Trial Outcomes & Findings for Salsalate Therapy to Reduce Insulin Resistance and Cardiovascular Risk (NCT NCT00330733)

NCT ID: NCT00330733

Last Updated: 2020-01-21

Results Overview

Participants were admitted to the Clinical Research Units at 06:00-08:00 hours after an overnight fast. Euglycaemic-hyperinsulinaemic clamps were conducted at baseline and at the end of the study. Because salsalate therapy appears to decrease insulin clearance leading to higher circulating insulin levels during the clamp, we reduced the infusion rate of insulin in the active treatment arm by 20% (from 100 to 80 mUm-2 min-1) at the study end. Insulin solutions were prepared by the site pharmacist so that study staff remained blinded to drug assignment. Whole-body insulin sensitivity was estimated from glucose infusion rate (GIR) during last 30 min of insulin infusions.

Recruitment status

COMPLETED

Study phase

PHASE2/PHASE3

Target enrollment

71 participants

Primary outcome timeframe

3 months

Results posted on

2020-01-21

Participant Flow

Participants were veterans aged 21-75 years with impaired fasting glucose (i.e. ≥5.6 but \<7 mmol/l) or impaired glucose tolerance (2 h glucose values ≥7.8 but \<11.1 mmol/l) during a standard 2 h 75 g OGTT. Study participants were recruited from clinics and hospitals throughout the Phoenix and Boston VA Health Care systems.

After enrolment there were 1 week screening, 3 week single-masked placebo run-in (to assess compliance) and 12 week randomised, double-masked treatment periods, with participants randomised 1:1 to receive salsalate or placebo. 78 individuals entered the run-in phase.

Participant milestones

Participant milestones
Measure
Placebo
Matching placebo
Salsalate
Salsalate therapy (Caraco Pharmaceutical Labs, Detroit, MI, USA) was initiated at 3.0 g/day and increased at weeks 2 and 4 of the treatment period to 3.5 and 4.0 g/day, respectively, in divided doses twice daily, as tolerated.
Overall Study
STARTED
37
34
Overall Study
Received Study Medication
36
34
Overall Study
COMPLETED
30
29
Overall Study
NOT COMPLETED
7
5

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Salsalate Therapy to Reduce Insulin Resistance and Cardiovascular Risk

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Placebo
n=36 Participants
Matching placebo
Salsalate Therapy
n=34 Participants
Salsalate therapy, double-masked. Salsalate (Caraco Pharmaceutical Labs, Detroit, MI, USA) was initiated at 3.0 g/day and increased at weeks 2 and 4 of the treatment period to 3.5 and 4.0 g/day, respectively, in divided doses twice daily, as tolerated for 12 weeks total.
Total
n=70 Participants
Total of all reporting groups
Age, Continuous
57 years
STANDARD_DEVIATION 9 • n=5 Participants
60 years
STANDARD_DEVIATION 6 • n=7 Participants
58 years
STANDARD_DEVIATION 8 • n=5 Participants
Sex: Female, Male
Female
1 Participants
n=5 Participants
2 Participants
n=7 Participants
3 Participants
n=5 Participants
Sex: Female, Male
Male
35 Participants
n=5 Participants
32 Participants
n=7 Participants
67 Participants
n=5 Participants
Region of Enrollment
United States
36 Participants
n=5 Participants
34 Participants
n=7 Participants
70 Participants
n=5 Participants
Insulin sensitivity
4.08 mg/ kg . min
STANDARD_DEVIATION 1.46 • n=5 Participants
3.8 mg/ kg . min
STANDARD_DEVIATION 1.0 • n=7 Participants
3.93 mg/ kg . min
STANDARD_DEVIATION 1.27 • n=5 Participants
Oral Glucose Tolerance Test
167 mg/dl. min
STANDARD_DEVIATION 21 • n=5 Participants
165 mg/dl. min
STANDARD_DEVIATION 17 • n=7 Participants
166 mg/dl. min
STANDARD_DEVIATION 19 • n=5 Participants
Fasting glucose
105 mg/dl
STANDARD_DEVIATION 12 • n=5 Participants
103 mg/dl
STANDARD_DEVIATION 10 • n=7 Participants
104 mg/dl
STANDARD_DEVIATION 11 • n=5 Participants

PRIMARY outcome

Timeframe: 3 months

Population: analysis was performed on all participants with available baseline and final clamp studies

Participants were admitted to the Clinical Research Units at 06:00-08:00 hours after an overnight fast. Euglycaemic-hyperinsulinaemic clamps were conducted at baseline and at the end of the study. Because salsalate therapy appears to decrease insulin clearance leading to higher circulating insulin levels during the clamp, we reduced the infusion rate of insulin in the active treatment arm by 20% (from 100 to 80 mUm-2 min-1) at the study end. Insulin solutions were prepared by the site pharmacist so that study staff remained blinded to drug assignment. Whole-body insulin sensitivity was estimated from glucose infusion rate (GIR) during last 30 min of insulin infusions.

Outcome measures

Outcome measures
Measure
Placebo
n=29 Participants
Placebo: Matching placebo
Salsalate Therapy
n=29 Participants
Salsalate: Salsalate therapy
Change in Systemic Glucose Disposal- Glucose Infusion Rates
1 percent change from baseline
Interval -39.0 to 56.0
6 percent change from baseline
Interval -20.0 to 61.0

SECONDARY outcome

Timeframe: 3 months

Population: analysis was performed on all participants with available baseline and final clamp studies

Outcome measures

Outcome measures
Measure
Placebo
n=30 Participants
Placebo: Matching placebo
Salsalate Therapy
n=28 Participants
Salsalate: Salsalate therapy
Glucose Area Under the Curve in These Subjects
8.98 mmol/l/hr
Standard Deviation 1.19
8.74 mmol/l/hr
Standard Deviation 1.33

SECONDARY outcome

Timeframe: 8 and 12 weeks

Population: Seventy-eight individuals entered the placebo run-in phase. Of these, 71 were randomised and 70 returned to receive study medication

Plasma C-reactive protein was measured by PVAHS clinical laboratory. Data are reported as change from baseline at 8 and 12 weeks.

