Dupilumab

What it is

Dupilumab is a laboratory-made antibody – a fully human IgG4 monoclonal antibody – given as an injection under the skin. It is not a steroid and not a small-molecule drug; it is a protein that is broken down into amino acids like any other antibody, which is why it does not interact with the liver enzymes most drugs use. Its single target is the alpha subunit of the interleukin-4 receptor, a docking point shared by two inflammatory signals, IL-4 and IL-13. Because those two signals sit at the centre of “type 2” inflammation, one drug has turned out to work across a cluster of apparently unrelated diseases, from eczema to nasal polyps to a form of COPD.

What the research says

Dupilumab has unusually consistent placebo-controlled evidence across several conditions, each with its own pivotal trial. In moderate-to-severe eczema, 38% of patients reached clear or almost-clear skin at 16 weeks versus 10% on placebo. In uncontrolled asthma it cut severe exacerbations by about 48% (0.46 versus 0.87 per year). In severe nasal polyps it shrank polyp size. In eosinophilic oesophagitis, 60% achieved histological remission versus 5% on placebo. In prurigo nodularis, 60% achieved a meaningful drop in itch versus 18%. In COPD with high eosinophils it reduced exacerbations by 30%. The characteristic harm is eye inflammation: a meta-analysis of 23 trials found conjunctivitis nearly twice as common overall, and two and a half times as common in eczema patients specifically – though notably not raised at all in the non-eczema indications. A paradoxical red face and neck is a separate, well-described reaction. There is no boxed warning.

Evidence grade: Well established.

How it works

Drug class: Interleukin-4 receptor alpha (IL-4Rα) antagonist; fully human IgG4 monoclonal antibody (biologic)

Two inflammatory messengers, interleukin-4 and interleukin-13, both have to dock onto a shared receptor component called IL-4Rα to deliver their signal. Dupilumab binds that component and blocks it, so neither messenger can get its message through. Downstream, that quiets the cells and mediators of type 2 inflammation – mast cells, basophils, eosinophils, goblet cells, IgE – which is why the same injection helps eczema, asthma, nasal polyps and eosinophilic oesophagitis. The label is careful to say the mechanism has not been definitively established. (Source 1)

What it is used for

• In two identical 16-week phase 3 trials (SOLO 1 and SOLO 2, 1,379 patients), 38% of patients on dupilumab every other week reached clear or almost-clear skin versus 10% on placebo in SOLO 1, and 36% versus 8% in SOLO 2 – an absolute gain of about 28 percentage points in each trial. Evidence: established. (Source 2)
• In LIBERTY ASTHMA QUEST (1,902 patients, 52 weeks) dupilumab cut the annual rate of severe exacerbations from 0.87 to 0.46, a 47.7% reduction, with greater benefit in people with higher blood eosinophil counts. Evidence: established. (Source 3)
• Two phase 3 trials (SINUS-24 and SINUS-52, 724 patients) found dupilumab reduced nasal polyp score by 2.06 points more than placebo at 24 weeks in SINUS-24 and by 1.80 points in SINUS-52, with improvement in congestion and CT opacification in both. Evidence: established. (Source 4)
• In the phase 3 LIBERTY EoE TREET trial, weekly dupilumab produced histological remission in 60% versus 5% on placebo at 24 weeks – a 55 percentage point absolute difference – alongside improvement in swallowing symptoms. Evidence: established. (Source 5)
• Two phase 3 trials (LIBERTY-PN PRIME and PRIME2, 311 patients) met their primary endpoints: a 4-point or greater drop in worst-itch score was achieved by 60.0% versus 18.4% at week 24 in PRIME, and 37.2% versus 22.0% at week 12 in PRIME2. Evidence: established. (Source 6)
• In BOREAS (939 patients with blood eosinophils ≥300/µL already on triple inhaled therapy), dupilumab reduced moderate or severe exacerbations from 1.10 to 0.78 per year (rate ratio 0.70, P<0.001) and improved prebronchodilator FEV1 by 83 mL more than placebo at week 12. Evidence: established. (Source 7)
• The April 2026 US label records approval for all three. We did not retrieve the pivotal trial reports for these indications in this research pass, so the strength of the underlying evidence is not assessed here – the approval is recorded as a regulatory position, not as evidence. Evidence: unknown. (Source 8)

