OBJECTIVEThe Qatar Study was designed to examine the efficacy of combination therapy with exenatide plus pioglitazone versus basal/bolus insulin in patients with long-standing poorly controlled type 2 diabetes mellitus (T2DM) on metformin plus a sulfonylurea.RESEARCH DESIGN AND METHODSThe study randomized 231 patients with poorly controlled (HbA1c >7.5%, 58 mmol/mol) T2DM on a sulfonylurea plus metformin to receive 1) pioglitazone plus weekly exenatide (combination therapy) or 2) basal plus prandial insulin (insulin therapy) to maintain HbA1c <7.0% (53 mmol/mol).RESULTSAfter a mean follow-up of 12 months, combination therapy caused a robust decrease in HbA1c from 10.0 ± 0.6% (86 ± 5.2 mmol/mol) at baseline to 6.1 ± 0.1% (43 ± 0.7 mmol/mol) compared with 7.1 ± 0.1% (54 ± 0.8 mmol/mol) in subjects receiving insulin therapy. Combination therapy was effective in lowering the HbA1c independent of sex, ethnicity, BMI, or baseline HbA1c. Subjects in the insulin therapy group experienced significantly greater weight gain and a threefold higher rate of hypoglycemia than patients in the combination therapy group.CONCLUSIONSCombination exenatide/pioglitazone therapy is a very effective and safe therapeutic option in patients with long-standing poorly controlled T2DM on metformin plus a sulfonylurea.

IntroductionTo assess the effect of exenatide and pioglitazone or basal-bolus insulin on diabetic peripheral neuropathy (DPN) in patients with poorly controlled type 2 diabetes (T2D).Research design and methodsThis is a substudy of the Qatar Study, an open-label, randomized controlled trial. 38 subjects with poorly controlled T2D were studied at baseline and 1-year follow-up and 18 control subjects were assessed at baseline only. A combination of exenatide (2 mg/week) and pioglitazone (30 mg/day) or glargine with aspart insulin were randomly assigned to patients to achieve an HbA1c <53 mmol/mol (<7%). DPN was assessed with corneal confocal microscopy (CCM), DN4, vibration perception and sudomotor function.ResultsSubjects with T2D had reduced corneal nerves, but other DPN measures were comparable with the control group. In the combination treatment arm (n=21), HbA1c decreased by 35.2 mmol/mol (3.8 %) (p<0.0001), body weight increased by 5.6 kg (p<0.0001), corneal nerve branch density increased (p<0.05), vibration perception worsened (p<0.05), and DN4 and sudomotor function showed no change. In the insulin treatment arm, HbA1c decreased by 28.7 mmol/mol (2.7 %) (p<0.0001), body weight increased by 4.6 kg (p<0.01), corneal nerve branch density and fiber length increased (p≤0.01), vibration perception improved (p<0.01), and DN4 and sudomotor function showed no change. There was no association between the change in CCM measures with change in HbA1c, weight or lipids.ConclusionsTreatment with exenatide and pioglitazone or basal-bolus insulin results in corneal nerve regeneration, but no change in neuropathic symptoms or sudomotor function over 1 year.

Aim: To examine the long-term efficacy of thiazolidinedione plus a glucagon-like peptide-1 receptor agonist versus basal-bolus insulin on glycaemic control and beta-cell function in patients with poorly controlled type 2 diabetes (T2D) on metformin plus sulphonylurea. Materials and Methods: Three hundred and thirty-one patients with poorly controlled T2D were recruited over 3 years and were followed for an additional year. Subjects received a 75 g oral glucose tolerance test (OGTT) at baseline and at study end. After completing the baseline OGTT, subjects were randomized to receive either pioglitazone plus weekly exenatide (combination therapy) or basal/bolus insulin (insulin therapy) to maintain an HbA1c of less than 7.0%. The primary outcome of the study was the difference in HbA1c at study end between the two treatment groups. Results: Both therapies caused a robust decrease in HbA1c. However, combination therapy caused a greater decrement (−1.1%, P < .0001) than insulin therapy, and more subjects in the combination therapy group (86%) achieved the American Diabetes Association goal of glycaemic control (HbA1c < 7.0%) than those in the insulin therapy group (44%) (P < .0001). Both therapies improved insulin secretion. However, the improvement in insulin secretion with combination therapy was 2.5-fold greater (P < .001) than with insulin therapy (50%). Insulin therapy caused more weight gain and hypoglycaemia. Conclusion: Both combination therapy and insulin therapy effectively reduced HbA1c in poorly controlled T2D on multiple oral agents. However, combination therapy produced a greater improvement in insulin secretion and decrease in HbA1c with a lower risk of hypoglycaemia.

Exenatide/pioglitazone combination therapy is an effective and safe therapeutic option in patients with poorly controlled T2DM receiving metformin plus sulfonylurea with very high HbA1c (>10%).

Aims/Introduction: Painful diabetic peripheral neuropathy (pDPN) is associated with small nerve fiber degeneration and regeneration. This study investigated whether the presence of pDPN might influence nerve regeneration in patients with type 2 diabetes undergoing intensive glycemic control. Materials and Methods: This exploratory substudy of an open-label randomized controlled trial undertook the Douleur Neuropathique en 4 questionnaire and assessment of electrochemical skin conductance, vibration perception threshold and corneal nerve morphology using corneal confocal microscopy in participants with and without pDPN treated with exenatide and pioglitazone or basal-bolus insulin at baseline and 1-year follow up, and 18 controls at baseline only.Results: Participants with type 2 diabetes, with (n = 13) and without (n = 28) pDPN had comparable corneal nerve fiber measures, electrochemical skin conductance and vibration perception threshold at baseline, and pDPN was not associated with the severity of DPN. There was a significant glycated hemoglobin reduction (P < 0.0001) and weight gain (P < 0.005), irrespective of therapy. Participants with pDPN showed a significant increase in corneal nerve fiber density (P < 0.05), length (P < 0.0001) and branch density (P < 0.005), and a decrease in the Douleur Neuropathique en 4 score (P < 0.01), but no change in electrochemical skin conductance or vibration perception threshold. Participants without pDPN showed a significant increase in corneal nerve branch density (P < 0.01) and no change in any other neuropathy measures. A change in the severity of painful symptoms was not associated with corneal nerve regeneration and medication for pain. Conclusions: This study showed that intensive glycemic control is associated with greater corneal nerve regeneration and an improvement in the severity of pain in patients with painful diabetic neuropathy.