Chronic Urticaria: Antihistamines, Omalizumab & Remibrutinib

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Key takeaways
  • Chronic spontaneous urticaria (CSU) means hives, itch or swelling that recur for more than six weeks without an identifiable trigger. The 2026 international urticaria guideline sets the standard pathway: a second-generation antihistamine at the licensed dose, then a dose increase of up to fourfold, then add-on treatment with omalizumab, with remibrutinib or dupilumab suggested as further options (Zuberbier et al., Allergy 2026).
  • Omalizumab is the best-established add-on. In a phase 3 trial of 323 people whose hives persisted on licensed antihistamines, the 300 mg dose lowered weekly itch scores by 9.8 points at week 12, against 5.1 on placebo (Maurer et al., NEJM 2013). NICE limits NHS use to severe disease that has not responded to antihistamines and leukotriene blockers (NICE TA339).
  • Ligelizumab beat placebo but not omalizumab in two phase 3 trials of 2,057 adults (Maurer et al., Lancet 2024). Novartis then ended its development in CSU for strategic reasons, not safety (ClinicalTrials.gov NCT04210843).
  • Remibrutinib, an oral BTK inhibitor, beat placebo on hive and itch scores at week 12 in two trials of 925 people (Metz et al., NEJM 2025). The US FDA approved it on 30 September 2025, and the European Commission approval was announced on 27 April 2026 (Novartis, FDA; Novartis, EC). Its main label warning is bleeding.
  • Autoimmune links are real but do not change first-line care. The 2026 guideline advises limited first-line tests (blood count, CRP or ESR) and, in specialist care, total IgE and IgG anti-TPO, and advises against intensive, costly screening programmes. A 2017 systematic review found strong evidence that people with CSU have higher IgG antithyroid antibody levels than controls (Kolkhir et al., Allergy 2017). The guideline itself says these markers have no diagnostic-accuracy studies behind them.
  • Vitamin D and probiotics have small, mixed-quality trials. A 2023 randomised trial of 80 people found improvement at both vitamin D doses studied (Nabavizadeh et al., 2023). A 2025 probiotic meta-analysis reported better relief rates when probiotics were added to antihistamines, but the authors say bias limits the findings (Frontiers in Microbiology 2025).
  • Money trail: omalizumab was developed by Genentech and Novartis, and the two companies co-promote it in the US (Novartis). Every pivotal drug trial we reviewed was funded by Novartis or by Genentech and Novartis. The 2026 guideline reports funding from six societies (BSACI, GA2CI, APAAACI, the American Academy of Dermatology, GA²LEN and EDF) and no other source. Its Methods Report says 124 panel members declared no personal financial conflict, so the rest declared at least one, and Novartis is the firm named most often in that table.
  • Evidence grade: Strong for the antihistamine-first pathway and for omalizumab's benefit over placebo. Moderate for remibrutinib, which has two positive, manufacturer-funded trials and approvals in two regions. Weak for vitamin D and probiotics. Insufficient for any autoimmune-directed supplement claim.

Independent evidence review · Prescription medicine

For chronic spontaneous urticaria, the best independent evidence supports a stepwise approach: a standard-dose second-generation antihistamine first, a dose increase second, and omalizumab for people who still have hives. Remibrutinib is a newer oral option with two positive trials, both sponsored by its maker. Autoimmune tests help clinicians look for causes but do not decide treatment on their own, and supplements have only small, weak trials behind them. Our confidence: high for the antihistamine-first pathway and for omalizumab's benefit; moderate for remibrutinib's benefit over the longer term; low for vitamin D, probiotics and any autoimmune-directed supplement.

Best evidence for antihistamines at standard and up-dosed levels as first steps, and omalizumab 300 mg as the best-studied add-on
Main risks bleeding with remibrutinib; more serious adverse events on omalizumab 300 mg in one trial (figures not checked here); antihistamine up-dosing is off-label and untested above fourfold
Key rule treatment changes belong with a clinician or pharmacist; swelling of the lips, tongue or throat, or trouble breathing needs 999 at once
Safety first
Hives with swelling of the lips, mouth, tongue or throat, fast or difficult breathing, a tight throat, or someone who becomes confused, drowsy or faints needs an emergency call to 999 straight away. This article is about a skin condition and does not cover self-harm or depression, so no crisis line applies here.

