Semaglutide is the active ingredient behind two of the most talked-about medications in Australia: Wegovy (for weight loss) and Ozempic (for diabetes). Understanding this molecule helps you navigate the confusing landscape of brand names, approvals, and restrictions.
What is semaglutide?
Semaglutide is a synthetic version of GLP-1 — a gut hormone that regulates appetite, digestion, and blood sugar. Developed by Danish pharmaceutical company Novo Nordisk, it was first approved for diabetes (as Ozempic) in 2017, then for weight loss (as Wegovy) at a higher dose in 2024 in Australia.
The same molecule, at different doses, for different conditions:
| Ozempic | Wegovy | |
|---|---|---|
| Dose | Up to 1mg/week | Up to 2.4mg/week |
| Approved for | Type 2 diabetes | Weight management |
| PBS | Yes (diabetes) | Pending |
| Cost | $41 PBS / $130–190 private | $400–$460 private |
| Available for weight loss? | Restricted | Yes |
How effective is semaglutide for weight loss?
The STEP clinical trial programme — involving over 15,000 participants — showed that semaglutide 2.4mg (Wegovy) produces an average 14.9% body weight loss over 68 weeks. About one-third of participants lost 20% or more. The SELECT trial further showed a 20% reduction in cardiovascular events (heart attacks, strokes) — making semaglutide the first weight loss drug proven to protect heart health.
Semaglutide vs tirzepatide
The main competitor to semaglutide is tirzepatide (Mounjaro), which targets an additional receptor (GIP) alongside GLP-1. Cross-trial comparisons suggest tirzepatide produces approximately 4–6 percentage points more weight loss (~21% vs ~15-17%). However, semaglutide has more extensive safety data and the cardiovascular outcomes evidence.
Semaglutide vs tirzepatide deep dive →
The future of semaglutide in Australia
- PBS listing: Pending for Wegovy (BMI ≥35 + CVD). Would reduce cost to ~$31.60/script.
- Oral version: Launched in the US as a daily pill. Australian availability estimated 2027–2028.
- Higher doses: Novo Nordisk is testing semaglutide at even higher doses (up to 7.2mg) in the STEP UP trials, showing potentially greater weight loss.