Drug · FAERS side-effect profile with label screen
Ofatumumab side effects: what 33,036 FDA adverse event reports show
Drug class
CD20-directed Cytolytic Antibody
FDA label (Established Pharmacologic Class) · compare the class
Brand names
Kesimpta
openFDA label
Who reports
33,036 reports · 44% serious · 762 with death outcome · 74% female
openFDA FAERS counts, all years, deduplication not applied
Used for
KESIMPTA is indicated for the treatment of relapsing forms of multiple sclerosis (MS), to include clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease, in adults. KESIMPTA is a CD20-directed cytolytic anti.
FDA label, Indications and Usage
What it is
Ofatumumab is a recombinant human monoclonal immunoglobulin G1 (IgG1) antibody that binds to human CD20 expressed on B-cells. Ofatumumab is produced in a murine NS0 cell line and consists of two IgG1 heavy chains and two kappa light chains with a molecular weight of approximately 146 kDa.
FDA label, Description section
Boxed warning
None in the current label
How to read this page. FAERS is a spontaneous-reporting system: counts are not incidence rates and a signal is not proof of causation.
Each reaction below is run through an automated screen — is the term in the FDA label (known), in the indications (the disease being treated), an administrative/coding term, or none of these (unlabeled)?
That screen is mechanical text matching, not a causality assessment. The 30 hand-written Bradford Hill assessments are on the causality assessment page. Not medical advice.
Causality screen of the 40 strongest signals
Labeled adverse reaction 3Labeled (related wording) 1Likely indication confounding 7Reporting / coding artifact 4Lab value / disease marker 8Not in label — unassessed 17
What the badges mean
- Labeled adverse reaction The exact term appears in the label's warnings or adverse-reactions sections: a known, expected effect. The FAERS signal confirms the label rather than discovering anything.
- Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
- Likely indication confounding The term appears in the label's indications: reports probably describe the disease being treated (or its progression), not a drug effect. Classic confounding by indication.
- Reporting / coding artifact An administrative, monitoring or exposure term (product issue, off-label use, 'test normal', overdose...). Not a biological reaction; a high PRR here reflects how reports are coded.
- Lab value / disease marker A laboratory result, investigation or disease-activity marker (antibody positive, CRP abnormal, swollen joint count) not described in the label. These usually mirror the monitored disease or testing protocol rather than a drug effect; not screened further.
- Not in label — unassessed Not found in the label text, not an artifact pattern. This is a genuine candidate for a formal causality assessment (Bradford Hill / WHO-UMC); it has NOT had one here.
Strongest disproportionality signals
Flagged terms (PRR ≥ 2, χ² ≥ 4, n ≥ 10), ranked by PRR; infinite PRRs (no comparator reports) excluded. The EBGM column is a second, shrinkage-based estimate (MGPS) with its 5th percentile EB05 and the BCPNN IC025; a pair flagged by PRR alone is marked PRR-only and should be read as fragile. The strata column recomputes the PRR on serious reports only (and, for the 300 most-reported drugs, adjusted for age band), and flags pairs whose reports are unusually skewed by sex or come mostly from consumers. Each row also shows the PRR against the other drugs of the same FDA class, which removes most confounding by the condition being treated, and a calibrated p-value: on validation, known non-causes average an ROR of about 2, so significance is judged against that empirical null (✓ = p < 0.05 after calibration). 1,028 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