Table of contents

Evidence summary

Claim Evidence Source Funding / conflict Strength
A second-generation H1 antihistamine at standard dose is first-line for all types of urticaria The guideline recommends it as first-line treatment for all types of urticaria, rated strong consensus with 100% agreement. Zuberbier et al. 2026 Funded by six societies (BSACI, GA2CI, APAAACI, AAD, GA²LEN, EDF); no other funding. 124 panel members declared no personal financial conflict; the rest declared at least one, mostly drug makers. Strong
Raising the antihistamine dose up to fourfold helps when standard doses fail The guideline recommends this as second-line treatment, before other drugs (strong consensus, over 95% agreement), and recommends against going above fourfold. It says the approach is off-label and that doses above fourfold have not been tested. Zuberbier et al. 2026 As above. The guideline does not report a trial of up-dosing. Moderate
Omalizumab reduces itch and hives in people whose symptoms persist on antihistamines Phase 3, n=323: change in weekly itch score at week 12 of -9.8 (300 mg) vs -5.1 (placebo), P<0.001. The 75 mg dose was not significantly different from placebo. Maurer et al., NEJM 2013 Funded by Genentech and Novartis Pharma (NCT01292473). Manufacturer-funded and peer-reviewed. Strong
Ligelizumab is better than omalizumab Two phase 3 trials, n=2,057. Ligelizumab beat placebo but not omalizumab on the primary endpoint (weekly urticaria activity score, UAS7) at week 12. Maurer et al., Lancet 2024 Funded by Novartis Pharma. The negative comparison with omalizumab is against the sponsor's own interest. Strong (against superiority)
Remibrutinib reduces hives and itch versus placebo REMIX-1 (n=470) and REMIX-2 (n=455), randomised 2:1. Change in UAS7 at week 12: -20.0 vs -13.8 (REMIX-1) and -19.4 vs -11.7 (REMIX-2), both P<0.001. Metz et al., NEJM 2025 Funded by Novartis Pharmaceuticals. Two concordant trials, but both sponsor-run and 12-week primary data only. Moderate
Remibrutinib causes bleeding The US label lists a serious bleeding risk, monitoring for bleeding signs, and advice to stop for 3 to 7 days before planned procedures. Novartis FDA release, 2025 Summary from the manufacturer; we did not open the full FDA label in this review. Risk
Autoimmune thyroid antibodies are raised in people with CSU Strong evidence of higher IgG antithyroid antibodies than controls. Most studies reported rates of at least 10%. This is an association, not proof of cause. Kolkhir et al. 2017 Funding statement not retrieved (publisher page blocked to our tools). Authors include Metz and Maurer, who also co-authored Novartis-funded trials. Strong (association)
Intensive, wide screening for causes of CSU is worthwhile The guideline advises against intensive and costly general screening programmes, and recommends limited tests (blood count, CRP or ESR; total IgE and IgG anti-TPO in specialist care). It says no studies assess the accuracy of these markers. Zuberbier et al. 2026 As above. Consensus (against)
Vitamin D supplementation improves CSU symptoms One randomised trial of 80 people (4,200 vs 28,000 IU a week, 12 weeks). A 2025 review of 11 studies (1,491 people) calls for better RCTs. Nabavizadeh et al. 2023; 2025 review 2025 review: "no specific funding" and no competing interests declared. Nabavizadeh trial: no grant listed in the record checked; its conflict statement was not retrieved. Weak
Probiotics improve relief when added to antihistamines 11 trials, 1,014 people. Relief rate odds ratio 2.90 (95% CI 1.97 to 4.28). The authors say risk of bias limits the result. Frontiers in Microbiology 2025 Hunan provincial science, education and university grants; authors declare no commercial or financial relationships. Weak
Ligelizumab is available for CSU Development in CSU was ended by the sponsor. It was never licensed for CSU in the sources reviewed. ClinicalTrials.gov NCT04210843 Novartis Pharmaceuticals, as sponsor. Insufficient

Independent evidence and credibility scorecard

Independence tiers: 1 = regulator or government body; 2 = academic or Cochrane team with no declared commercial funding for the work; 3 = independent authors analysing mostly manufacturer-run trials, or minor declared industry ties; 4 = manufacturer-funded or manufacturer-authored. Credibility runs from A (highest) to D.

