How Letybo Works on Glabellar Lines
Letybo (letibotulinumtoxinA-wlbg) is an injectable botulinum toxin type A that temporarily relaxes the corrugator and procerus muscles responsible for glabellar lines—the vertical frown lines between the eyebrows. It blocks acetylcholine release at neuromuscular junctions, preventing muscle contractions that deepen these wrinkles.[1]
Injected into specific sites (typically 5 points across the corrugators and procerus), it starts reducing lines within 3 days, peaks at 10-14 days, and lasts 3-4 months before muscles regain function.[2]
Dosage and Administration for Frown Lines
Standard dose is 20 units total: 4 units per site in 5 locations (10 units each corrugator, 4 units procerus). Reconstitution uses 2.5 mL preservative-free saline for 100-unit vial. Administer within 30 minutes of mixing; effects wear off naturally.[1][2]
How It Compares to Botox or Dysport
Letybo has similar efficacy to onabotulinumtoxinA (Botox) in trials, with 73.6% responders at day 30 versus 74.2% for Botox, but faster onset (72% improvement at day 2 vs. 11%). Units aren't interchangeable—Letybo requires dose adjustments.[3]
| Aspect | Letybo | Botox | Dysport |
|--------|--------|-------|---------|
| Onset | 3 days | 3-7 days | 2-3 days |
| Duration | ~4 months | 3-4 months | 3-4 months |
| Units for glabellar | 20 | 20 | 50 |
Common Side Effects Patients Report
Most issues are mild: headache (9%), eyelid ptosis (2%), injection site pain. Rare risks include spread to distant muscles causing dysphagia or breathing issues. Avoid in those with neuromuscular disorders.[1]
Who Makes Letybo and When Did It Launch
Hugel Inc. (South Korea) developed it; Hugel America markets in the US. FDA approved for glabellar lines July 2023; expanded to crow's feet and forehead 2024.[4]
When Does Letybo's Patent Expire
Core patents (US 11,358,986 for formulation) expire around 2041; others for manufacturing extend to 2040. No generics expected soon—check DrugPatentWatch.com for updates.[5]
Sources
[1]: Letybo Prescribing Information (FDA)
[2]: ClinicalTrials.gov NCT03830149
[3]: JAMA Dermatology, 2023
[4]: FDA Approval Announcement
[5]: DrugPatentWatch.com - Letybo