Inzolfi (Fingolimod)

Inzolfi (fingolimod) acts on the sphingosine‑1‑phosphate receptor pathway to modify disease activity in multiple sclerosis.

• Relapsing‑remitting multiple sclerosis: reduces annualized relapse rate and delays disability accumulation.
• Secondary progressive multiple sclerosis with active disease: decreases risk of confirmed disability progression.
• Clinically isolated syndrome at high risk of conversion: may postpone development of definite multiple sclerosis.

• Fingolimod is a structural analogue of sphingosine that binds to sphingosine‑1‑phosphate (S1P) receptors 1, 3, 4 and 5 on lymphocytes. By functionally antagonising S1P1, it prevents lymphocyte egress from lymph nodes, lowering circulating autoreactive T cells and thereby reducing neuroinflammation within the central nervous system. The drug’s selective modulation also influences endothelial barrier integrity and may affect astrocyte activity, contributing further to its therapeutic effect.

Fingolimod may cause a range of adverse reactions, which are categorized by frequency and severity.

Common Side Effects

• Headache: mild to moderate pain often occurring early in treatment.
• Nasopharyngitis: upper respiratory tract infection symptoms such as sore throat and runny nose.
• Diarrhea: loose stools that may be self‑limiting.
• Fatigue: persistent tiredness affecting daily activities.

Serious or Rare Side Effects

• Infections: including herpes zoster and opportunistic infections.
• Cardiac events: bradyarrhythmia or atrioventricular block, especially after first dose.
• Macular edema: swelling of the central retina that can impair vision.
• Severe liver injury: marked elevation of transaminases or hepatic failure.

Before initiating fingolimod therapy, several precautionary measures should be observed to ensure patient safety.

• Baseline cardiac assessment: obtain ECG and monitor heart rate during first dose.
• Liver function monitoring: check ALT/AST levels before start and periodically thereafter.
• Vaccination status: avoid live vaccines while on treatment and update inactivated vaccines as recommended.
• Infection screening: treat active infections and assess risk of latent infections such as tuberculosis.
• Pregnancy and breastfeeding: discuss potential risks with a healthcare professional before use.
• Store at ambient temperature: keep below 25 °C in the original packaging, protect from moisture and light.

Fingolimod can interact with other medicines, altering its efficacy or safety profile.

Major Interactions (Avoid)

• Strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole): increase fingolimod exposure and risk of toxicity.
• Strong CYP3A4 inducers (e.g., rifampicin, carbamazepine): reduce fingolimod levels and may diminish therapeutic effect.
• Live vaccines: may cause severe infection due to immunosuppression.

Moderate Interactions (Monitor Closely)

• Moderate CYP3A4 inhibitors (e.g., erythromycin): may modestly raise fingolimod concentrations.
• Antihypertensive agents (e.g., beta‑blockers): can exacerbate bradycardia when combined with first‑dose monitoring.
• Other immunosuppressants (e.g., azathioprine): increase overall risk of infection.