Interactions

• Live vaccines (label): Live vaccines are avoided during treatment, not because harm has been shown but because nobody has tested whether they still work or remain safe. The label advises catching up on age-appropriate vaccinations before starting. (Source 9)
• Drugs cleared by liver CYP enzymes – warfarin, omeprazole, metoprolol, midazolam (pharmacokinetic study): A dedicated study at twice the approved dosing frequency found no clinically meaningful change in how the body handled any of these, with a 29% rise in metoprolol exposure as the largest signal. This is the opposite of what happens with small-molecule drugs. (Source 10)
• Caffeine (coffee, tea, cola) (pharmacokinetic study): Caffeine was used as the probe for the CYP1A2 pathway in that same study, and its exposure was not clinically changed – so there is no documented reason to alter caffeine intake on dupilumab. (Source 10)
• Anti-helminth (anti-worm) treatment and pre-existing parasite infection (label): Because IL-4 and IL-13 are part of the immune response to parasites, a pre-existing worm infection should be treated before dupilumab is started, and dupilumab is held if an infection does not respond. (Source 9)
• Non-live vaccines (tetanus toxoid, meningococcal polysaccharide) (clinical trial): Antibody responses to tetanus and serogroup C meningococcal polysaccharide were similar in dupilumab-treated and placebo-treated adults, so these vaccines appear to still work. Responses to other non-live vaccines were not tested. (Source 9)

Stopping it

• The only randomised trial of dupilumab withdrawal, SOLO-CONTINUE, took 422 people who had responded well at 16 weeks and re-randomised them. Continuing weekly or fortnightly injections held the response; stretching to every 4 or 8 weeks, or going to placebo, let it slip away on every measure. There is no withdrawal syndrome in the dependence sense – the issue is that the disease comes back. (Source 11)
• That trial's conclusion is why the approved long-term regimen stayed at every 2 weeks rather than being spaced out once people improve. (Source 11)
• The label describes eye disease as a reason some people stop: postmarketing reports include conjunctivitis, keratitis and blepharitis severe enough to lead to discontinuation or surgery, and it advises considering stopping dupilumab if keratitis develops or conjunctivitis does not resolve with standard treatment. (Source 12)
• Dupilumab leaves the body slowly, so stopping is not immediate: after the last steady-state dose the median time to an undetectable blood level is 9 to 13 weeks in adults and adolescents, and up to 32 weeks in the youngest children. (Source 13)

What goes wrong

In the two eczema trials, injection-site reactions and conjunctivitis were more common on dupilumab than on placebo. (Source 2)

• Randomized trial, High certainty.
• Size: 1,379 patients across SOLO 1 and SOLO 2.
• Who: Adults with moderate-to-severe atopic dermatitis.
• How long: 16 weeks.
• Result: Reported as more frequent in the dupilumab groups than the placebo groups; the abstract does not give the rates.
• Funding: industry-funded (Sanofi and Regeneron)

Injection-site reactions and conjunctivitis were more frequent in the dupilumab groups than in the placebo groups.

Blood eosinophilia appeared after starting treatment in about 4% of people given dupilumab in the asthma trial, against under 1% on placebo. (Source 3)

• Randomized trial, High certainty.
• Size: 1,902 patients aged 12 and over.
• Who: People 12 or older with uncontrolled moderate-to-severe asthma.
• How long: 52 weeks.
• Result: Blood eosinophilia in 52 of the dupilumab recipients (4.1%) versus 4 placebo recipients (0.6%)
• Funding: industry-funded (Sanofi and Regeneron)

Blood eosinophilia occurred after the start of the intervention in 52 patients (4.1%) who received dupilumab as compared with 4 patients (0.6%) who received placebo.

Across 23 placebo-controlled trials, dupilumab nearly doubled the risk of conjunctivitis. (Source 14)

• Meta-analysis, Moderate certainty.
• Size: 23 randomised controlled trials, 9,153 patients.
• Who: Patients with atopic dermatitis, asthma, chronic rhinosinusitis with nasal polyps or eosinophilic oesophagitis in placebo-controlled trials.
• How long: trial durations as published.
• Result: Overall risk ratio 1.89 (95% CI 1.34–2.67); in atopic dermatitis specifically RR 2.43 (95% CI 1.84–3.12)
• Funding: not stated.

Dupilumab users exhibited significantly higher risk of conjunctivitis (risk ratio [RR], 1.89; 95% confidence interval [CI], 1.34-2.67) than placebo users.

In the eczema registration trials conjunctivitis occurred in 10% on dupilumab versus 2% on placebo, and injection-site reactions in 10% versus 5%. (Source 15)

• Official position, Certainty not rated.
• Size: 529 on dupilumab 300 mg every 2 weeks and 517 on placebo (pooled monotherapy trials); 110 and 315 in the trial with background topical steroids.
• Who: Adults with moderate-to-severe atopic dermatitis in SOLO 1, SOLO 2, AD-1021 and CHRONOS.
• How long: 16 weeks.
• Result: Conjunctivitis cluster 51 (10%) versus 12 (2%) in monotherapy and 10 (9%) versus 15 (5%) with background topical steroids; injection-site reaction 51 (10%) versus 28 (5%); blepharitis 2 (<1%) versus 1 (<1%) monotherapy but 5 (5%) versus 2 (1%) with topical steroids; keratitis 1 (<1%) versus 0.
• Funding: industry-funded (manufacturer's label)

Injection site reaction 51 (10) 28 (5) 11 (10) 18 (6) Conjunctivitis § 51 (10) 12 (2) 10 (9) 15 (5)

Dupilumab's eye problems are not limited to eczema trials: postmarketing reports include keratitis and blepharitis, and in some cases transient or ongoing visual impairment including blindness. (Source 12)

• Case series, Very low certainty.
• Size: Spontaneous postmarketing reports; numbers not given.
• Who: Predominantly patients with atopic dermatitis in routine use.
• How long: not stated.
• Result: No rates; reports describe varying degrees of transient or ongoing visual impairment including blindness, leading to discontinuation and/or surgical intervention.
• Funding: industry-funded (manufacturer's label)

Some patients reported varying degrees of transient or ongoing visual impairment including blindness associated with conjunctivitis, keratitis, or blepharitis leading to discontinuation of DUPIXENT and/or surgical intervention.

