BACKGROUND: Amylin is a hormone cosecreted with insulin by the beta cells of the pancreas. It suppresses postprandial glucagon secretion and slows gastric emptying. Pramlintide acetate is an amylin analogue that was approved by the US Food and Drug Administration in March 2005.
OBJECTIVE: This article reviews the current primary literature on the clinical efficacy and tolerability of pramlintide injection in the treatment of type 1 and type 2 diabetes mellitus (DM). Among other topics covered are the pharmacokinetics, pharmacodynamics, and dosing and administration of pramlintide.
METHODS: Pertinent English-language articles were identified through a search of MEDLINE (1966-January 2007), International Pharmaceutical Abstracts (1970-present), Database of Abstracts of Reviews of Effectiveness (1995-January 2007), Cochrane Database of Systematic Reviews (1995-January 2007), and EMBASE Drugs & Pharmacology (1991-1st quarter 2007). The search terms included pramlintide, amylin, gastric emptying, pharmacokinetic, pharmacoeconomic, postprandial hyperglycemia, and glucagon. Articles were selected for review if they described studies having a randomized, double-blind, controlled design and included glycosylated hemoglobin (HbA(1c)) as an end point.
RESULTS: Pramlintide is administered subcutaneously in the abdominal area or thigh immediately before each main meal to achieve maximal reductions in post-prandial glucose excursions. Its C(max) is reached within 20 minutes, and its t(1/2) is 48 minutes. Metabolism is primarily via the kidneys. Pramlintide therapy was associated with inhibition of postprandial glucagon secretion in 24 patients with type 2 DM; prolonged gastric emptying in 11 patients with type 1 DM; a 23% reduction in total energy intake in 11 patients with type 2 DM; and a reduction in markers of oxidative stress in 18 patients with type 1 DM (all, P <- 0.05 vs placebo). In two 52-week studies in patients with type 1 DM, the groups that received pramlintide 30 to 60 microg QID (n = 243), 60 microg TID (n = 164), and 60 microg QID (n = 161) had respective 0.39%, 0.29%, and 0.34% reductions in HbA(1c) and 0.5-, 0.3-, and 0.6-kg reductions in body weight, respectively (all, P < 0.05 vs placebo). In two 52-week studies in patients with type 2 DM, the groups that received pramlintide 120 microg BID (n = 166) and 150 microg TID (n = 144) had respective 0.62% and 0.6% reductions in HbA(1c) and 1.4- and 1.3-kg reductions in body weight (all, P < 0.05 vs placebo). Hypoglycemia, nausea, vomiting, and anorexia were the most frequently reported (>/=10% occurrence) adverse events in patients receiving pramlintide compared with placebo. These events were mild to moderate and occurred more frequently during the first month of therapy.
CONCLUSIONS: Pramlintide therapy was associated with reductions in HbA(1c) and body weight in four 52-week studies in patients with type 1 DM and type 2 DM. Hypoglycemia, nausea, vomiting, and anorexia were the most frequently occurring adverse events, particularly during the first month of therapy. Pramlintide was associated with reductions in measures of oxidative stress, but studies are needed to evaluate the effects of this agent on DM-related complications.
