Title

Efficacy and Safety Study of ARC-4558 for Management of Pain Associated With Painful Diabetic Neuropathy
A Multicenter, Randomized, Double-Blind, Parallel-Group Study Comparing the Efficacy and Safety of Clonidine Topical Gel, 0.1% With Placebo in the Management of Pain Associated With Painful Diabetic Neuropathy
  • Phase

    Phase 2
  • Study Type

    Interventional
  • Intervention/Treatment

    clonidine ...
  • Study Participants

    180
The purpose of this study is to determine whether ARC-4558 is effective in managing pain associated with painful diabetic neuropathy.
Study Started
May 31
2008
Primary Completion
Dec 31
2009
Study Completion
Feb 28
2010
Results Posted
Nov 08
2016
Estimate
Last Update
Nov 08
2016
Estimate

Drug Placebo Gel

TID x 12 weeks

Drug Clonidine Topical Gel (ARC-4558)

TID x 12 weeks

Placebo Gel Placebo Comparator

Placebo Gel is vehicle without clonidine

Clonidine Topical Gel (ARC-4558) Active Comparator

Clonidine Topical Gel contains 0.1% clonidine hydrochloride

Criteria

Inclusion Criteria:

has Type 1 or Type 2 diabetes mellitus
has a history of chronic pain attributable to a symmetrical stocking distribution neuropathy in the lower extremities for a duration of at least six months but less than or equal to five years prior to Screening

Exclusion Criteria:

has neuropathy secondary to non-diabetic causes
has a significant neurological disorder or a condition that can cause symptoms that mimic peripheral neuropathy or might confound assessment of PDN
has other chronic pain with intensity at or greater than the bilateral pain in the feet/toes
is using an implanted medical device (eg, spinal cord stimulator, intrathecal pump, or peripheral nerve stimulator) for the treatment of pain
is pregnant or lactating

Summary

Placebo Gel

Clonidine Topical Gel (ARC-4558)

All Events

Event Type Organ System Event Term Placebo Gel Clonidine Topical Gel (ARC-4558)

Change From Baseline to Week 12 in the Average Daily Pain NPRS (Numeric Pain Rating Scale) Score; mLOCF Imputation

Pain in the feet was scored daily at bedtime by the subject on a 0-10 numeric pain rating scale (NPRS) through Day 84. Subjects were asked to record average pain in the feet over the past 24 hours. A score of 0 indicated "no pain" and a score of 10 was "worst possible pain". The change in pain is represented as Week 12 minus Baseline, so greater negative numbers represent more improvement (more pain relief).

Placebo Gel

All subjects

-1.9
units on a scale (Mean)
Standard Deviation: 1.9

Capsaicin response ≥ 2

-1.5
units on a scale (Mean)
Standard Deviation: 1.8

Clonidine Topical Gel (ARC-4558)

All subjects

-2.4
units on a scale (Mean)
Standard Deviation: 2.1

Capsaicin response ≥ 2

-2.7
units on a scale (Mean)
Standard Deviation: 1.9

Change From Baseline in Average Daily Pain NPRS Score for Each Week of Treatment; mLOCF Imputation

Pain in the feet was scored daily at bedtime by the subject on a 0-10 numeric pain rating scale (NPRS). Subjects were asked to record average pain in the feet over the past 24 hours. A score of 0 indicated "no pain" and a score of 10 was "worst possible pain". A weekly average was calculated from the daily scores for each week. The change in pain is represented as the average weekly score minus Baseline, so greater negative numbers represent more improvement (more pain relief).

Placebo Gel

Week 1

-0.6
units on a scale (Mean)
Standard Deviation: 1.01

Week 10

-1.9
units on a scale (Mean)
Standard Deviation: 1.98

Week 11

-1.9
units on a scale (Mean)
Standard Deviation: 1.93

Week 12

-1.9
units on a scale (Mean)
Standard Deviation: 1.91

Week 2

-1.0
units on a scale (Mean)
Standard Deviation: 1.30

Week 3

-1.2
units on a scale (Mean)
Standard Deviation: 1.47

Week 4

-1.5
units on a scale (Mean)
Standard Deviation: 1.63

Week 5

-1.7
units on a scale (Mean)
Standard Deviation: 1.77

Week 6

-1.8
units on a scale (Mean)
Standard Deviation: 1.84

Week 7

-1.8
units on a scale (Mean)
Standard Deviation: 1.83

Week 8

-1.9
units on a scale (Mean)
Standard Deviation: 1.93

Week 9

-1.9
units on a scale (Mean)
Standard Deviation: 1.96

Clonidine Topical Gel (ARC-4558)