A distinct paradoxical red face and neck can appear on dupilumab even while eczema elsewhere clears, and it does not respond to the usual treatments. (Source 16)

• Case series, Very low certainty.
• Size: 7 patients.
• Who: Adults with atopic dermatitis treated with dupilumab.
• How long: erythema appeared 10–39 weeks after starting dupilumab.
• Result: Sharply demarcated patchy erythema of the head and neck with little scaling; eczema elsewhere had greatly improved in six of seven; treatment of the erythema with topical and systemic drugs was unsuccessful; biopsies showed ectatic capillaries and perivascular lymphohistiocytic infiltration, with spongiosis largely absent.
• Funding: not stated.

We report on seven patients with AD presenting with a paradoxical head and neck erythema that appeared 10-39 weeks after the start of dupilumab treatment.

In the asthma trials, injection-site reactions and eosinophilia were the adverse reactions clearly more common than placebo. (Source 17)

• Official position, Certainty not rated.
• Size: 779 on 200 mg every 2 weeks, 788 on 300 mg every 2 weeks, 792 on placebo.
• Who: Patients with moderate-to-severe asthma in DRI12544 and QUEST.
• How long: 24–52 weeks.
• Result: Injection site reactions 111 (14%) and 144 (18%) versus 50 (6%) on placebo; oropharyngeal pain 2% versus 1%; eosinophilia 2% in both dupilumab arms versus <1% on placebo.
• Funding: industry-funded (manufacturer's label)

Injection site reactions * 111 (14%) 144 (18%) 50 (6%) Oropharyngeal pain 13 (2%) 19 (2%) 7 (1%) Eosinophilia † 17 (2%) 16 (2%) 2 (<1%)

Stretching the dosing interval or stopping dupilumab after a good 16-week response led to loss of that response. (Source 18)

• Randomized trial, Moderate certainty.
• Size: 422 patients re-randomised.
• Who: Adults with moderate-to-severe atopic dermatitis who had achieved IGA 0/1 or EASI-75 at week 16 in SOLO 1 or SOLO 2.
• How long: 36 weeks of re-randomised treatment.
• Result: Percent EASI improvement from SOLO baseline changed by -0.06% on continued weekly or every-2-week dosing (P < .001 vs placebo) against -3.84% every 4 weeks, -6.84% every 8 weeks and -21.67% on placebo. EASI-75 response was maintained by 116 of 162 (71.6%) on weekly or every-2-week dosing versus 49 of 84 (58.3%) every 4 weeks, 45 of 82 (54.9%) every 8 weeks and 24 of 79 (30.4%) on placebo.
• Funding: industry-funded (Sanofi and Regeneron)

continuing dupilumab treatment once weekly or every 2 weeks maintained optimal efficacy, with negligible change in percent EASI improvement from SOLO 1 and 2 baseline during the SOLO-CONTINUE trial (-0.06%; P < .001 vs placebo); percent change with the other regimens dose-dependently worsened (dupilumab every 4 weeks, -3.84%; dupilumab every 8 weeks, -6.84%; placebo, -21.67%).

Helminth (worm) infections were more common in children treated with dupilumab for asthma, and pre-existing worm infections need treating first. (Source 9)

• Official position, Certainty not rated.
• Size: Pediatric asthma development programme (6 cases reported)
• Who: Children aged 6 to 11 with asthma.
• How long: trial duration.
• Result: 5 cases of enterobiasis and 1 case of ascariasis reported as adverse reactions in the paediatric asthma programme.
• Funding: industry-funded (manufacturer's label)

Adverse reactions of helminth infections (5 cases of enterobiasis and 1 case of ascariasis) were reported in pediatric subjects 6 to 11 years old who participated in the pediatric asthma development program

What the evidence supports

In moderate-to-severe eczema, dupilumab got roughly three to four times as many people to clear or almost-clear skin as placebo, in two trials of identical design. (Source 2)