Source Who funds it Country Independence tier (1–4) Credibility (A–D) Why it would tell the truth / residual bias
NICE TA339 (2015) UK public body (NICE), which is funded by the state. The appraisal used the manufacturer's submission, and there is a commercial access agreement with a discount. UK 1 A− A statutory body that answers to NHS budgets, so it rewards cost-effectiveness rather than sales. Residual bias: the evidence base came from the manufacturer's submission. NICE records a 2018 review that found nothing new.
NHS hives advice page UK public health service UK 1 B A public service with no product to sell and a duty to be accurate. It is patient guidance, not a graded evidence review, and its review date was not checked.
Tuchinda et al. 2018, vitamin D systematic review No specific grants; authors declare no competing interests (Clin Transl Allergy 2018) Thailand 2 B Academic team in Thailand; no commercial tie found in the record checked. Incentive is publication and academic standing. Residual bias: small studies.
Vitamin D systematic review, 2025 "The authors received no specific funding"; "no competing interests" declared (Eur J Med Res 2025) Afghanistan (author affiliation: Ibn E Seena Hospital, Kabul) 2 B Hospital-based authors with no declared funder, so nobody pays for a particular answer; the incentive is publication. Residual bias: heterogeneous designs and doses across 11 studies, and the authors call for RCTs.
Nabavizadeh et al. 2023, vitamin D RCT No grant listed in the record checked; conflict statement not retrieved Iran (Allergy Research Center, Shiraz University of Medical Sciences, and Namazi Hospital, Shiraz) 2 B University allergy research centre with no declared sponsor. Residual bias: 80 participants, and a small study may overstate effects.
Probiotic meta-analysis, 2025 Natural Science Foundation of Hunan Province, a Hunan TCM research project, Hunan Education Department and Hunan University of Chinese Medicine grants; no competing interests declared China 2 B University-based team in China; funded by Hunan public grants. The authors grade the certainty of evidence and call the risk of bias a limit. Residual bias: the lead authors sit in a traditional Chinese medicine school, and a positive result would help the academic programmes that funded it.
International urticaria guideline (Zuberbier et al., Allergy 2026) Six medical societies (BSACI, GA2CI, APAAACI, American Academy of Dermatology, GA²LEN, EDF); no other funding, and some societies paid delegates' travel. 124 panel members declared no personal financial conflict; the rest declared some. Conflicted members were barred from voting on related topics. Multinational (213 experts nominated by 107 societies from 59 countries; lead author in Berlin, Germany) 3 B Methods follow Cochrane and GRADE, which constrain bias. Residual bias: societies' own income can depend on industry sponsorship, and the Methods Report table names many drug makers, with Novartis named most often. Its up-dosing advice is consensus-based, and its remibrutinib advice rests on sponsor-run trials.
Kolkhir et al. 2017, thyroid systematic review Funding statement not retrieved (publisher page blocked to our tools). Authors include Metz and Maurer. Germany and Russia (Charité Berlin; Sechenov University, Moscow) 3 B A systematic review of observational studies, not a sponsor trial. Residual bias: its authors work in the same field as the manufacturer trials, and the review mixes strong, weak and inconsistent findings from mostly observational studies.
Omalizumab phase 3, NEJM 2013 Genentech and Novartis Pharma (NCT01292473) US and Switzerland (Genentech and Novartis) 4 C Peer-reviewed in a leading journal, but the sponsor's product is the subject. Incentive is to show benefit. Residual bias: the trial was short (12 weeks primary, 16-week follow-up).
Ligelizumab phase 2b, NEJM 2019 Novartis Pharma (NCT02477332) Switzerland (Novartis) 4 C Sponsor-run dose-finding study. Residual bias: small and short (382 randomised, 20 weeks). It was a positive step that the sponsor later tested in phase 3.
PEARL-1 and PEARL-2, Lancet 2024 Novartis Pharma AG (NCT03580369; NCT03580356), and Europe PMC also lists Charles Sturt University (Australia) as a funder; we could not retrieve the funding statement to see what it supported Switzerland (Novartis) 4 C Sponsor-run, but the headline result was negative against its own comparator (omalizumab), which a sponsor has little reason to report. Residual bias: the sponsor wrote the paper and ran the trial.
REMIX-1 and REMIX-2, NEJM 2025 Novartis Pharmaceuticals (NCT05030311; NCT05032157) Switzerland (Novartis) 4 C Two concordant, placebo-controlled trials with clear primary endpoints. Residual bias: the sponsor designed, ran and funded both trials, and the trials cover only 12 weeks in the primary report.