Week 1

-0.7
units on a scale (Mean)
Standard Deviation: 1.34

Week 10

-2.4
units on a scale (Mean)
Standard Deviation: 2.06

Week 11

-2.3
units on a scale (Mean)
Standard Deviation: 2.12

Week 12

-2.4
units on a scale (Mean)
Standard Deviation: 2.12

Week 2

-1.0
units on a scale (Mean)
Standard Deviation: 1.45

Week 3

-1.5
units on a scale (Mean)
Standard Deviation: 1.58

Week 4

-1.6
units on a scale (Mean)
Standard Deviation: 1.71

Week 5

-1.7
units on a scale (Mean)
Standard Deviation: 1.65

Week 6

-1.8
units on a scale (Mean)
Standard Deviation: 1.74

Week 7

-2.1
units on a scale (Mean)
Standard Deviation: 1.86

Week 8

-2.2
units on a scale (Mean)
Standard Deviation: 1.92

Week 9

-2.3
units on a scale (Mean)
Standard Deviation: 1.95

Change From Baseline to Week 12 in the Worst Daily Pain NPRS Score; mLOCF Imputation

Pain in the feet was scored daily at bedtime by the subject on a 0-10 numeric pain rating scale. Subjects were asked to record the worst pain in their feet over the past 24 hours. A score of 0 indicated "no pain" and a score of 10 was "worst possible pain". The change in pain is represented as Week 12 minus Baseline, so greater negative numbers represent greater improvement (greater pain relief).

Placebo Gel

-2.1
units on a scale (Mean)
Standard Deviation: 2.1

Clonidine Topical Gel (ARC-4558)

-2.5
units on a scale (Mean)
Standard Deviation: 2.3

Percentage of Subjects Who Experience at Least 30% Reduction in Average Daily Pain From Baseline; mLOCF Imputation

Pain in the feet was scored daily at bedtime by the subject on a 0-10 numeric pain rating scale (NPRS). Subjects were asked to record average pain in the feet over the past 24 hours. A score of 0 indicated "no pain" and a score of 10 was "worst possible pain".

Placebo Gel

47.0
percentage of subjects

Clonidine Topical Gel (ARC-4558)

52.0
percentage of subjects

Percentage of Subjects Who Experience at Least 50% Reduction in Average Daily Pain From Baseline; mLOCF Imputation

Pain in the feet was scored daily at bedtime by the subject on a 0-10 numeric pain rating scale (NPRS). Subjects were asked to record average pain in the feet over the past 24 hours. A score of 0 indicated "no pain" and a score of 10 was "worst possible pain".

Placebo Gel

32.0
percentage of subjects

Clonidine Topical Gel (ARC-4558)

37.0
percentage of subjects

Change From Baseline in the Brief Pain Inventory (BPI) Severity Scale at Week 12; mLOCF Imputation

The Brief Pain Inventory was completed by the subject at clinic visits. The Severity Scale (of 0 to 40) is a composite score, which is the sum of the individual ratings for worst pain, least pain, average pain, and current pain. Each individual question is rated on a scale of 0 to 10, where 0 indicates "No Pain" and 10 indicates "Pain as bad as you can imagine". The change in pain severity is represented as Week 12 minus Baseline, so greater negative numbers represent greater improvement (pain relief).

Placebo Gel

-7.9
units on a scale (Mean)
Standard Deviation: 8.5

Clonidine Topical Gel (ARC-4558)

-9.6
units on a scale (Mean)
Standard Deviation: 8.7

Change From Baseline in the Brief Pain Inventory Functional Interference Scale at Week 12; mLOCF Imputation

The Brief Pain Inventory was completed by the subject at clinic visits. The Functional Interference Scale (of 0 to 70) is a composite score that measures the degree to which pain interferes with mood, walking, work, relationships, sleep, general activity, and enjoyment of life. The composite score is a sum of the seven individual question scores. Each individual question is rated in reference to pain over the past 24 hours on a scale of 0 to 10, where 0 indicates that pain "does not interfere" and 10 indicates that pain "completely interferes" with that function, so lower scores represent better outcomes on this scale. The change in functional interference is represented as Week 12 minus Baseline, so greater negative numbers represent more improvement.

Placebo Gel

-15.1
units on a scale (Mean)
Standard Deviation: 14.9

Clonidine Topical Gel (ARC-4558)

-17.3
units on a scale (Mean)
Standard Deviation: 17.5

Change From Baseline to Week 12 in Overall Quality of Sleep (Chronic Pain Sleep Inventory)

Subjects rated overall quality of sleep over the past week using a 100 mm Visual Analog Scale (VAS) where 100=Excellent and 0=Very Poor. This scale was completed during clinic visits. Change from Baseline is a positive value where quality of sleep improved.

Placebo Gel

17.7
units on a scale (Mean)
Standard Deviation: 33.4

Clonidine Topical Gel (ARC-4558)

19.2
units on a scale (Mean)
Standard Deviation: 31.3

Change From Baseline to Week 12 in the Depression Score of the Hospital Anxiety and Depression Scale (HADS)

The HADS was completed at the Baseline and Week 12 clinic visits. The Depression Score component of the HADS includes 7 questions, each with 4 possible answer choices (rated 0 to 3). The composite score is created by adding the scores of the 7 individual questions. A score of 0 to 7 is Normal, 8-10 indicates Mild Depression, 11-14 indicates Moderate Depression, and 15-21 indicates Severe Depression. The change from Baseline is calculated as the Week 12 composite score minus the Baseline composite score.