• Randomized trial, High certainty.
• Size: 671 patients in SOLO 1 and 708 in SOLO 2 (1,379 total)
• Who: Adults with moderate-to-severe atopic dermatitis inadequately controlled by topical treatment.
• How long: 16 weeks.
• Result: Primary outcome (IGA 0 or 1 plus a ≥2-point reduction) in SOLO 1: 85 patients (38%) on dupilumab every other week and 83 (37%) weekly versus 23 (10%) on placebo; in SOLO 2: 84 (36%) every other week and 87 (36%) weekly versus 20 (8%) on placebo. P<0.001 for every comparison with placebo. Absolute difference about 28 percentage points in SOLO 1 and 28 points in SOLO 2.
• Funding: industry-funded (Sanofi and Regeneron)

In SOLO 1, the primary outcome occurred in 85 patients (38%) who received dupilumab every other week and in 83 (37%) who received dupilumab weekly, as compared with 23 (10%) who received placebo (P<0.001 for both comparisons with placebo). The results were similar in SOLO 2, with the primary outcome occurring in 84 patients (36%) who received dupilumab every other week and in 87 (36%) who received dupilumab weekly, as compared with 20 (8%) who received placebo (P<0.001 for both comparisons).

In uncontrolled moderate-to-severe asthma, dupilumab roughly halved the rate of severe exacerbations over a year. (Source 3)

• Randomized trial, High certainty.
• Size: 1,902 patients aged 12 and over.
• Who: People 12 years or older with uncontrolled moderate-to-severe asthma on existing controller therapy.
• How long: 52 weeks.
• Result: Annualised severe exacerbation rate 0.46 (95% CI 0.39-0.53) on dupilumab 200 mg every 2 weeks versus 0.87 (95% CI 0.72-1.05) on matched placebo – 47.7% lower, P<0.001, an absolute difference of about 0.41 exacerbations per patient-year. At week 12 pre-bronchodilator FEV1 rose 0.32 L on the lower dose, a difference of 0.14 L versus placebo (P<0.001)
• Funding: industry-funded (Sanofi and Regeneron)

The annualized rate of severe asthma exacerbations was 0.46 (95% confidence interval [CI], 0.39 to 0.53) among patients assigned to 200 mg of dupilumab every 2 weeks and 0.87 (95% CI, 0.72 to 1.05) among those assigned to a matched placebo, for a 47.7% lower rate with dupilumab than with placebo (P<0.001); similar results were seen with the dupilumab dose of 300 mg every 2 weeks. At week 12, the FEV1 had increased by 0.32 liters in patients assigned to the lower dose of dupilumab (difference vs. matched placebo, 0.14 liters; P<0.001)

The asthma benefit was larger in people who started with higher blood eosinophil counts. (Source 3)

• Randomized trial, High certainty.
• Size: 1,902 patients.
• Who: People 12 and over with uncontrolled asthma and a blood eosinophil count of 300 or more per cubic millimetre.
• How long: 52 weeks.
• Result: Annualised severe exacerbation rate 0.37 (95% CI 0.29-0.48) on lower-dose dupilumab versus 1.08 (95% CI 0.85-1.38) on matched placebo in this subgroup – 65.8% lower (95% CI 52.0 to 75.6), against 47.7% lower in the whole trial population.
• Funding: industry-funded (Sanofi and Regeneron)

Among patients with a blood eosinophil count of 300 or more per cubic millimeter, the annualized rate of severe asthma exacerbations was 0.37 (95% CI, 0.29 to 0.48) among those receiving lower-dose dupilumab and 1.08 (95% CI, 0.85 to 1.38) among those receiving a matched placebo (65.8% lower rate with dupilumab than with placebo; 95% CI, 52.0 to 75.6)

In severe chronic rhinosinusitis with nasal polyps, dupilumab shrank polyps by about two points on the nasal polyp score compared with placebo in one trial and about 1.8 points in the other. (Source 4)

• Randomized trial, High certainty.
• Size: 276 patients in SINUS-24 and 448 in SINUS-52 (724 total)
• Who: Adults with severe bilateral nasal polyps despite intranasal steroids, prior systemic steroids or prior sinus surgery; with and without comorbid asthma.
• How long: 24 weeks for the co-primary endpoints; 52 weeks in SINUS-52.
• Result: Least-squares mean difference in nasal polyp score versus placebo at 24 weeks: -2.06 (95% CI -2.43 to -1.69; p<0.0001) in SINUS-24 and -1.80 (-2.10 to -1.51; p<0.0001) in SINUS-52, on a scale where 8 is the maximum. Nasal congestion or obstruction score differed by -0.89 and -0.87 and Lund-Mackay CT score by -7.44 and -5.13 in the two trials, all p<0.0001.
• Funding: industry-funded (Sanofi and Regeneron)

At 24 weeks, least squares mean difference in NPS of dupilumab treatment versus placebo was -2·06 (95% CI -2·43 to -1·69; p<0·0001) in SINUS-24 and -1·80 (-2·10 to -1·51; p<0·0001) in SINUS-52

In eosinophilic oesophagitis, weekly dupilumab produced histological remission in about 60% of patients versus 5-6% on placebo in both parts of the trial. (Source 5)