Where opposing interests converge. The sponsor-run PEARL trials reported no advantage of ligelizumab over omalizumab, and the guideline and NICE both place omalizumab as the next step after antihistamines. That agreement is the strongest signal in this review. Country clustering. Most drug trials and both company releases come from Novartis or Genentech, based in Switzerland and the US. The guideline's experts came from 59 countries, but it is an initiative of GA²LEN and the European Dermatology Forum run from Berlin. Both NICE and the NHS sources are UK-based. Their lens is the UK health system and budget.

What chronic spontaneous urticaria is, and its legal status

CSU is hives, itch or swelling that recur for more than six weeks without an identifiable trigger. The remibrutinib trial paper defines it as an idiopathic syndrome with recurring itch, hives or angioedema for more than six weeks (Metz et al., NEJM 2025). The guideline classifies urticaria by duration: acute when it lasts six weeks or less, chronic beyond that. It separates CSU from chronic inducible urticaria, where a trigger such as cold, heat or pressure can be identified. Within CSU, the guideline also distinguishes forms with type I autoimmunity (autoallergy), type IIb autoimmunity and an unknown cause (Zuberbier et al. 2026).

CSU is not the same condition as urticarial vasculitis, in which hives are caused by inflamed blood vessels. That condition has its own article: urticarial vasculitis and HUVS.

Drugs with licences

  • Second-generation H1 antihistamines are the first-line treatment in the guideline. They are sold over the counter in many countries, and the licensed dose is the starting point (Zuberbier et al. 2026). Up-dosing is off-label in the guideline's own wording.
  • Dupilumab is described in the 2026 guideline as approved for urticaria in the USA, UAE, Brazil and Japan at the time of writing. The guideline suggests it as an add-on, with a weaker consensus (over 75% agreement) than for omalizumab (Zuberbier et al. 2026). We did not verify a regulator page for it.
  • Omalizumab (Xolair) was approved by the FDA on 21 March 2014 for chronic idiopathic urticaria in people aged 12 and over whose hives persist on H1 antihistamines (Novartis release). In England it is available only under NICE TA339 (2015), which sets strict criteria (NICE).
  • Remibrutinib (Rhapsido) was approved by the FDA on 30 September 2025 for adults with CSU who remain symptomatic on H1 antihistamines. The European Commission approved it for the same group, and Novartis announced the approval on 27 April 2026 (Novartis, FDA; Novartis, EC). The UK MHRA granted marketing authorisation to Novartis Pharmaceuticals UK Limited on 5 August 2026, for adults with CSU not adequately controlled by antihistamines (MHRA press release).
  • Ligelizumab has no licence for CSU. Its development in CSU was ended by the sponsor (ClinicalTrials.gov).

How it works

Hives occur when a trigger causes the skin to release histamine and other chemicals (NHS). Omalizumab is an anti-IgE antibody that targets IgE and affects mast cell and basophil function (Maurer et al., NEJM 2013). Ligelizumab was designed as a higher-affinity anti-IgE antibody (Maurer et al., NEJM 2019). Remibrutinib is an oral, highly selective Bruton's tyrosine kinase (BTK) inhibitor (Metz et al., NEJM 2025). We did not open a source that explains its effect on mast cells in detail, so we do not describe that mechanism further.

