Natalizumab vs Fingolimod: side effects in FDA adverse event reports
At a glance
| Natalizumab | Fingolimod | |
|---|---|---|
| Drug class | Integrin Receptor Antagonist | – |
| Brand names | Tysabri | – |
| FAERS reports | 180,630 | 85,986 |
| Serious | 31% | 51% |
| Death outcome | 5,103 | 1,246 |
| Boxed warning | Yes PROGRESSIVE MULTIFOCAL LEUKOENCEPHALOPATHY TYSABRI increases the risk of progressive multifocal leukoencephalopathy (PML), an opportunistic viral infection of t | No |
Signals both drugs share
| Reaction | Natalizumab | Fingolimod | Label screen (A / B) |
|---|---|---|---|
| Multiple sclerosis relapse | 16,902 · PRR 37.4 | 7,732 · PRR 30.6 | Labeled (related wording) / Labeled (related wording) |
| Central nervous system lesion | 1,674 · PRR 15.9 | 2,900 · PRR 64.7 | Labeled (related wording) / Not in label — unassessed |
| Optic neuritis | 793 · PRR 11.0 | 747 · PRR 21.7 | Not in label — unassessed / Labeled (related wording) |
| Secondary progressive multiple sclerosis | 502 · PRR 41.6 | 291 · PRR 44.1 | Likely indication confounding / Likely indication confounding |
| Progressive multiple sclerosis | 233 · PRR 28.7 | 90 · PRR 20.2 | Likely indication confounding / Likely indication confounding |
| Band sensation | 220 · PRR 24.0 | 101 · PRR 20.9 | Not in label — unassessed / Not in label — unassessed |
| Relapsing-remitting multiple sclerosis | 110 · PRR 16.8 | 141 · PRR 47.5 | Likely indication confounding / Likely indication confounding |
Labeled signals distinctive to Natalizumab
- General symptom — n=2,192, PRR 47.4 Labeled (related wording)
- Progressive multifocal leukoencephalopathy — n=2,127, PRR 40.1 Labeled — boxed warning
- Musculoskeletal disorder — n=1,750, PRR 11.6 Labeled (related wording)
- Coordination abnormal — n=1,227, PRR 11.0 Labeled (related wording)
- Immune reconstitution inflammatory syndrome — n=1,182, PRR 35.7 Labeled adverse reaction
- Opportunistic infection — n=494, PRR 42.0 Labeled adverse reaction
- Infusion site bruising — n=202, PRR 12.1 Labeled (related wording)
- Multiple sclerosis pseudo relapse — n=57, PRR 24.1 Labeled (related wording)
Labeled signals distinctive to Fingolimod
- Lymphopenia — n=1,652, PRR 32.4 Labeled adverse reaction
- Macular oedema — n=863, PRR 44.4 Labeled adverse reaction
- Concomitant disease aggravated — n=463, PRR 19.7 Labeled (related wording)
- Atrioventricular block first degree — n=364, PRR 22.1 Labeled (related wording)
- Atrioventricular block second degree — n=240, PRR 20.8 Labeled (related wording)
- Tumefactive multiple sclerosis — n=99, PRR 338.9 Labeled adverse reaction
- Cryptococcal cutaneous infection — n=32, PRR 56.0 Labeled (related wording)
Common questions
Which has more reported side effects, Natalizumab or Fingolimod?
Natalizumab has 180,630 FAERS reports and Fingolimod 85,986. More reports does not mean more dangerous: volume follows how widely and how long a drug has been used, prescription vs over-the-counter status, and publicity. The seriousness share (31% vs 51%) is a better like-for-like signal of the kind of problems reported.
Which side effects do Natalizumab and Fingolimod share?
Both drugs carry disproportionality signals for multiple sclerosis relapse, central nervous system lesion, optic neuritis, secondary progressive multiple sclerosis, progressive multiple sclerosis. Shared signals often reflect a shared drug class or the condition both are used for.
Is Natalizumab or Fingolimod safer?
FAERS cannot answer that: it has no denominator and no comparator. Use this page to see which risks are already on each label and which signals are unlabeled, then check the prescribing information and your clinician for your situation.
Sources: openFDA FAERS pair statistics (OpenPV build 2026-09-14), FDA labels via openFDA, openFDA count queries for seriousness and deaths. Pair chosen because it is a commonly searched comparison. Generated 2026-10-08.