Outcome measures

Outcome measures
Measure
Placebo
n=36 Participants
Placebo: Matching placebo
Salsalate Therapy
n=34 Participants
Salsalate: Salsalate therapy
Plasma CRP
Change in CRP at 12 weeks
-0.1 mg/l
Interval -2.6 to 3.6
-.3 mg/l
Interval -5.6 to 4.5
Plasma CRP
Change in CRP at 8 weeks
0 mg/l
Interval -2.3 to 4.1
-0.8 mg/l
Interval -8.0 to 4.5

SECONDARY outcome

Timeframe: Baseline and 12 weeks

Population: Analysis was performed on all participants with available baseline and final clamp studies

Endothelial-mediated arterial responses using peripheral arterial tonometry (PAT; Itamar Medical, Caesarea, Israel).

Outcome measures

Outcome measures
Measure
Placebo
n=26 Participants
Placebo: Matching placebo
Salsalate Therapy
n=27 Participants
Salsalate: Salsalate therapy
Endothelial Function
Pat Index baseline
1.8 index
Standard Error .5
1.9 index
Standard Error .5
Endothelial Function
Pat Index 12 week
1.7 index
Standard Error .5
1.7 index
Standard Error .6

SECONDARY outcome

Timeframe: 8 and 12 weeks

Population: Seventy-eight individuals entered the placebo run-in phase. Of these, 71 were randomised and 70 returned to receive study medication

Plasma IL-6 was measured by ELISA. Data are reported as change from baseline at 8 and 12 weeks.

Outcome measures

Outcome measures
Measure
Placebo
n=36 Participants
Placebo: Matching placebo
Salsalate Therapy
n=34 Participants
Salsalate: Salsalate therapy
Plasma Interleukin 6
Change in IL-6 at 8 weeks
0.1 pg/ml
Interval -0.5 to 0.9
0 pg/ml
Interval -0.2 to 0.4
Plasma Interleukin 6
Change in IL-6 at 12 weeks
0.2 pg/ml
Interval -0.3 to 0.7
0 pg/ml
Interval -0.2 to 0.7

SECONDARY outcome

Timeframe: 8 and 12 weeks

Population: Seventy-eight individuals entered the placebo run-in phase. Of these, 71 were randomised and 70 returned to receive study medication

Plasma soluble VCAM was measured by ELISA. Data are reported as change from baseline at 8 and 12 weeks.

Outcome measures

Outcome measures
Measure
Placebo
n=36 Participants
Placebo: Matching placebo
Salsalate Therapy
n=34 Participants
Salsalate: Salsalate therapy
Plasma sVCAM
Change in sVCAM at 8 weeks
-12 ng/ml
Interval -162.0 to 75.0
-5 ng/ml
Interval -105.0 to 272.0
Plasma sVCAM
Change in sVCAM at 12 weeks
9 ng/ml
Interval -145.0 to 166.0
171 ng/ml
Interval 7.0 to 320.0

SECONDARY outcome

Timeframe: 8 and 12 weeks

Population: Seventy-eight individuals entered the placebo run-in phase. Of these, 71 were randomised and 70 returned to receive study medication

Plasma soluble Adiponectin was measured by ELISA. Data are reported as change from baseline at 8 and 12 weeks.

Outcome measures

Outcome measures
Measure
Placebo
n=36 Participants
Placebo: Matching placebo
Salsalate Therapy
n=34 Participants
Salsalate: Salsalate therapy
Plasma Adiponectin
Change in adiponectin at 8 weeks
-0.5 μg/ml
Interval -1.1 to 0.3
1.3 μg/ml
Interval -0.1 to 2.1
Plasma Adiponectin
Change in adiponectin at 12 weeks
-0.1 μg/ml
Interval -1.0 to 1.7
1.2 μg/ml
Interval -0.4 to 2.8

Adverse Events

Placebo

Serious events: 0 serious events
Other events: 7 other events
Deaths: 0 deaths

Salsalate Therapy

Serious events: 0 serious events
Other events: 12 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure
Placebo
n=36 participants at risk
Placebo: Matching placebo The frequency of tinnitus was relatively low (n=4 for salsalate, n= 2 for placebo), only one instance was graded \> mild. Gastrointestinal complaints did not differ between groups (n= 8 for salsalate, n=5 for placebo). No hypoglycaemia occurred.
Salsalate Therapy
n=34 participants at risk
Salsalate: Salsalate therapy The frequency of tinnitus was relatively low (n=4 for salsalate, n= 2 for placebo), only one instance was graded \> mild. Gastrointestinal complaints did not differ between groups (n= 8 for salsalate, n=5 for placebo). No hypoglycaemia occurred.
Ear and labyrinth disorders
tinnitus
5.6%
2/36 • Number of events 2 • 14 weeks (12 weeks active treatment + 2-week follow-up).
11.8%
4/34 • Number of events 4 • 14 weeks (12 weeks active treatment + 2-week follow-up).
Gastrointestinal disorders
nausea
13.9%
5/36 • Number of events 5 • 14 weeks (12 weeks active treatment + 2-week follow-up).
23.5%
8/34 • Number of events 8 • 14 weeks (12 weeks active treatment + 2-week follow-up).

Additional Information

Peter Reaven

Phoenix VA Health Care System

Phone: 602 277 5551

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place