What is proven in people: the clinical benefit of omalizumab, ligelizumab and remibrutinib on hive and itch scores, measured in phase 2 and 3 trials. What is not settled: why CSU starts in the first place, and how far autoimmunity drives it. The guideline calls the autoimmune mechanisms a subtype and does not claim a single cause. Many mechanistic claims in supplement marketing rest on lab or animal work, and we did not find human trials that test those mechanisms directly.

What works and what does not

Option What the evidence shows Verdict
Standard-dose second-generation antihistamine First-line in the guideline; strong consensus. Symptom benefit is usual, but control is not complete for everyone. Works (first line)
Antihistamine up-dosing to fourfold Second-line in the guideline by consensus. Off-label, and doses above fourfold have not been tested. Mixed (consensus, off-label)
Omalizumab (add-on) Phase 3 benefit over placebo at 300 mg. NICE restricts NHS use to severe, antihistamine-refractory disease. Works (second line)
Remibrutinib (oral add-on) Two positive phase 3 trials; FDA and EC approved. Works (newer option)
Ligelizumab No advantage over omalizumab; development ended in CSU. Insufficient (no current route)
Vitamin D Small trials and reviews; authors call for better RCTs. Insufficient (weak trials)
Probiotics Meta-analysis suggests benefit with antihistamines, but risk of bias is high. Mixed (promising, weak)
Intensive autoimmune or infection screening The 2026 guideline advises against intensive, costly general screening and recommends limited tests. Not advised (consensus)

Benefits by claim

Do higher antihistamine doses help?

The guideline recommends up-dosing a second-generation antihistamine up to fourfold in people who do not respond to the standard dose, before other treatments (Zuberbier et al. 2026). It rates this as strong consensus (over 95% agreement), based on studies of up to fourfold doses of several antihistamines rather than a single dose-response trial. The guideline says no serious adverse event has been reported in the literature linked to long-term intake. It also says doses above fourfold have not been tested and recommends against them.

Does omalizumab work when antihistamines fail?

Yes, in trials. In the phase 3 trial of 323 people, weekly itch scores fell by 9.8 points at week 12 with 300 mg, against 5.1 on placebo. The 150 mg dose gave 8.1 points, and the 75 mg dose did not differ from placebo (P=0.46) (Maurer et al., NEJM 2013). The 2026 guideline recommends omalizumab as add-on for people unresponsive to high-dose antihistamines (strong consensus, over 95% agreement), at 300 mg every 4 weeks to start. NICE asks for severe disease, for example a weekly urticaria activity score of 28 or more, after antihistamines and leukotriene blockers have failed (NICE TA339).

Is ligelizumab better than omalizumab?

No. In the two phase 3 PEARL trials, 72 mg of ligelizumab beat placebo by 8.0 points on the UAS7 score in PEARL-1 and 10.0 points in PEARL-2 at week 12. Against omalizumab the difference was 0.7 points in PEARL-1 and 0.4 points in PEARL-2, with confidence intervals crossing zero (Maurer et al., Lancet 2024). The earlier phase 2b trial had shown a dose-response and a 51% hive-control rate at 72 mg, but it was small and short (Maurer et al., NEJM 2019). The registry protocol dates the sponsor’s decision to stop CSU development to 6 April 2022 (ClinicalTrials.gov NCT04210843).

Does remibrutinib work, and how quickly?

In REMIX-1 and REMIX-2, people randomised to remibrutinib 25 mg twice daily lowered their weekly UAS7 by 20.0 and 19.4 points at week 12, against 13.8 and 11.7 on placebo. At week 12, 46.8% of remibrutinib users in REMIX-2 had a UAS7 of 6 or lower, against 19.6% on placebo (REMIX-1: 49.8% against 24.8%). A UAS7 of 0 was reached by 31.1% and 27.9%, against 10.5% and 6.5% (Metz et al., NEJM 2025). The 2026 guideline suggests remibrutinib as an add-on for people unresponsive to high-dose antihistamines (consensus, over 75% agreement) and says it can be considered in all CSU, especially after high-dose antihistamine and omalizumab have failed. The Novartis release gives no effect sizes beyond this, and says that about a third of patients on remibrutinib had complete absence of itch and hives at week 12 (Novartis, FDA).