Placebo Gel

-0.4
units on a scale (Mean)
Standard Deviation: 2.6

Clonidine Topical Gel (ARC-4558)

-0.9
units on a scale (Mean)
Standard Deviation: 2.3

Change From Baseline to Week 12 in the Anxiety Score of the Hospital Anxiety and Depression Scale (HADS)

The HADS was completed at the Baseline and Week 12 clinic visits. The Anxiety Score component of the HADS includes 7 questions, each with 4 possible answer choices (rated 0 to 3). The composite score is created by adding the scores of the 7 individual questions. A score of 0 to 7 is Normal, 8-10 indicates Mild Anxiety, 11-14 indicates Moderate Anxiety, and 15-21 indicates Severe Anxiety. The change from Baseline is calculated as the Week 12 composite score minus the Baseline composite score.

Placebo Gel

-0.6
units on a scale (Mean)
Standard Deviation: 2.67

Clonidine Topical Gel (ARC-4558)

-1.1
units on a scale (Mean)
Standard Deviation: 3.14

Change From Baseline to Week 12 in the McGill Pain Questionnaire (Short Form) Total Score

The McGill Pain Questionnaire asks subjects to rate 15 different kinds of pain, each on a scale of 0 to 3 (0=None, 1=Mild, 2=Moderate, 3=Severe). The total score is a sum of the individual ratings and has a range from 0 to 45, where higher numbers indicate more pain. The 15 types of pain assessed are throbbing, shooting, stabbing, sharp, cramping, gnawing, hot-burning, aching, heavy, tender, splitting, tiring-exhausting, sickening, fearful, and punishing-cruel. This scale was completed at the Baseline and Week 12 clinic visits. The change from Baseline is calculated as the Week 12 total score minus the Baseline total score, so greater negative numbers indicate more improvement (pain relief).

Placebo Gel

-7.3
units on a scale (Mean)
Standard Deviation: 8.3

Clonidine Topical Gel (ARC-4558)

-8.7
units on a scale (Mean)
Standard Deviation: 9.8

Patient Global Impression of Change (PGIC) at Week 12

At Week 12 the subject was asked to rate their total improvement relative to Baseline, whether or not, in their judgement, it was due entirely to study drug treatment or not. Answer choices were: (+3) very much improved, (+2) much improved, (+1) minimally improved, (0) no change, (-1) minimally worse, (-2) much worse, (-3) very much worse.

Placebo Gel

Minimally Improved

31.8
percentage of subjects

Minimally Worse

1.2
percentage of subjects

Much Improved

32.9
percentage of subjects

No Change

21.2
percentage of subjects

Very Much Improved

11.8
percentage of subjects

Very Much Worse

1.2
percentage of subjects

Clonidine Topical Gel (ARC-4558)

Minimally Improved

28.2
percentage of subjects

Minimally Worse

1.2
percentage of subjects

Much Improved

27.1
percentage of subjects

No Change

22.4
percentage of subjects

Very Much Improved

21.2
percentage of subjects

Very Much Worse

Clinician Global Impression of Change (CGIC) at Week 12

At Week 12, the Investigator was asked to independently rate the subject's total improvement relative to Baseline, whether or not, in their judgement, it was due entirely to study drug treatment or not. Answer choices were: (+3) very much improved, (+2) much improved, (+1) minimally improved, (0) no change, (-1) minimally worse, (-2) much worse, (-3) very much worse.

Placebo Gel

Minimally Improved

27.9
percentage of subjects

Minimally Worse

2.3
percentage of subjects

Much Improved

38.4
percentage of subjects

No Change

25.6
percentage of subjects

Very Much Improved

5.8
percentage of subjects

Very Much Worse

Clonidine Topical Gel (ARC-4558)

Minimally Improved

24.7
percentage of subjects

Minimally Worse

1.2
percentage of subjects

Much Improved

30.6
percentage of subjects

No Change

27.1
percentage of subjects

Very Much Improved

16.5
percentage of subjects

Very Much Worse

Change in Blood Pressure From Baseline to Week 12

Systolic and Diastolic Blood Pressure were measured at clinic visits. This outcome assesses the change in blood pressure from Baseline to Week 12 of treatment.

Placebo Gel

Change in Diastolic BP

-0.2
mmHg (Mean)
Standard Deviation: 9.4

Change in Systolic BP

-0.4
mmHg (Mean)
Standard Deviation: 20.6

Clonidine Topical Gel (ARC-4558)

Change in Diastolic BP

1.0
mmHg (Mean)
Standard Deviation: 8.8

Change in Systolic BP

1.0
mmHg (Mean)
Standard Deviation: 13.9

Total

180
Participants

Age, Continuous

58.5
years (Mean)
Standard Deviation: 9.7

Region of Enrollment

Sex: Female, Male

Overall Study

Placebo Gel

Clonidine Topical Gel (ARC-4558)

Drop/Withdrawal Reasons

Placebo Gel

Clonidine Topical Gel (ARC-4558)