Is Vyepti (Eptinezumab) 300 milligrams every 3 months for 4 visits medically necessary for a patient with spasmodic torticollis (G24.3)?

Medical Necessity Assessment: Vyepti for Spasmodic Torticollis

Vyepti (eptinezumab) 300 mg every 3 months for 4 visits is NOT medically necessary for spasmodic torticollis (G24.3), as this medication is FDA-approved exclusively for migraine prevention and has no established role in treating cervical dystonia.

Indication Mismatch

• Vyepti is a CGRP (calcitonin gene-related peptide) antagonist specifically approved for prevention of episodic or chronic migraine, not for movement disorders or dystonia 1
• The 2024 VA/DoD Headache Guidelines suggest intravenous eptinezumab for migraine prevention, with demonstrated reduction in mean monthly migraine days, particularly at the 300 mg dose 1
• There is no evidence base, clinical rationale, or FDA approval for using eptinezumab in spasmodic torticollis 1

Evidence-Based Treatment for Spasmodic Torticollis

First-Line Therapy: Botulinum Toxin

Botulinum toxin injections are the established standard of care for spasmodic torticollis (cervical dystonia), not CGRP antagonists 1:

• The American Academy of Otolaryngology-Head and Neck Surgery recommends botulinum toxin injections for treatment of focal dystonia based on randomized controlled trials with preponderance of benefit over harm 1
• Botulinum toxin provides excellent symptom control for 3 to 6 months by causing transient flaccid paralysis of dystonic muscles through inhibition of acetylcholine release 1
• Clinical studies demonstrate 62-86% of patients with spasmodic torticollis experience significant improvement in head posture with botulinum toxin 2, 3
• Injections are typically repeated every 3-4 months into affected muscles (most commonly sternocleidomastoid, trapezius, and splenius capitis) 2, 3

Dosing and Administration

• Optimal doses range between 200-400 mouse units per muscle for cervical dystonia 3
• Treatment can be performed in outpatient settings with minimal discomfort 1
• 84% of patients with pain associated with torticollis experience relief following botulinum toxin injection 3

Safety Profile

• Transient dysphagia occurs in 22% of treatment sessions and mild neck weakness in 10% 3
• These adverse effects are temporary and resolve spontaneously 3, 4
• The treatment is considered safe for long-term management 2, 3, 5

Critical Distinction

The diagnosis code G24.3 (spasmodic torticollis) represents a movement disorder characterized by involuntary neck muscle contractions causing abnormal head positioning—this is fundamentally different from migraine headache 1:

• Spasmodic torticollis is a focal dystonia affecting cervical musculature 1
• Migraine is a neurovascular headache disorder involving CGRP pathways 1
• These are distinct pathophysiologic entities requiring different therapeutic approaches

Recommendation

Medical necessity is NOT met for Vyepti in this case. The appropriate evidence-based treatment for spasmodic torticollis is botulinum toxin injection into affected cervical muscles every 3-4 months 1, 2, 3. If the patient has not yet tried botulinum toxin therapy, this should be initiated as first-line treatment. If botulinum toxin has failed or is contraindicated, alternative therapies for dystonia should be considered—but CGRP antagonists like Vyepti have no role in cervical dystonia management based on current evidence and FDA indications.