• Randomized trial, High certainty.
• Size: 81 patients in Part A (42 dupilumab, 39 placebo) and 240 in Part B (80 weekly, 81 every 2 weeks, 79 placebo)
• Who: Patients aged 12 and older with eosinophilic oesophagitis.
• How long: 24 weeks (with extension to 52 weeks)
• Result: Histological remission (≤6 eosinophils per high-power field) in Part A: 25 of 42 (60%) versus 2 of 39 (5%), difference 55 percentage points (95% CI 40 to 71), P<0.001. Part B: 47 of 80 (59%) weekly and 49 of 81 (60%) every 2 weeks versus 5 of 79 (6%) placebo, difference for weekly 54 percentage points (95% CI 41 to 66), P<0.001.
• Funding: industry-funded (Sanofi and Regeneron)

In Part A, histologic remission occurred in 25 of 42 patients (60%) who received weekly dupilumab and in 2 of 39 patients (5%) who received placebo (difference, 55 percentage points; 95% confidence interval [CI], 40 to 71; P<0.001). In Part B, histologic remission occurred in 47 of 80 patients (59%) with weekly dupilumab, in 49 of 81 patients (60%) with dupilumab every 2 weeks, and in 5 of 79 patients (6%) with placebo

In prurigo nodularis, dupilumab achieved a clinically meaningful reduction in itch in 60% of patients versus 18% on placebo, but the second trial's result was much smaller. (Source 6)

• Randomized trial, Moderate certainty.
• Size: 151 patients in PRIME and 160 in PRIME2 (311 total)
• Who: Adults with prurigo nodularis, at least 20 nodules and severe itch uncontrolled by topical therapy.
• How long: 24 weeks (PRIME primary endpoint) and 12 weeks (PRIME2)
• Result: ≥4-point reduction in Worst Itch NRS: 60.0% versus 18.4% at week 24 in PRIME (P < 0.001); 37.2% versus 22.0% at week 12 in PRIME2 (95% CI 2.3–31.2; P = 0.022). The absolute gain was about 42 percentage points in one trial and 15 in the other.
• Funding: industry-funded (Sanofi and Regeneron)

A ≥4-point WI-NRS reduction at week 24 in the dupilumab and placebo arms was achieved by 60.0% and 18.4% of patients, respectively, in PRIME (95% confidence interval (CI), 27.8-57.7 for the difference, P < 0.001) and at week 12 by 37.2% and 22.0% of patients, respectively, in PRIME2 (95% CI, 2.3-31.2; P = 0.022).

In COPD with high blood eosinophils, dupilumab reduced moderate or severe exacerbations by 30% on top of triple inhaled therapy. (Source 7)

• Randomized trial, High certainty.
• Size: 939 patients (468 dupilumab, 471 placebo)
• Who: Patients with COPD, blood eosinophil count at least 300 per microlitre and raised exacerbation risk despite standard triple inhaled therapy.
• How long: 52 weeks, primary endpoint annualised.
• Result: Annualised moderate or severe exacerbations 0.78 (95% CI 0.64-0.93) versus 1.10 (95% CI 0.93-1.30); rate ratio 0.70 (95% CI 0.58-0.86; P<0.001) – an absolute reduction of about 0.32 exacerbations per patient-year. Prebronchodilator FEV1 at week 12 rose 160 mL versus 77 mL, a difference of 83 mL (95% CI 42 to 125; P<0.001), sustained through week 52. St George's Respiratory Questionnaire score differed by -3.4 (95% CI -5.5 to -1.3; P = 0.002) and E-RS-COPD by -1.1 (95% CI -1.8 to -0.4; P = 0.001) at week 52.
• Funding: industry-funded (Sanofi and Regeneron)

The annualized rate of moderate or severe exacerbations was 0.78 (95% confidence interval [CI], 0.64 to 0.93) with dupilumab and 1.10 (95% CI, 0.93 to 1.30) with placebo (rate ratio, 0.70; 95% CI, 0.58 to 0.86; P<0.001). The prebronchodilator FEV1 increased from baseline to week 12 by a least-squares (LS) mean of 160 ml (95% CI, 126 to 195) with dupilumab and 77 ml (95% CI, 42 to 112) with placebo (LS mean difference, 83 ml; 95% CI, 42 to 125; P<0.001), a difference that was sustained through week 52.

