Fingolimod: S1P modulator in relapsing-remitting MS
Fingolimod (brand name Gilenya) was the first orally available disease-modifying substance in relapsing-remitting multiple sclerosis (RRMS), approved in the USA in 2010 and in the EU in 2011. It belongs to the class of sphingosine 1 phosphate receptor modulators (S1P modulators). Its launch began a new era of oral MS therapy, since extended by dimethyl fumarate, teriflunomide, ozanimod, ponesimod and cladribine.
Fingolimod is a prodrug from the fungus Isaria sinclairii. After phosphorylation by sphingosine kinase 2, the active metabolite fingolimod phosphate is formed, binding with high affinity to S1P receptor subtypes 1, 3, 4 and 5. Therapeutically decisive is modulation of the S1P1 receptor on lymphocytes.
Mechanism of action
Lymphocytes leave lymph nodes pulled by an S1P concentration gradient into the blood. The S1P1 receptor on lymphocytes is required for this. Fingolimod phosphate binds to S1P1, leading to internalisation and subsequent degradation of the receptor. Without functional S1P1, naive and central memory lymphocytes remain in the lymph nodes and can no longer migrate into the CNS.
The result is a reduction of circulating lymphocytes by about 70 % and markedly decreased lymphocyte infiltration into the CNS. Effector memory lymphocytes important for fighting acute infection remain largely unaffected.
Modulation of S1P3 receptors on the heart explains the initial bradycardia and AV conduction delay. Modulation at endothelial cells can increase the risk of macular oedema.
Indications
- Relapsing-remitting multiple sclerosis (RRMS): highly active form in adults and, since 2018, also in children and adolescents from 10 years
- Secondary progressive MS with superimposed relapses: off-label, since newer S1P modulators are partly specifically approved
Fingolimod is not approved in primary progressive MS and not in combination with other disease-modifying therapies.
Dosing and administration
Standard adult dose: 0.5 mg once daily orally, regardless of meals.
Children and adolescents below 40 kg: 0.25 mg once daily.
First dose monitoring: due to initial bradycardia and possible AV blocks, 6 hours of clinical observation after the first dose are mandatory. Required:
- ECG before first administration
- Blood pressure and pulse before and hourly after the dose
- ECG after 6 hours; with abnormalities prolonged monitoring
- In high-risk patients, 24-hour monitoring is recommended
If therapy is interrupted for more than 14 days, first-dose monitoring is required again on resumption.
Side effects
Very common: headache, lymphopenia, influenza-like illness, diarrhoea, cough, raised liver transaminases, back pain.
Common: sinusitis, bradycardia, first-degree AV block, hypertension, dyspnoea, respiratory tract infections, eczema, pruritus, tinea infections.
Uncommon: macular oedema (especially in the first treatment year), pneumonia, haemolytic anaemia, thrombocytopenia, seizures, posterior reversible encephalopathy syndrome (PRES).
Rare and very rare: progressive multifocal leukoencephalopathy (PML), cryptococcal meningitis, skin malignancies (basal cell carcinoma, squamous cell carcinoma, melanoma), lymphomas, severe hepatitis, atypical rebound activity after discontinuation with massive MS relapses.
Important safety aspects:
- First-dose monitoring is mandatory; clarify cardiac risk profile beforehand
- Ophthalmologic examination after 3 to 4 months to detect macular oedema, especially in diabetics or with uveitis history
- Regular monitoring of lymphocyte count; with values below 200 per microlitre, pause therapy
- Annual skin checks because of increased skin malignancy risk
- Suspected PML: immediate MRI and CSF PCR for JC virus
- Before therapy clarify varicella status; vaccinate at least 1 month before starting if needed
Interactions
- Other immunosuppressive therapies: additive immunosuppression, combination mostly contraindicated
- QT-prolonging substances, class Ia or III antiarrhythmics: additive effect, ECG checks
- Beta-blockers, calcium channel blockers (verapamil, diltiazem): additive bradycardia
- Live vaccines: contraindicated during and 2 months after therapy
- Strong CYP3A4 inhibitors and inducers: possible level changes
- Ketoconazole: moderate level increase
Special considerations
Pregnancy: contraindicated due to teratogenic risk. Women of childbearing potential must use reliable contraception during therapy and at least 2 months after stopping.
Breastfeeding: contraindicated.
Before starting therapy: ECG, blood pressure, liver values, full blood count, lymphocyte count, varicella antibodies, JC virus status, ophthalmologic and dermatologic examination, MS-specific MRI.
Stopping therapy: after discontinuation, rebound activity with massive MS relapses can occur, often more severe than before therapy. Careful planning of follow-up therapy is therefore essential.
Overview of S1P modulators: ozanimod and ponesimod have a slightly more favourable profile compared with fingolimod regarding initial bradycardia and selectivity, but have less long-term experience. The choice is individual.
Quality of life: for many MS patients the once-daily tablet is a clear relief compared with injection therapies (glatiramer acetate, interferons). The first-dose monitoring is a one-time organisational hurdle, routinely managed in specialised centres.
Related substances
- Dimethyl fumarate, oral immunomodulator in RRMS
- Glatiramer acetate, injectable immunomodulator
- Inebilizumab, anti-CD19 antibody in NMOSD
- Methotrexate, alternative immunosuppression
Frequently asked questions
Why is the first dose required in hospital?
Fingolimod can cause a transient drop in heart rate and occasional AV blocks at the first dose. Since the risk is greatest in the first 6 hours, the first dose is given under ECG and blood pressure monitoring. This allows early detection and treatment of relevant reactions.
What about pregnancy plans?
Anyone planning pregnancy must stop fingolimod and observe at least 2 months washout. Rebound can occur during the wash-out, hence the follow-up strategy is planned carefully in advance. Often a switch to a more pregnancy-compatible therapy is made.
How high is the PML risk?
PML on fingolimod is much rarer than on natalizumab, but documented. Risk factors are long therapy duration, low lymphocyte counts and high JC virus antibody titres. Close monitoring and regular MRI are sensible.
What happens on discontinuation?
After stopping, rebound with marked relapses can occur, often 2 to 6 months after the end of therapy. The follow-up therapy is therefore planned carefully, ideally with a timely switch to another disease-modifying substance.
Sources
- EMA Gilenya (fingolimod) EPAR
- BfArM Federal Institute for Drugs and Medical Devices
- AWMF multiple sclerosis guideline
- Gelbe Liste fingolimod monograph
Legal notice and disclaimer
The information on this page is provided for general information purposes only and does not constitute medical advice, diagnosis or treatment recommendation. It does not replace the advice of a licensed physician or pharmacist. Medicines should only be used after a doctor's prescription or pharmacy supply. All information is based on summaries of product characteristics and accepted scientific sources at the time of writing; the current SmPC of the manufacturer is always decisive. Sanoliste accepts no liability for completeness, timeliness or accuracy. In a medical emergency, dial the emergency number 112.