The effect of a thiazolidinedione drug, troglitazone, on glycemia in patients with type 2 diabetes mellitus poorly controlled with sulfonylurea and metformin. A multicenter, randomized, double-blind, placebo-controlled trial.
BACKGROUND
The thiazolidinediones are a new class of antidiabetes medication that enhances the actions of insulin in muscle, liver, and adipose tissue. Data have been lacking on their use in combination with both sulfonylurea and metformin among patients for whom insulin is the usual therapeutic alternative for improved glycemic control.


OBJECTIVE
To determine the effects of troglitazone on hemoglobin A(1c) level in patients treated with maximum tolerated doses of sulfonylurea and metformin who have hemoglobin A(1c) levels of at least 0.085 (8.5%). This trial was completed before troglitazone was taken off the U.S. market.


METHODS
Randomized, double-blind, placebo-controlled trial, followed by an open-label extension during which all patients received troglitazone.


METHODS
16 outpatient clinics in Canada.


METHODS
200 patients (mean age, 59 years) with type 2 diabetes mellitus and hemoglobin A(1c) levels at least 0.085 (8.5%) (mean hemoglobin A(1c) level, 0.097 [9.7%] and mean fasting plasma glucose level, 12.9 mmol/L [233 mg/dL]) while receiving maximum doses of sulfonylurea and metformin.


METHODS
Levels of hemoglobin A(1c), fasting plasma glucose, total insulin, triglycerides, total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol.


RESULTS
Troglitazone, 400 mg/d, when added to sulfonylurea and metformin, significantly decreased hemoglobin A(1c) level by 0.014 +/- 0.002 (95% CI, 0.0167 to 0.0109; P < 0.001) (1.4% +/- 0.2% [CI, 1.67% to 1.09%]) and insulin by 19 +/- 4 pmol/L (CI, 30 to 10 pmol/L; P < 0.001). At 6 months, 43% of troglitazone-treated patients achieved hemoglobin A(1c) levels of 0.08 (8%) or lower compared with 6% of placebo recipients. Efficacy was maintained at 12 months.


CONCLUSIONS
The thiazolidinedione troglitazone, at a dosage of 400 mg/d, is effective when used in combination with sulfonylurea and metformin. Thiazolidinediones may therefore offer an effective alternative to insulin for patients treated with sulfonylurea and metformin who do not achieve adequate glycemic control.
Yale
J F
JF
McGill University Health Centre, 687 Pine Avenue West, Room H685, Montreal, Quebec H3A 1A1, Canada.
Valiquett
T R
TR
Ghazzi
M N
MN
Owens-Grillo
J K
JK
Whitcomb
R W
RW
Foyt
H L
HL
D001786:Blood Glucose / Q000378:metabolism*; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D002839:Chromans / Q000009:adverse effects / Q000627:therapeutic use*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy*; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007004:Hypoglycemic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D007328:Insulin / Q000097:blood; D008297:Male; D008687:Metformin / Q000627:therapeutic use; D008875:Middle Aged; D013453:Sulfonylurea Compounds / Q000627:therapeutic use; D013844:Thiazoles / Q000009:adverse effects / Q000627:therapeutic use*; D045162:Thiazolidinediones; D017211:Treatment Failure; D014280:Triglycerides / Q000378:metabolism; D000077288:Troglitazone
D001786:Blood Glucose; D002784:Cholesterol; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D002839:Chromans; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin; D008687:Metformin; D013453:Sulfonylurea Compounds; D013844:Thiazoles; D045162:Thiazolidinediones; D014280:Triglycerides; D000077288:Troglitazone