Show:
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Multiple sclerosis pseudo relapse | 68 | 164.8 126.2–215.3ROR 165.2 · calibrated p 4e-9 ✓ | 126.1 EB05 102.9 · IC025 +5.7 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 70.8 (51.4–97.5) | Likely indication confounding shares a disease stem with the indications wording | serious n=67 · 81% consumer | not reported in cached trials |
| Autologous haematopoietic stem cell transplant | 14 | 119.9 67.7–212.4ROR 120.0 · calibrated p 2e-7 ✓ | 88.9 EB05 56.3 · IC025 +3.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=14 | not reported in cached trials |
| Cd19 lymphocytes decreased | 20 | 115.8 71.9–186.6ROR 115.9 · calibrated p 2e-7 ✓ | 89.7 EB05 61.3 · IC025 +4.1 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 27.5 (16.6–45.5) | Lab value / disease marker | serious n=14 | not reported in cached trials |
| Expanded disability status scale | 10 | 94.7 48.7–184.2ROR 94.8 · calibrated p 2e-6 ✓ | 71.6 EB05 41.6 · IC025 +3.0 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | – | not reported in cached trials |
| Neuropathic muscular atrophy | 12 | 88.3 48.2–161.6ROR 88.3 · calibrated p 2e-6 ✓ | 69.3 EB05 42.2 · IC025 +3.3 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=12 | not reported in cached trials |
| Expanded disability status scale score increased | 112 | 62.7 51.6–76.1ROR 62.9 · calibrated p 4e-6 ✓ | 56.6 EB05 48.3 · IC025 +5.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 102.8 (78.2–135.1) | Lab value / disease marker | serious n=112 | not reported in cached trials |
| Relapsing multiple sclerosis | 24 | 54.0 35.6–81.9ROR 54.0 · calibrated p 2e-5 ✓ | 48.0 EB05 33.9 · IC025 +4.0 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 18.0 (11.6–27.9) | Likely indication confounding term in indications | serious n=24 · 75% consumer | not reported in cached trials |
| Blood immunoglobulin m decreased | 74 | 50.8 40.1–64.4ROR 50.9 · calibrated p 2e-5 ✓ | 46.5 EB05 38.3 · IC025 +4.8 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 17.8 (13.9–22.9) | Labeled adverse reaction exact term | serious n=33 | NCT02792231: 30/481 (6.2%) on Ofatumumab |
| Band sensation | 91 | 48.6 39.3–60.2ROR 48.8 · calibrated p 2e-5 ✓ | 44.8 EB05 37.6 · IC025 +4.8 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 121.4 (88.3–166.9) | Not in label — unassessed | serious n=53 · 96% consumer | not reported in cached trials |
| B-lymphocyte count decreased | 95 | 48.1 39.1–59.2ROR 48.2 · calibrated p 2e-5 ✓ | 44.4 EB05 37.4 · IC025 +4.8 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 9.0 (7.3–11.1) | Lab value / disease marker | serious n=53 | not reported in cached trials |
| Injection related reaction | 102 | 42.9 35.1–52.4ROR 43.1 · calibrated p 4e-5 ✓ | 40.0 EB05 33.9 · IC025 +4.7 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=44 | NCT02792231: 119/481 (24.7%) on Ofatumumab |
| Hemihypoaesthesia | 19 | 38.2 24.0–60.7ROR 38.2 · calibrated p 2e-4 ✓ | 34.9 EB05 23.6 · IC025 +3.5 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=19 | not reported in cached trials |
| Relapsing-remitting multiple sclerosis | 49 | 38.2 28.6–50.9ROR 38.2 · calibrated p 9e-5 ✓ | 35.6 EB05 28.0 · IC025 +4.3 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 58.9 (41.0–84.7) | Likely indication confounding term in indications | serious n=49 | not reported in cached trials |
| Jc polyomavirus test positive | 48 | 26.9 20.2–36.0ROR 27.0 · calibrated p 6e-4 ✓ | 25.6 EB05 20.1 · IC025 +3.9 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 7.4 (5.5–10.0) | Lab value / disease marker | serious n=28 | not reported in cached trials |
| Aspergillus infection | 261 | 26.6 23.5–30.1ROR 26.8 · calibrated p 5e-4 ✓ | 25.5 EB05 23.0 · IC025 +4.4 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 20.7 (18.2–23.6) | Not in label — unassessed | serious n=261 | not reported in cached trials |
