Infliximab vs Natalizumab: side effects in FDA adverse event reports
At a glance
| Infliximab | Natalizumab | |
|---|---|---|
| Drug class | Tumor Necrosis Factor Blocker | Integrin Receptor Antagonist |
| Brand names | Renflexis | Tysabri |
| FAERS reports | 217,056 | 180,630 |
| Serious | 89% | 31% |
| Death outcome | 13,761 | 5,103 |
| Boxed warning | Yes SERIOUS INFECTIONS and MALIGNANCY WARNING: SERIOUS INFECTIONS and MALIGNANCY See full prescribing information for complete boxed warning. Increased risk of seri | Yes PROGRESSIVE MULTIFOCAL LEUKOENCEPHALOPATHY TYSABRI increases the risk of progressive multifocal leukoencephalopathy (PML), an opportunistic viral infection of t |
Signals both drugs share
No strong shared signal after removing coding and lab terms.
Labeled signals distinctive to Infliximab
- Lupus-like syndrome — n=3,336, PRR 56.5 Labeled adverse reaction
- Rheumatic fever — n=3,038, PRR 224.9 Labeled (related wording)
- Hepatosplenic t-cell lymphoma — n=184, PRR 94.3 Labeled — boxed warning
- Swollen joint count — n=135, PRR 117.9 Labeled (related wording)
Labeled signals distinctive to Natalizumab
- Multiple sclerosis relapse — n=16,902, PRR 37.4 Labeled (related wording)
- 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)
- Central nervous system lesion — n=1,674, PRR 15.9 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
Common questions
Which has more reported side effects, Infliximab or Natalizumab?
Infliximab has 217,056 FAERS reports and Natalizumab 180,630. 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 (89% vs 31%) is a better like-for-like signal of the kind of problems reported.
Which side effects do Infliximab and Natalizumab share?
They share no strong flagged signal after artifacts and lab terms are removed.
Is Infliximab or Natalizumab 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.