097/JCP.0b013e31820f4f57.

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Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Wei Jiang, M.D. principal investigator

Duke University

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A Phase 4 study testing Pregabalin in people with Diabetic Neuropathy, run by Duke University at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 5 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 21 Jul 2014. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

Yes. Results are posted in the registry (first posted 18 Jul 2013). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Assessing the Change in Resting Blood Pressure Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy. (time frame: baseline and at end of a 4-week intervention). The study lists 6 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT00573261, which also lists 1 linked publication.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 21 Jul 2014.