| B-cell aplasia | 10 | 25.9 13.8–48.8ROR 26.0 · calibrated p 0.002 ✓ | 23.7 EB05 13.4 · IC025 +2.5 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=10 | not reported in cached trials |
| Blood immunoglobulin g decreased | 94 | 25.4 20.7–31.3ROR 25.5 · calibrated p 7e-4 ✓ | 24.4 EB05 20.5 · IC025 +4.1 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 13.5 (10.9–16.8) | Lab value / disease marker | serious n=53 | NCT02792231: 30/481 (6.2%) on Ofatumumab |
| Blood immunoglobulin a decreased | 25 | 25.3 17.0–37.7ROR 25.3 · calibrated p 1e-3 ✓ | 24.0 EB05 17.0 · IC025 +3.4 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 11.7 (7.7–17.8) | Lab value / disease marker | serious n=16 | NCT02792231: 30/481 (6.2%) on Ofatumumab |
| Product temperature excursion issue | 179 | 24.8 21.4–28.8ROR 25.0 · calibrated p 7e-4 ✓ | 23.9 EB05 21.1 · IC025 +4.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 363.8 (260.3–508.4) | Reporting / coding artifact | serious n=40 · 81% consumer | not reported in cached trials |
| Influenza like illness (flu-like illness) | 2,900 | 23.1 22.3–23.9ROR 25.2 · calibrated p 6e-4 ✓ | 22.3 EB05 21.6 · IC025 +4.4 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 168.4 (159.3–177.9) | Not in label — unassessed | serious PRR 20.7 · 89% consumer | not reported in cached trials |
| Immunoglobulins decreased | 44 | 21.1 15.6–28.5ROR 21.1 · calibrated p 0.002 ✓ | 20.3 EB05 15.7 · IC025 +3.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 11.9 (8.7–16.3) | Lab value / disease marker | serious n=25 | not reported in cached trials |
| Multiple sclerosis | 1,474 | 20.1 19.1–21.1ROR 20.9 · calibrated p 0.002 ✓ | 19.5 EB05 18.6 · IC025 +4.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 35.3 (33.4–37.2) | Likely indication confounding term in indications | serious PRR 37.3 · 82% consumer | NCT02792231: 1/474 (0.2%) on Ofatumumab (serious AE) |
| Electric shock sensation | 82 | 19.9 16.0–24.8ROR 20.0 · calibrated p 0.002 ✓ | 19.3 EB05 16.0 · IC025 +3.8 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 107.7 (77.9–148.9) | Not in label — unassessed | serious n=53 · 91% consumer | not reported in cached trials |
| Chills | 3,483 | 19.4 18.8–20.0ROR 21.5 · calibrated p 0.001 ✓ | 18.8 EB05 18.3 · IC025 +4.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 89.6 (86.4–93.0) | Labeled adverse reaction exact term | serious PRR 10.5 · 92% consumer | not reported in cached trials |
| Magnetic resonance imaging abnormal | 34 | 18.8 13.4–26.5ROR 18.9 · calibrated p 0.003 ✓ | 18.1 EB05 13.5 · IC025 +3.3 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 12.6 (8.8–18.1) | Reporting / coding artifact | serious n=26 · 74% consumer | not reported in cached trials |
| Temperature intolerance | 277 | 17.7 15.7–19.9ROR 17.8 · calibrated p 0.003 ✓ | 17.2 EB05 15.6 · IC025 +3.9 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 67.7 (58.0–79.1) | Not in label — unassessed | serious n=149 · 93% consumer | not reported in cached trials |
| Multiple sclerosis relapse | 1,705 | 16.0 15.3–16.8ROR 16.8 · calibrated p 0.004 ✓ | 15.7 EB05 15.0 · IC025 +3.9 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 45.7 (43.4–48.0) | Likely indication confounding shares a disease stem with the indications wording | serious PRR 27.9 · 79% consumer | NCT02792231: 1/474 (0.2%) on Ofatumumab (serious AE) |
| Progressive multiple sclerosis | 28 | 15.5 10.7–22.6ROR 15.5 · calibrated p 0.008 ✓ | 14.8 EB05 10.5 · IC025 +3.0 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 33.2 (21.5–51.3) | Likely indication confounding term in indications | serious n=28 · 100% consumer | not reported in cached trials |
| Heat exhaustion | 18 | 15.2 9.5–24.2ROR 15.2 · calibrated p 0.010 ✓ | 14.2 EB05 9.0 · IC025 +2.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=9 | not reported in cached trials |