What the evidence does not support

In the same trial, the every-2-week regimen changed the tissue measure but did not improve swallowing symptoms. (Source 5)

• Randomized trial, High certainty.
• Size: 240 patients in Part B.
• Who: Patients aged 12 and older with eosinophilic oesophagitis.
• How long: 24 weeks.
• Result: Dysphagia Symptom Questionnaire score improved versus placebo by -12.32 (95% CI -19.11 to -5.54) in Part A and -9.92 (95% CI -14.81 to -5.02) in Part B with weekly dosing (both P<0.001), but by only -0.51 (95% CI -5.42 to 4.41) with dupilumab every 2 weeks in Part B.
• Funding: industry-funded (Sanofi and Regeneron)

the scores improved with weekly dupilumab as compared with placebo, with differences of -12.32 (95% CI, -19.11 to -5.54) in Part A and -9.92 (95% CI, -14.81 to -5.02) in Part B (both P<0.001) but not with dupilumab every 2 weeks (difference in Part B, -0.51; 95% CI, -5.42 to 4.41)

The conjunctivitis risk was confined to eczema: in the non-eczema indications dupilumab did not increase it at all. (Source 14)

• Meta-analysis, Moderate certainty.
• Size: 23 randomised controlled trials, 9,153 patients, subgrouped by indication.
• Who: Patients with asthma, chronic rhinosinusitis with nasal polyps or eosinophilic oesophagitis (the non-atopic-dermatitis subgroup)
• How long: trial durations as published.
• Result: Non-atopic-dermatitis indications RR 0.71 (95% CI 0.43–1.13), not statistically significant, versus RR 2.43 (1.84–3.12) in atopic dermatitis.
• Funding: not stated.

significantly increased incidence of conjunctivitis was observed in the dupilumab group relative to the placebo group among patients with AD (RR, 2.43; 95% CI, 1.84-3.12) but not among patients with non-AD indications (RR, 0.71; 95% CI, 0.43-1.13)

Dupilumab did not meaningfully change the handling of drugs metabolised by the main liver enzymes, including warfarin and caffeine. (Source 10)

• Blood level study, Low certainty.
• Size: 12–13 evaluable subjects.
• Who: Adults with atopic dermatitis given a 600 mg loading dose then 300 mg weekly for six weeks – twice the approved dosing frequency.
• How long: 6 weeks.
• Result: No clinically significant changes in AUC for midazolam (CYP3A4), warfarin (CYP2C9), omeprazole (CYP2C19), metoprolol (CYP2D6) or caffeine (CYP1A2); the largest effect was a 29% AUC increase for metoprolol.
• Funding: industry-funded (manufacturer's label)

No clinically significant changes in AUC were observed. The largest effect was observed for metoprolol (CYP2D6) with an increase in AUC of 29%.

Where the evidence is mixed

The eczema trials' own authors flagged that long-term effectiveness and safety were not yet established. (Source 19)

• Randomized trial, High certainty.
• Size: 1,379 patients.
• Who: Adults with moderate-to-severe atopic dermatitis.
• How long: 16 weeks.
• Result: Benefits reported for signs, symptoms, pruritus, anxiety and depression symptoms and quality of life; duration limited to 16 weeks.
• Funding: industry-funded (Sanofi and Regeneron)

dupilumab improved the signs and symptoms of atopic dermatitis, including pruritus, symptoms of anxiety and depression, and quality of life, as compared with placebo. Trials of longer duration are needed to assess the long-term effectiveness and safety of dupilumab.

Where the research disagrees

Whether dupilumab causes conjunctivitis as a general drug effect or only in people with atopic dermatitis

• Chen and colleagues, meta-analysis of 23 randomised trials (2023), Meta-analysis of 23 placebo-controlled randomised trials, 9,153 patients, with subgrouping by indication: “only dupilumab users with AD but not those with non-AD indications reported an elevated incidence of conjunctivitis” (Source 14)
• FDA-approved DUPIXENT label (DailyMed, revised 4/2026), Pooled safety data from the registration trials for each indication, reported as unadjusted percentages rather than pooled risk ratios: The label reports conjunctivitis rates above placebo in prurigo nodularis (4% vs 1%), nasal polyps (2% vs 1%), COPD (1.4% vs 1%) and bullous pemphigoid (7.5% vs 0%), while agreeing it is similar to placebo in asthma and urticaria and absent in eosinophilic oesophagitis: “Among subjects with asthma, the frequencies of conjunctivitis and keratitis were similar between DUPIXENT and placebo.” (Source 20)

How much

• Reference intake: There is no dietary reference intake for dupilumab; it is a prescription biologic given by subcutaneous injection and the dose is set by the prescriber according to the condition, age and body weight. As a position, the US label (DailyMed, revised 4/2026) gives an adult atopic dermatitis dose of 600 mg as two 300 mg injections, then 300 mg every 2 weeks. (Source 21)
• Upper limit: No upper limit is set by a nutrition body and the label does not define a maximum dose in the usual sense; the approved regimens are fixed by indication and weight band. The SOLO-CONTINUE trial tested going in the other direction – lengthening the interval – and found response fell away, which is why the label's long-term recommendation stays at 300 mg every 2 weeks for adult eczema. (Source 18)
• Studied: The eczema trials gave 300 mg subcutaneously either weekly or every other week for 16 weeks. (Source 2)
• Studied: The asthma trial gave 200 mg or 300 mg every 2 weeks as add-on therapy for 52 weeks. (Source 3)
• Studied: The eosinophilic oesophagitis trial gave 300 mg weekly, or 300 mg every 2 weeks in a separate part of the trial. (Source 5)
• Studied: The COPD and prurigo nodularis trials both gave 300 mg every 2 weeks. (Source 7)

A common belief, and what the research shows

The belief: Dupilumab is an immunosuppressant like a steroid or a transplant drug, so it carries the same infection and cancer risks.

