Overview

Albiglutide (marketed as Tanzeum/Eperzan) is a GLP-1 receptor agonist developed by GlaxoSmithKline and approved by the FDA in 2014 for the treatment of type 2 diabetes. It consists of two copies of a modified human GLP-1 (7-36) sequence with an alanine-to-glycine substitution at position 8 (conferring resistance to DPP-4 degradation), genetically fused to human albumin. This albumin fusion extends its plasma half-life to approximately 5 days, enabling once-weekly subcutaneous dosing.

In clinical trials within the HARMONY program, albiglutide demonstrated statistically significant reductions in HbA1c (typically 0.6-0.9%) compared to placebo, with modest weight loss effects. The HARMONY Outcomes trial notably demonstrated a significant 22% reduction in major adverse cardiovascular events (MACE) in patients with type 2 diabetes and established cardiovascular disease, establishing cardiovascular benefit for this drug class. Albiglutide was generally associated with less nausea and vomiting than shorter-acting GLP-1 receptor agonists, though injection site reactions were more common.

Despite its favorable cardiovascular profile, GlaxoSmithKline voluntarily withdrew albiglutide from the market in 2018 for commercial reasons, citing low uptake in an increasingly competitive GLP-1 receptor agonist landscape. Its clinical legacy persists through the HARMONY Outcomes data, which contributed to the broader understanding that GLP-1 receptor agonists as a class provide cardiovascular protection. Patients previously on albiglutide were typically transitioned to other agents such as dulaglutide or semaglutide.

Mechanism of Action

GLP-1 Receptor Agonism

Albiglutide is a long-acting glucagon-like peptide-1 (GLP-1) receptor agonist consisting of two tandem copies of a modified GLP-1(7-36) sequence fused to human albumin. The DPP-4 resistant Gly8 substitution and albumin fusion extend the half-life to approximately 5 days, enabling weekly dosing (PMID: 24463045).

Pancreatic Beta Cell Effects

Albiglutide binds the GLP-1 receptor (GLP-1R), a class B G-protein-coupled receptor on pancreatic β-cells. Gαs activation stimulates adenylyl cyclase → cAMP → PKA and Epac2 signaling. This potentiates glucose-stimulated insulin secretion (GSIS) by closing KATP channels, enhancing L-type Ca2+ channel activity, and mobilizing insulin granule exocytosis in a glucose-dependent manner (PMID: 17217214).

Beta Cell Survival and Proliferation

GLP-1R activation promotes β-cell survival through PI3K/Akt → CREB → IRS-2 signaling, upregulating anti-apoptotic Bcl-2 and Bcl-xL while suppressing pro-apoptotic Bax and caspase-3. It stimulates β-cell proliferation through TCF7L2-mediated Wnt signaling and cyclin D1 upregulation.

Glucagon Suppression

Albiglutide suppresses inappropriate glucagon secretion from pancreatic α-cells in a glucose-dependent manner. This is mediated both directly through GLP-1R on α-cells and indirectly via paracrine somatostatin release from δ-cells, reducing hepatic glucose output.

Gastric and Cardiovascular Effects

GLP-1R activation in gastric vagal afferents slows gastric emptying, contributing to postprandial glucose reduction and satiety. Cardiovascular GLP-1R signaling in cardiomyocytes enhances glucose uptake and has demonstrated a neutral-to-beneficial cardiovascular risk profile in the HARMONY Outcomes trial (PMID: 30291013).

Reconstitution Calculator

Research

Safety Profile

Safety Profile: Albiglutide (Tanzeum/Eperzan)

Note: Albiglutide was voluntarily withdrawn from the market in 2018 for commercial reasons, not safety concerns. The HARMONY Outcomes trial demonstrated cardiovascular benefit.

Common Side Effects

• GI effects (most common): Nausea (11%), diarrhea (13%), vomiting (5%) — typically transient, decreasing over weeks
• Injection site reactions: Nodules, erythema, pruritus at injection site (18%)
• Upper respiratory tract infections (14%)
• Headache, back pain, arthralgia

Serious Adverse Effects

• Boxed Warning (FDA): Thyroid C-cell tumors observed in rodents; contraindicated in patients with personal/family history of medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2)
• Pancreatitis: Acute pancreatitis reported; discontinue if suspected
• Hypoglycemia: Risk increased when combined with insulin or sulfonylureas
• Hypersensitivity: Anaphylaxis and angioedema reported rarely

Contraindications

• Personal or family history of MTC or MEN 2
• Prior serious hypersensitivity to albiglutide
• Pre-existing severe gastroparesis

Drug Interactions

• Insulin/sulfonylureas: Increased hypoglycemia risk — dose reduction of concomitant agents may be needed
• Oral medications: Delayed gastric emptying may affect absorption of co-administered oral drugs; monitor narrow therapeutic index drugs (e.g., warfarin)

Special Populations

• Pregnancy (Category C): Not recommended; discontinue at least 2 months before planned pregnancy (long half-life)
• Renal impairment: No dose adjustment needed; monitor for GI side effects that may worsen renal function (dehydration)
• Hepatic impairment: No dose adjustment studied; use with caution

Monitoring Recommendations

• Serum calcitonin if MTC symptoms arise (dysphagia, neck mass)
• Lipase/amylase if pancreatitis suspected
• HbA1c every 3 months; renal function periodically
• Injection site examination at follow-up visits

Reference: FDA Label (Tanzeum), NDA 125431

Pharmacokinetic Profile