| Drug effect less than expected | 321 | 14.8 13.2–16.5ROR 14.9 · calibrated p 0.007 ✓ | 14.4 EB05 13.1 · IC025 +3.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 285.4 (227.7–357.8) | Reporting / coding artifact | serious n=86 · 98% consumer | not reported in cached trials |
| Optic neuritis | 207 | 14.7 12.8–16.9ROR 14.8 · calibrated p 0.008 ✓ | 14.4 EB05 12.8 · IC025 +3.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 39.3 (33.5–46.3) | Not in label — unassessed | serious PRR 21.6 · 75% consumer | not reported in cached trials |
| Product supply issue | 159 | 14.6 12.5–17.1ROR 14.7 · calibrated p 0.008 ✓ | 14.3 EB05 12.5 · IC025 +3.5 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Reporting / coding artifact | serious n=69 · 92% consumer | not reported in cached trials |
| Secondary progressive multiple sclerosis | 42 | 14.4 10.6–19.5ROR 14.4 · calibrated p 0.010 ✓ | 13.8 EB05 10.5 · IC025 +3.1 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 43.2 (29.8–62.5) | Likely indication confounding term in indications | serious n=42 · 71% consumer | not reported in cached trials |
| Cytopenia | 264 | 14.3 12.7–16.2ROR 14.4 · calibrated p 0.008 ✓ | 14.0 EB05 12.6 · IC025 +3.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 15.3 (13.4–17.3) | Labeled adverse reaction exact term | serious PRR 18.9 | not reported in cached trials |
| Campylobacter infection | 18 | 14.0 8.8–22.3ROR 14.0 · calibrated p 0.013 ✓ | 12.9 EB05 8.1 · IC025 +2.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=17 | NCT02792218: 1/462 (0.2%) on Ofatumumab (serious AE) |
| Delivery | 14 | 13.7 8.1–23.2ROR 13.7 · calibrated p 0.016 ✓ | 12.2 EB05 7.0 · IC025 +2.3 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=9 | not reported in cached trials |
| Brain fog | 304 | 13.5 12.0–15.1ROR 13.6 · calibrated p 0.011 ✓ | 13.2 EB05 12.0 · IC025 +3.5 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 70.1 (60.4–81.4) | Labeled (related wording) related wording | serious PRR 20.1 · 93% consumer | not reported in cached trials |
| T-lymphocyte count decreased | 13 | 12.3 7.1–21.3ROR 12.3 · calibrated p 0.024 ✓ | 10.6 EB05 5.9 · IC025 +2.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 20.5 (11.2–37.6) | Lab value / disease marker | serious n=9 | not reported in cached trials |
| Feeling of body temperature change | 107 | 11.8 9.7–14.2ROR 11.8 · calibrated p 0.019 ✓ | 11.4 EB05 9.7 · IC025 +3.1 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 338.2 (222.0–515.3) | Not in label — unassessed | serious n=56 · 94% consumer | not reported in cached trials |
| Ophthalmic migraine | 12 | 11.6 6.5–20.5ROR 11.6 · calibrated p 0.030 ✓ | 9.7 EB05 5.3 · IC025 +2.0 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | – | not reported in cached trials |
Trial evidence (ClinicalTrials.gov)
✓ Trial adverse-event data found on ClinicalTrials.gov
Largest completed trials with posted results that list Ofatumumab as a study intervention. The right-hand column of the signal table shows whether each FAERS term was also recorded in these trials, with a real denominator (7 of 40 signal terms matched).
- NCT02792231 — Efficacy and Safety of Ofatumumab Compared to Teriflunomide in Patients With Relapsing Multiple Sclerosis. (N=955, PHASE3; 201 AE terms posted; arms: OMB 20mg; TER 14mg)
- NCT02792218 — Efficacy and Safety of Ofatumumab Compared to Teriflunomide in Patients With Relapsing Multiple Sclerosis (N=930, PHASE3; 115 AE terms posted; arms: OMB 20mg; TER 14mg)
Caveats: trial populations, doses and follow-up differ from the reporting population; AE terms are sponsor-coded and matched here by wording; absence from a trial list means the term was not reported above the sponsor's frequency threshold, not that it cannot occur.