What the research shows: It is not a broad immunosuppressant. It blocks one receptor used by two cytokines, IL-4 and IL-13, and the label describes it as inhibiting “IL-4 signaling via the Type I receptor and both IL-4 and IL-13 signaling through the Type II receptor.” There is no boxed warning on the DUPIXENT label. The infection signal that does exist is narrow and mechanistic rather than general: because IL-4 and IL-13 help control parasites, worm infections were reported more often in treated children, and the label says “Treat patients with pre-existing helminth infections before initiating therapy with DUPIXENT.” The characteristic harms are eye inflammation and injection-site reactions, not opportunistic infection or lymphoma. Live vaccines are nonetheless avoided during treatment because the effect on them is unknown.

Questions and answers

What is it?

Dupilumab is a manufactured antibody, given as an injection under the skin. It belongs to the same family of molecules as the antibodies your own immune system makes – specifically a human IgG4 antibody – and it is engineered to grab one target: the alpha subunit of the interleukin-4 receptor. It is not a steroid, not a chemotherapy drug and not a general immune suppressant. (Source 1)

What does it do in the body?

Two inflammatory signals, IL-4 and IL-13, both need the same receptor component to deliver their message. Dupilumab plugs that component, so neither gets through. The result is less of the specific kind of inflammation called “type 2” – fewer activated mast cells, basophils and eosinophils, less IgE, less mucus from goblet cells. That single blockade explains why one drug helps eczema, asthma, nasal polyps, eosinophilic oesophagitis, itchy nodules and a form of COPD. (Source 1)

Is it good or bad for you?

On balance good for the conditions it is approved for, with one consistent downside. The benefits are large and reproducible: 38% versus 10% clear skin in eczema, exacerbations roughly halved in asthma, 60% versus 5% histological remission in eosinophilic oesophagitis. The main cost is eye inflammation, which in eczema trials ran at 10% versus 2% on placebo and in a meta-analysis was two and a half times more likely in eczema patients. Injection-site reactions are common and mild. There is no boxed warning. Rarely, the eye problems have been severe enough to need surgery. (Source 14)

How do you get more of it?

Dupilumab exists only as a prescription injection; there is no food, supplement or behaviour that produces it. It is given under the skin, and the approved regimens are fixed by condition, age and weight rather than titrated. As a record of what the regulator approved, the adult eczema regimen in the April 2026 US label is a 600 mg start then 300 mg every 2 weeks. This is not a dose for a reader to act on. (Source 21)

If it is harmful, what reduces it?

There is no antidote and no way to speed its removal; the only route is to stop injecting and wait. Because it is an antibody it is broken down slowly into amino acids, and after the last dose the median time to an undetectable level is 9 to 13 weeks in adults and adolescents, longer in young children. That slow washout is why side effects such as eye inflammation are usually managed alongside continued treatment, with ophthalmology input, rather than resolving the moment the drug is stopped. (Source 13)

Why might someone be low in it or missing it?

This question does not really apply: dupilumab is not something the body makes or needs, so nobody is “low” in it. What can happen is a gap in treatment – missed injections, or an interval stretched too far. The randomised withdrawal trial showed that matters: people who had responded well and were then moved to every 4 or 8 weeks, or to placebo, lost ground compared with those who kept going fortnightly. (Source 18)

Which whole foods contain it or feed it?

No whole food contains dupilumab or anything that acts on the IL-4 receptor the way it does, and nothing in food feeds it. Food matters less here than for almost any other drug, because dupilumab is a protein broken down by ordinary catabolism rather than by the liver enzymes that food and juice interfere with. A formal study found no clinically significant change in the handling of caffeine, warfarin, omeprazole, metoprolol or midazolam. (Source 10)

What happens if you do not have it?

Not having dupilumab is the normal state and causes nothing by itself. For someone whose disease was being controlled by it, stopping means the disease returning: in the withdrawal trial, placebo and the longest dosing intervals both led to a loss of response, and the trial's conclusion was that the fortnightly regimen is what sustains it. (Source 11)

How can you test for it?

