Symlin

Symlin Pramlintide injection

AMYLIN PHARMACEUTICALSAmylin analog approved for type 2 and 1 diabetes
This synthetic analog of human amylin affects the rate of postprandial glucose appearance by slowing gastric emptying, suppressing glucagon secretion, and regulating food intake through centrally mediated modulation of appetite. Pramlintide was approved on March 16, 2005, for use in conjunction with insulin to treat type 2 and type 1 diabetes in patients who have failed to achieve desired glucose control despite optimal insulin therapy.

Efficacy. The efficacy of pramlintide was evaluated in several clinical trials that included a total of 1,688 patients with type 2 diabetes and 2,375 patients with type 1 diabetes. In 2 long-term (26–52 wk), randomized, double-blind, placebo-controlled studies, 120 µg of pramlintide administered prior to major meals was evaluated in patients with type 2 diabetes using fixed-dose insulin. Patients receiving placebo with their fixed-dose insulin experienced a change in HbA1c at 6 months relative to baseline of –0.17% compared with a –0.57% change in patients receiving pramlintide (P<.05). Patients receiving placebo experienced a +0.2-kg change in weight at 6 months relative to baseline compared with a –1.5-kg change in patients receiving pramlintide (P<.05). The percent changes in rapid/short-acting insulin doses and long-acting insulin doses at 6 months in the placebo group were +6.5 and +5.2, respectively. This is compared to percent changes of –3.0 and –0.2 in the doses of rapid/short-acting insulin and long-acting insulin, respectively, in the pramlintide group (P<.05). In 3 long-term (26–52 wk), randomized, double-blind, placebo-controlled studies, 30 or 60 µg of pramlintide administered prior to major meals was evaluated in patients with type 1 diabetes. Patients receiving placebo with their fixed-dose insulin experienced a change in HbA1c at 6 months relative to baseline of –0.10% compared with a –0.43% change in patients receiving pramlintide (P<.05). Patients receiving placebo experienced a +0.6-kg change in weight at 6 months relative to baseline compared with a –1.1-kg change in patients receiving pramlintide (P<.05).

Dosing. Pramlintide should be administered immediately prior to major meals as a subcutaneous (SC) injection in either the thigh or abdomen, with injection sites being rotated so that the same site is not used repeatedly. In patients with type 2 diabetes, pramlintide should be initiated at a dose of 60 µg and increased to 120 µg as tolerated. In patients with type 1 diabetes, pramlintide should be initiated at a dose of 15 µg and titrated at 15-µg increments to a maintenance dose of 30 or 60 µg as tolerated. Tolerance is indicated by the absence of any clinically significant nausea for at least 3 days in both diabetes patient populations. Preprandial, rapid/short-acting insulin dosages should be reduced by 50% when initiating pramlintide therapy in both diabetes patient populations. Under the direction of a health-care professional, the insulin dose may be adjusted to optimize glycemic control after the target dose of pramlintide is achieved and tolerated.

Availability. According to the manufacturer, pramlintide will be available approximately 90 days from the approval date (mid-June 2005).