Most frequently reported reactions
By raw co-report count, regardless of disproportionality. Common terms here are often the illness itself or generic outcomes.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Fatigue (tiredness) | 5,534 | 4.5 4.4–4.7ROR 5.3 · calibrated p 0.208 | 4.5 EB05 4.4 · IC025 +2.1 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 19.8 (19.8–19.8) | Labeled adverse reaction exact term | serious PRR 4.3 · 91% consumer | NCT02792231: 25/481 (5.2%) on Ofatumumab |
| Headache | 4,633 | 4.7 4.6–4.9ROR 5.3 · calibrated p 0.201 | 4.7 EB05 4.6 · IC025 +2.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 29.2 (28.8–29.7) | Labeled adverse reaction exact term | serious PRR 4.4 · 91% consumer | NCT02792231: 1/481 (0.2%) on Ofatumumab (serious AE) |
| Pyrexia (fever) | 3,578 | 6.6 6.4–6.8ROR 7.3 · calibrated p 0.087 | 6.6 EB05 6.4 · IC025 +2.7 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 22.2 (21.8–22.7) | Labeled (related wording) related wording | serious PRR 4.3 · 83% consumer | NCT02792231: 1/481 (0.2%) on Ofatumumab (serious AE) |
| Pain | 3,564 | 3.7 3.6–3.8ROR 4.0 · calibrated p 0.374 | 3.7 EB05 3.6 · IC025 +1.8 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 14.8 (14.5–15.1) | Labeled adverse reaction exact term | serious PRR 2.7 · 92% consumer | NCT02792231: 1/481 (0.2%) on Ofatumumab (serious AE) |
| Chills | 3,483 | 19.4 18.8–20.0ROR 21.5 · calibrated p 0.001 ✓ | 18.8 EB05 18.3 · IC025 +4.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 89.6 (86.4–93.0) | Labeled adverse reaction exact term | serious PRR 10.5 · 92% consumer | not reported in cached trials |
| Influenza like illness (flu-like illness) | 2,900 | 23.1 22.3–23.9ROR 25.2 · calibrated p 6e-4 ✓ | 22.3 EB05 21.6 · IC025 +4.4 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 168.4 (159.3–177.9) | Not in label — unassessed | serious PRR 20.7 · 89% consumer | not reported in cached trials |
| Nausea | 1,815 | 1.5 1.4–1.5ROR 1.5 · calibrated p 0.634 | 1.5 EB05 1.4 · IC025 +0.5 vs other CD20-directed Cytolytic Antibodys: PRR 11.5 (11.1–12.0) | Labeled adverse reaction exact term | serious PRR 1.5 · 85% consumer | NCT02792231: 30/481 (6.2%) on Ofatumumab |
| Multiple sclerosis relapse | 1,705 | 16.0 15.3–16.8ROR 16.8 · calibrated p 0.004 ✓ | 15.7 EB05 15.0 · IC025 +3.9 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 45.7 (43.4–48.0) | Likely indication confounding shares a disease stem with the indications wording | serious PRR 27.9 · 79% consumer | NCT02792231: 1/474 (0.2%) on Ofatumumab (serious AE) |
| Covid-19 | 1,519 | 5.5 5.2–5.8ROR 5.7 · calibrated p 0.171 | 5.4 EB05 5.2 · IC025 +2.4 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 6.8 (6.5–7.1) | Not in label — unassessed | serious PRR 5.5 · 83% consumer | not reported in cached trials |
| Asthenia (weakness) | 1,506 | 2.5 2.4–2.7ROR 2.6 · calibrated p 0.763 | 2.5 EB05 2.4 · IC025 +1.3 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 13.7 (13.1–14.4) | Not in label — unassessed | serious PRR 2.3 · 87% consumer | not reported in cached trials |
| Multiple sclerosis | 1,474 | 20.1 19.1–21.1ROR 20.9 · calibrated p 0.002 ✓ | 19.5 EB05 18.6 · IC025 +4.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 35.3 (33.4–37.2) | Likely indication confounding term in indications | serious PRR 37.3 · 82% consumer | NCT02792231: 1/474 (0.2%) on Ofatumumab (serious AE) |
| Gait disturbance | 1,428 | 4.8 4.5–5.0ROR 4.9 · calibrated p 0.243 | 4.7 EB05 4.5 · IC025 +2.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 19.8 (18.8–20.8) | Not in label — unassessed | serious PRR 5.3 · 88% consumer | not reported in cached trials |
| Hypoaesthesia (numbness) | 1,401 | 6.0 5.7–6.3ROR 6.2 · calibrated p 0.138 | 5.9 EB05 5.7 · IC025 +2.5 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 19.3 (18.4–20.3) | Not in label — unassessed | serious PRR 6.7 · 88% consumer | NCT02792218: 1/462 (0.2%) on Ofatumumab (serious AE) |
| Malaise (feeling unwell) | 1,368 | 2.0 1.9–2.1ROR 2.0 · calibrated p 0.955 | 2.0 EB05 1.9 · IC025 +0.9 vs other CD20-directed Cytolytic Antibodys: PRR 12.1 (11.5–12.7) | Not in label — unassessed | serious PRR 2.3 · 85% consumer | not reported in cached trials |
| Feeling abnormal | 1,357 | 3.6 3.4–3.8ROR 3.7 · calibrated p 0.437 | 3.6 EB05 3.4 · IC025 +1.7 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 55.4 (52.1–58.9) | Not in label — unassessed | serious PRR 4.6 · 93% consumer | not reported in cached trials |
Unlabeled candidate signals
These flagged terms were not found in the FDA label text and do not match an artifact pattern. They are the pairs that would merit a structured assessment (temporality, dose-response, biological plausibility, consistency across databases, trial or cohort evidence). The screen has not done that; string-matching misses label wording, and a strong PRR can still be stimulated reporting, co-medication, or the disease itself.
