Psoriasis Drug Alefacept Shows Promise in Treating Diabetes
Targeting memory T cells might be useful strategy, authors say (September 23)
A drug formerly used to treat psoriasis has shown encouraging results in a phase II trial to assess its effectiveness in patients with type 1 diabetes, according to new research published in Lancet Diabetes and Endocrinology.
Alefacept has been used for about a decade to treat psoriasis, which is thought to be an autoimmune disorder. Results from clinical trials in psoriasis have shown that the drug works by attacking specific types of T cells that are involved in the body’s autoimmune response.
Since type 1 diabetes involves the same T cells attacking insulin-producing cells in the pancreas, researchers at Indiana University and the Riley Hospital for Children in Indianapolis investigated whether alefacept had an effect on patients with newly diagnosed type 1 diabetes.
In the new study, 33 subjects received weekly injections of alefacept for 12 weeks, followed by a break of 12 weeks, and then 12 further weekly doses. Sixteen additional subjects received placebo according to the same schedule.
The trial’s primary outcome was a measure of how well the pancreas could secrete insulin in response to food 2 hours after eating. The researchers found no significant difference between the two groups according to this measure, but there were some notable differences between the groups when secondary outcomes were analyzed. Using the same measure of insulin secretion 4 hours after eating, there was a significant difference between the study and control group: the group that received alefacept showed preserved insulin secretion, whereas insulin secretion in the placebo group decreased.
Moreover, 12 months after starting treatment, insulin use in the placebo group was significantly higher than in the study group. Moreover, those who received alefacept showed no significant increase in insulin use over the course of the trial, whereas those in the placebo group did. These results suggest that treatment with alefacept preserved the body’s ability to produce its own insulin. Participants receiving alefacept also had fewer episodes of hypoglycemia.
Importantly, alefacept was found to deplete potentially disease-causing T cells while leaving protective regulatory T cells unaffected.