The State of GLP-1 in 2026
Two years after semaglutide and tirzepatide went mainstream, the GLP-1 landscape has evolved dramatically. Here's what's changed.
What's New Since 2024
Retatrutide Enters Phase III
Eli Lilly's triple agonist (GIP + GLP-1 + Glucagon) produced 24.2% weight loss in Phase II — approaching bariatric surgery territory from a weekly injection. The TRIUMPH Phase III program is now fully enrolled.
Oral GLP-1 Agents
Orforglipron (Eli Lilly) showed ~15% weight loss as an oral pill in Phase II. If confirmed in Phase III, this eliminates the injection barrier entirely. Multiple other oral candidates are in development.
Muscle Preservation Solutions
The 30-40% lean mass loss problem is being addressed:
- Bimagrumab + semaglutide trials show preserved muscle mass
- High-protein protocols (1.6g/kg) reduce lean mass loss significantly
- Resistance training is now considered mandatory alongside GLP-1 therapy
Practical Guidance for 2026
If You're Considering a GLP-1 Agonist
- Get baseline labs: HbA1c, fasting insulin, lipid panel, body composition
- Commit to resistance training 3-4x/week BEFORE starting
- Set protein intake at 1.2-1.6g per pound of goal body weight
- Start at lowest dose and titrate slowly (reduces GI side effects)
- Plan for the long haul — stopping leads to weight regain without lifestyle changes
Semaglutide vs Tirzepatide: The 2026 Decision
- Semaglutide: More long-term data, proven cardiovascular benefits (SELECT), wider insurance coverage
- Tirzepatide: Greater weight loss potential, better metabolic improvements, less long-term data
- Both: Effective, well-tolerated, require lifestyle commitment
What We're Watching
- Retatrutide Phase III results (expected 2026-2027)
- Orforglipron Phase III (oral GLP-1)
- CagriSema (semaglutide + amylin analog)
- Long-term cardiovascular outcomes for tirzepatide
- Alzheimer's trials for semaglutide (EVOKE)
The GLP-1 class is arguably the most important pharmaceutical development since statins. We'll continue covering every meaningful update.