- Band sensation — n=91, PRR 48.6
- Injection related reaction — n=102, PRR 42.9 (also seen in trial arm)
- Aspergillus infection — n=261, PRR 26.6
- Influenza like illness — n=2,900, PRR 23.1
- Electric shock sensation — n=82, PRR 19.9
- Temperature intolerance — n=277, PRR 17.7
- Optic neuritis — n=207, PRR 14.7
- Feeling of body temperature change — n=107, PRR 11.8
Want to assess one of these properly? The runbook describes the Bradford Hill / trial-evidence workflow used on the assessment page, and handoff_top1000_signals.csv lists the strongest unassessed pairs across all drugs.
Common questions
What are the most reported side effects of Ofatumumab?
In FDA FAERS, the most frequently co-reported reaction terms for Ofatumumab are fatigue, headache, pyrexia, pain, chills, influenza like illness. These are report counts, not rates: FAERS has no denominator, reporting is voluntary and uneven, and a term can be reported because of the illness being treated rather than the drug.
Does Ofatumumab have an FDA boxed warning?
No. The FDA label retrieved for Ofatumumab has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Ofatumumab causes these side effects?
No. A disproportionality signal (PRR, ROR) means a reaction is reported more often with this drug than with others in the database. That can reflect a real effect, but also the disease being treated, stimulated reporting after news or litigation, co-medications, or how reports are coded. Causality needs temporality, dose-response, biological plausibility, consistency across data sources and, ideally, trial or cohort evidence. This page screens each term against the FDA label and ClinicalTrials.gov results; it does not establish causation.
Sources & methods
- FDA label via openFDA (set ID 6a8a3f53-2062-48ff-9dbe-b939df133ca3, effective 20260401; matched on
openfda.generic_name.exact:"OFATUMUMAB") - Bayesian shrinkage measures computed offline over all 1,317,300 cached pairs: BCPNN information component (IC, with Norén closed-form IC025) and MGPS empirical-Bayes geometric mean (EBGM, EB05) with a two-component gamma prior fitted by maximum marginal likelihood (α₁=0.57, β₁=0.02, α₂=1.42, β₂=0.70, w=0.17); unstratified
- FAERS pair statistics from the OpenPV build of 2026-09-14 (openFDA
count=aggregation, fieldpatient.drug.openfda.generic_name.exact, 1,068 reaction terms, min 3 co-reports); PRR/ROR with 95% CI, chi-square with Yates correction - Serious-only and stratified counts (serious:1, patient.patientsex, primarysource.qualification) from openFDA count queries; serious-only PRR uses the drug serious report total and the term global serious total (N_serious=11,882,979); strata shown only when n ≥ 20
- Seriousness and sex counts from openFDA
count=serious,patient.patientsex,seriousnessdeath - ClinicalTrials.gov API v2 (query
OFATUMUMAB, results-bearing studies sorted by enrollment)
Page generated 2026-10-14. Label and PubChem text are retrieved automatically and may lag the current label; always check the current prescribing information. OpenPV is a beta research tool of the Open Source Medicine Foundation.