There is no routine blood test for dupilumab levels in ordinary care, and none is needed because dosing is fixed rather than titrated. What can be measured is its effect on type 2 inflammation markers: exhaled nitric oxide (FeNO), total and allergen-specific IgE, eotaxin-3, TARC and periostin all fall, and the suppression is near-maximal within two weeks. These are research and monitoring markers of biological effect, not diagnostic tests, and they do not tell you whether the drug is working for the patient's symptoms. (Source 22)

References

1. DailyMed (US National Library of Medicine) / Regeneron and Sanofi. DUPIXENT (dupilumab) injection — US prescribing information on DailyMed, revised 4/2026 [dup_moa section]. 2026. Read the source
2. The New England journal of medicine. Two Phase 3 Trials of Dupilumab versus Placebo in Atopic Dermatitis.. 2016. PMID 27690741, DOI 10.1056/nejmoa1610020. Read the source
3. The New England journal of medicine. Dupilumab Efficacy and Safety in Moderate-to-Severe Uncontrolled Asthma.. 2018. PMID 29782217, DOI 10.1056/nejmoa1804092. Read the source
4. Lancet (London, England). Efficacy and safety of dupilumab in patients with severe chronic rhinosinusitis with nasal polyps (LIBERTY NP SINUS-24 and LIBERTY NP SINUS-52): results from two multicentre, randomised, double-blind, placebo-controlled, parallel-group phase 3 trials.. 2019. PMID 31543428, DOI 10.1016/s0140-6736(19)31881-1. Read the source
5. The New England journal of medicine. Dupilumab in Adults and Adolescents with Eosinophilic Esophagitis.. 2022. PMID 36546624, DOI 10.1056/nejmoa2205982. Read the source
6. Nature medicine. Dupilumab in patients with prurigo nodularis: two randomized, double-blind, placebo-controlled phase 3 trials.. 2023. PMID 37142763, DOI 10.1038/s41591-023-02320-9. Read the source
7. The New England journal of medicine. Dupilumab for COPD with Type 2 Inflammation Indicated by Eosinophil Counts.. 2023. PMID 37272521, DOI 10.1056/nejmoa2303951. Read the source
8. DailyMed (US National Library of Medicine) / Regeneron and Sanofi. DUPIXENT (dupilumab) injection — US prescribing information on DailyMed, revised 4/2026 [dup_indications2 section]. 2026. Read the source
9. DailyMed (US National Library of Medicine) / Regeneron and Sanofi. DUPIXENT (dupilumab) injection — US prescribing information on DailyMed, revised 4/2026 [dup_vaccines section]. 2026. Read the source
10. DailyMed (US National Library of Medicine) / Regeneron and Sanofi. DUPIXENT (dupilumab) injection — US prescribing information on DailyMed, revised 4/2026 [dup_cyp section]. 2026. Read the source
11. JAMA dermatology. Efficacy and Safety of Multiple Dupilumab Dose Regimens After Initial Successful Treatment in Patients With Atopic Dermatitis: A Randomized Clinical Trial. [Conclusions and relevance section]. 2020. PMID 31876900, DOI 10.1001/jamadermatol.2019.3617. Read the source
12. DailyMed (US National Library of Medicine) / Regeneron and Sanofi. DUPIXENT (dupilumab) injection — US prescribing information on DailyMed, revised 4/2026 [dup_postmkt_eye section]. 2026. Read the source
13. DailyMed (US National Library of Medicine) / Regeneron and Sanofi. DUPIXENT (dupilumab) injection — US prescribing information on DailyMed, revised 4/2026 [dup_elimination section]. 2026. Read the source
14. Pharmaceutics. Association between Dupilumab and Conjunctivitis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.. 2023. PMID 37111517, DOI 10.3390/pharmaceutics15041031. Read the source
15. DailyMed (US National Library of Medicine) / Regeneron and Sanofi. DUPIXENT (dupilumab) injection — US prescribing information on DailyMed, revised 4/2026 [dup_aetable section]. 2026. Read the source
16. The British journal of dermatology. Clinical and histopathological characterization of paradoxical head and neck erythema in patients with atopic dermatitis treated with dupilumab: a case series.. 2020. PMID 31749159, DOI 10.1111/bjd.18730. Read the source
17. DailyMed (US National Library of Medicine) / Regeneron and Sanofi. DUPIXENT (dupilumab) injection — US prescribing information on DailyMed, revised 4/2026 [dup_asthma_ae section]. 2026. Read the source
18. JAMA dermatology. Efficacy and Safety of Multiple Dupilumab Dose Regimens After Initial Successful Treatment in Patients With Atopic Dermatitis: A Randomized Clinical Trial.. 2020. PMID 31876900, DOI 10.1001/jamadermatol.2019.3617. Read the source
19. The New England journal of medicine. Two Phase 3 Trials of Dupilumab versus Placebo in Atopic Dermatitis. [Conclusions section]. 2016. PMID 27690741, DOI 10.1056/nejmoa1610020. Read the source
20. DailyMed (US National Library of Medicine) / Regeneron and Sanofi. DUPIXENT (dupilumab) injection — US prescribing information on DailyMed, revised 4/2026 [dup_conj section]. 2026. Read the source
21. DailyMed (US National Library of Medicine) / Regeneron and Sanofi. DUPIXENT (dupilumab) injection — US prescribing information on DailyMed, revised 4/2026 [dup_dosing section]. 2026. Read the source
22. DailyMed (US National Library of Medicine) / Regeneron and Sanofi. DUPIXENT (dupilumab) injection — US prescribing information on DailyMed, revised 4/2026 [dup_pd section]. 2026. Read the source