Generic Name

Ajovy®

Mechanism

• CGRP blockade – *Ajovy* binds to and neutralizes circulating CGRP, a neuropeptide that induces vasodilation and pain transmission in migraine.
• Prevents migraine initiation – By inhibiting CGRP signaling, the drug reduces the frequency and severity of migraine attacks without affecting other neurotransmitter systems or requiring acute treatment.

Pharmacokinetics

• Route – Subcutaneous (SC) injection.
• Absorption – Rapid, reaching peak serum concentrations ~1–2 days post‑dose.
• Distribution – Low volume of distribution (~5 L), largely confined to the vascular compartment.
• T½ – Mean terminal half‑life ≈ 27 days (range 22–34 days).
• Elimination – Linear, non‑enzymatic catabolism to peptides; no hepatic or renal drug‑drug interactions.
• Bioavailability – ~70 % SC relative to IV.
• Steady state – Achieved after 3–4 monthly administrations.

Indications

• Episodic migraine (≥4 ≤14 headache days/month).
• Chronic migraine (≥15 headache days/month, ≥8 migraine days).
• Adults 18 yrs and older.

Contraindications

• Hypersensitivity to galcanezumab or any excipient (e.g., polysorbate 80).
• Pregnancy – Category C; no safety data in humans; risk–benefit should be evaluated.
• Severe systemic disease (e.g., uncontrolled heart disease) – use with caution.
• Vaccination – Live vaccines should be avoided during treatment due to potential immune modulation; consult local guidelines.

Warnings
• Allergic reactions – Anaphylaxis, angioedema, or severe rash may occur (≈ 0.1 %).
• Injection site complications – Persistent pain, erythema, or abscess formation.
• No major drug interactions – Safe to co‑administer with most migraine prophylactics (beta‑blockers, topiramate, amitriptyline, etc.).

Dosing

• Administration technique
• Rotate injection sites (abdomen, thigh, upper arm).
• Clean with 70 % alcohol; allow to dry.
• Use the provided prefilled pen; inject at a 90° angle.
• Store at 2–8 °C; avoid freezing.

Missed dose – Administer as soon as possible; if >1 week late, restart at the loading dose.

Adverse Effects

Monitoring

• Baseline:
• Weight, blood pressure, basic metabolic panel (if other comorbidities).
• Review prior migraine prophylaxis and response.
• During therapy:
• Injection‑site assessment each visit.
• Monthly headache diary to evaluate efficacy (≥30 % reduction in headache days = success).
• Adverse effect screening (allergic reaction signs, infection).
• Immunogenicity – Rare; consider if loss of efficacy occurs.

Clinical Pearls

• CGRP‑Targeted Therapy is “Drug‑Naïve” – Patients who fail traditional prophylactics or cannot tolerate side effects often respond well to Ajovy without major drug‑drug interactions.
• Self‑Injection Training Improves Adherence – Demonstrating correct technique during first visit and providing a written step‑by‑step guide enhances compliance and reduces injection‑site complications.
• Pregnancy Precautions – Though no definitive teratogenic data, many neurologists opt for the lowest effective monthly dose and consider a washout period before conception.
• Combination Therapy is Safe – Ajovy can be concomitantly administered with beta‑blockers, antiepileptics, or antidepressants, offering additive prophylaxis for refractory migraine.
• Efficacy Persists Post‑Discontinuation – Some patients maintain reduced headache frequency up to 3 months after stopping the drug, suggesting a lasting neuromodulatory effect.
• Insurance Navigation – Many payers now allow direct‑to‑patient (D2P) ordering for monthly SC therapies, reducing pharmacy delays.
• Patient Education on “Missed Dose” – Explain the loading‑dose concept so patients understand why a higher initial dose is given to accelerate benefit.

In summary, *Ajovy* provides a targeted, well‑tolerated preventive option for migraine, especially valuable in patients who require a CGRP‑selective approach and in whom conventional prophylactics are unsuitable.