Liraglutide (Saxenda)

Liraglutide (Saxenda) holds a singular place in the history of obesity pharmacology: it was the first GLP-1 receptor agonist approved specifically for chronic weight management, receiving FDA clearance in December 2014 — nearly seven years before semaglutide's obesity approval and nearly nine years before tirzepatide. A daily subcutaneous injection, liraglutide works through GLP-1 receptor agonism to reduce appetite and slow gastric emptying, the same fundamental mechanism as all later agents in this class. The pivotal SCALE trials established its efficacy: approximately 8 percent body weight reduction versus 2 to 3 percent for placebo at 56 weeks, with 3-year long-term follow-up data providing what remains one of the longest clinical evidence bases in the class. Over a decade of real-world post-market use has produced an extensive safety database — particularly reassuring for the rare but serious concerns (pancreatitis, thyroid effects) that are common questions for all GLP-1 drugs. Liraglutide's 3-year SCALE data also showed durable weight maintenance with continued use, though weight returns after discontinuation similarly to other agents. The primary clinical limitation in 2026 is competitive: the newer once-weekly agents (semaglutide, tirzepatide) produce 14.9 to 20.9 percent weight loss versus liraglutide's approximately 8 percent, and require only one injection per week versus Saxenda's daily dosing. The daily injection burden is a meaningful adherence challenge. However, Saxenda remains relevant for patients who have previously tolerated it well, those whose insurance covers it but not newer agents, and patients who prefer a well-established drug with the longest real-world experience of any GLP-1 obesity medication. Cost has come down modestly with generic competition pending.