Introduction
Semglee (insulin glargine-yfgn) is a long-acting basal insulin analog biosimilar to Lantus (insulin glargine). Approved by the FDA in 2020, it represents the first "interchangeable" biosimilar insulin product, meaning it can be substituted for the reference product at the pharmacy level without prescriber intervention. Semglee provides basal glycemic control for patients with diabetes mellitus.
Mechanism of Action
Semglee works through the same mechanism as endogenous insulin and other insulin analogs. It regulates glucose metabolism by stimulating peripheral glucose uptake, particularly in skeletal muscle and adipose tissue, and inhibiting hepatic glucose production. Insulin glargine-yfgn forms microprecipitates in the subcutaneous tissue after injection, resulting in a slow, consistent release of insulin into the bloodstream that provides a prolonged duration of action (up to 24 hours or longer) with no pronounced peak.
Indications
- Treatment of type 1 diabetes mellitus in adults and pediatric patients
- Treatment of type 2 diabetes mellitus in adults
- May be used alone or in combination with oral antidiabetic agents or rapid-acting insulins
Dosage and Administration
Dosing: Individualized based on patient's metabolic needs, blood glucose monitoring results, and glycemic control goals Route: Subcutaneous injection only Standard administration:- Typically administered once daily at the same time each day
- Rotate injection sites (abdomen, thigh, or upper arm) to reduce lipodystrophy risk
- Available in 100 units/mL concentration in 10 mL vials and 3 mL prefilled pens
- Renal impairment: Requires careful glucose monitoring and dose adjustment
- Hepatic impairment: Requires careful glucose monitoring and dose adjustment
- Elderly: May require more conservative dosing due to increased hypoglycemia risk
- Pediatrics: Safety and effectiveness established for children ≥6 years with type 1 diabetes
Pharmacokinetics
Absorption: Slowly absorbed from subcutaneous injection site with onset of action within 2-4 hours Distribution: Binds to insulin receptors throughout the body Metabolism: Metabolized primarily in the liver and kidney to active and inactive metabolites Elimination: Half-life approximately 12 hours; duration of action up to 24 hours Time to peak effect: No pronounced peak; relatively constant activity profileContraindications
- Hypersensitivity to insulin glargine-yfgn or any excipients
- During episodes of hypoglycemia
- Hypersensitivity reactions to previous insulin glargine products
Warnings and Precautions
Hypoglycemia: Most common adverse reaction; may be severe and life-threatening Hypokalemia: Insulin preparations can cause hypokalemia, which may be life-threatening Allergic reactions: Severe, life-threatening allergic reactions may occur Fluid retention and heart failure: May occur with concomitant use of thiazolidinediones Lipodystrophy: May occur at injection site; rotate injection sites Weight gain: Can occur with insulin therapy Medication errors: Accidental mix-ups between insulin products can occurDrug Interactions
Drugs that may increase hypoglycemia risk:- Oral antidiabetic agents
- ACE inhibitors
- Disopyramide
- Fluoxetine
- MAO inhibitors
- Pentoxifylline
- Propoxyphene
- Salicylates
- Somatostatin analogs
- Sulfonamide antibiotics
- Corticosteroids
- Danazol
- Diuretics
- Estrogens
- Glucagon
- Isoniazid
- Niacin
- Phenothiazines
- Protease inhibitors
- Somatropin
- Sympathomimetic agents
- Thyroid hormones
Adverse Effects
Common adverse reactions (≥5%):- Hypoglycemia
- Allergic reactions
- Injection site reactions
- Lipodystrophy
- Weight gain
- Peripheral edema
- Severe hypoglycemia
- Hypokalemia
- Severe allergic reactions (anaphylaxis)
- Fluid retention and heart failure
Monitoring Parameters
- Blood glucose levels (fasting and postprandial)
- HbA1c every 3 months until stabilized, then every 6 months
- Signs and symptoms of hypoglycemia
- Injection sites for reactions or lipodystrophy
- Serum potassium in patients at risk for hypokalemia
- Weight changes
- Signs of fluid retention or heart failure
- Renal and hepatic function periodically
Patient Education
- Never share insulin pens or needles with others
- Proper injection technique and site rotation
- Recognition and management of hypoglycemia symptoms
- Importance of consistent meal patterns and timing of injections
- Need for regular blood glucose monitoring
- How to handle missed doses (do not double dose)
- Proper storage (refrigerate unopened; may be stored at room temperature after opening)
- Always have a source of glucose available for hypoglycemia treatment
- Inform healthcare providers of all medications being taken
- Carry diabetes identification
- Travel considerations for insulin storage and timing across time zones
References
1. FDA Approval: Semglee (insulin glargine-yfgn) injection. FDA News Release. July 28, 2020. 2. Semglee [package insert]. Princeton, NJ: Sandoz Inc; 2021. 3. Rosenstock J, et al. Adv Ther. 2021;38(5):2452-2464. 4. American Diabetes Association. Standards of Medical Care in Diabetes—2023. Diabetes Care. 2023;46(Suppl 1):S1-S291. 5. Home PD. The pharmacokinetics and pharmacodynamics of rapid-acting insulin analogues and their clinical consequences. Diabetes Obes Metab. 2012;14(9):780-788. 6. Heinemann L, et al. Biosimilar insulins: basic considerations. J Diabetes Sci Technol. 2014;8(1):6-13.