Sanofi-aventis announced that the results of the long-term, five-year study of Lantus (insulin glargine [rDNA] injection) versus NPH insulin on progression of retinopathy in patients with type-2 diabetes, published on-line in Diabetologia (DOI 10.1007/s00125-009-1415-7) showed similar effects on retinopathy and overall safety in the two treatment groups. This is the longest controlled study ever reported using insulin glargine.

Diabetic retinopathy is a major cause of blindness in patients with diabetes. It is a progressive disease that results from cellular proliferation within the eye. The stimulation of IGF1 receptors is involved in this process. In the study of patients with retinopathy, the progression of diabetic retinopathy was similar in the two treatment groups over the long-term course of treatment. This indicates that Lantus does not have mitogenic effects different from the human NPH insulin within "This five-year study is the longest randomized controlled study with insulin glargine versus NPH human insulin," said lead investigator Julio Rosenstock, director of the Dallas Diabetes and Endocrine Center at Medical City and also Clinical Professor of Medicine, University of Texas Southwestern Medical School. "This study demonstrated no evidence of a greater risk of progression of retinopathy with insulin glargine."

The five-year open-label study was specifically designed to further characterize the retinal safety profile of Lantus versus NPH in 1024 patients (Lantus once daily: 515 patients; NPH twice daily: 509 patients). Retinopathy progression was assessed using serial fundus photography. Progression was evaluated using the Early Treatment Diabetic Retinopathy Study (ETDRS) scale; the scores at study end were similar in both treatment groups (Lantus: 14.2 per cent, NPH: 15.7 per cent; 95 per cent CI: - 7.02, 3.06). As per protocol, the study aimed to achieve similar levels of glycaemia control in both groups, in order to avoid introducing bias on the primary retinopathy end-point that could be related to differences in blood glucose control. Both groups had comparable HbA1c at study end (mean HbA1c improved from a baseline of 8.4 and 8.3 per cent to 7.8 and 7.6 per cent for all patients in the insuline glargine and NPH insulin groups respectively). NPH insulin was associated with a significantly greater incidence of severe hypoglycaemia than was insulin glargine (11.1 vs 7.6 per cent respectively, p=0.0439) and mean yearly rates of symptomatic hypoglycaemia (7.08+/-16.49 vs 5.13+/-12.79, p=0.0017).

There was no observable trend for a difference in the incidence of serious adverse events including cancer, as well as adverse events leading to study withdrawal. The most common adverse events in the study were: upper respiratory tract infection (glargine 149 [29 per cent], NPH 169 [33.6 per cent]), peripheral edema (glargine 103 [20 per cent], NPH 114 [22.7 per cent]), and arthraralgia (glargine 73 [14.2 per cent], NPH 81 [16.1 per cent]).

Lantus is a truly 24-hour basal insulin without pronounced peak, and therefore efficaciously and safely lowers blood glucose.