Do vitamin D or probiotics help?

Possibly, but the evidence is weak. In the 2023 randomised trial of 80 people, both 4,200 IU a week and 28,000 IU a week of vitamin D3 for 12 weeks improved urticaria severity, and the higher dose gave greater improvement in quality of life and vitamin D levels (the abstract reports the higher dose was significantly better at week 6 for the severity score, and at weeks 6 and 12 for quality of life) (Nabavizadeh et al. 2023). A 2025 systematic review of 11 studies (1,491 people) found most studies showed lower vitamin D in CSU, and it calls for more high-quality RCTs (2025 review). The 2018 review found lower vitamin D in most studies, but it calls this association evidence, not proof of cause (Tuchinda et al. 2018).

For probiotics, a 2025 meta-analysis of 11 trials with 1,014 participants found a higher relief rate with antihistamines plus probiotics than with antihistamines alone (odds ratio 2.90). The authors say risk of bias in the included trials means the findings need confirmation in high-quality trials (Frontiers in Microbiology 2025). The 2026 guideline says gut microbiome changes might play a role in urticaria and that probiotics could open new avenues, but it makes no recommendation on them.

Do autoimmune tests change treatment?

Not on their own. The 2017 systematic review found strong evidence of a link between CSU and raised IgG antithyroid antibodies, with most studies reporting rates of at least 10%. It also found higher rates of thyroid dysfunction in CSU. Its abstract also rates as strong evidence that CSU can improve with levothyroxine or other thyroid drugs, although this is a review of mostly observational studies and says nothing about people without thyroid disease (Kolkhir et al. 2017). The 2026 guideline recommends limited first tests (blood count, CRP and/or ESR) and, in specialist care, total IgE and IgG anti-TPO. It says these markers are linked to autoimmune subtypes but that their usefulness is limited because no studies assess their diagnostic accuracy, and that intensive, costly general screening is not advised (Zuberbier et al. 2026).

For clinicians
Refer to a specialist when control is poor. The 2026 guideline recommends limited first tests and further tests guided by history, especially in long-standing or uncontrolled disease. Treatment changes, including omalizumab and remibrutinib, need a specialist's assessment. NICE criteria for omalizumab apply in England (Zuberbier et al. 2026; NICE TA339).

Risks and all side effects

Bleeding warning: remibrutinib
The US label describes a serious risk of bleeding. Patients are monitored for signs of bleeding, and the risk may be higher with blood-thinning drugs. Providers may advise stopping for 3 to 7 days before and after planned procedures or surgery (Novartis, FDA release). The full safety results were not checked in this review (Metz et al., NEJM 2025).

Omalizumab

The full 2013 safety table was not checked in this review (Maurer et al., NEJM 2013). We did not open the current omalizumab label in this review, so its full warnings list is not reproduced here. Read the current label or ask a clinician.

Antihistamine up-dosing

The guideline reports no serious adverse events attributed to long-term up-dosing in the literature. It also notes that the approach is off-label and that doses above fourfold have not been tested. The guideline also describes a Taiwanese population study that linked higher cumulative antihistamine doses to dementia risk. It judged the study not robust enough to change its advice, noted that an unpublished analysis did not confirm it, and called it a safety signal needing further monitoring. Sedation and other effects vary by drug. Ask a pharmacist before changing dose (Zuberbier et al. 2026).

When hives are an emergency

The NHS advice page lists the emergency signs: sudden swelling of the lips, mouth, throat or tongue; very fast or difficult breathing; a tight throat or difficulty swallowing; blue, grey or pale skin, lips or tongue; or sudden confusion, drowsiness or fainting. It says that swollen or itchy rashes with these signs may be a serious allergic reaction needing hospital care. It also advises a GP or NHS 111 if symptoms do not improve after 2 days, or if the rash is spreading or keeps coming back (NHS).

All interactions

  • Blood thinners and remibrutinib. The label says bleeding risk may be higher with anticoagulants or antiplatelet drugs (Novartis, FDA release).
  • Live vaccines. The label advises avoiding live or live-attenuated vaccines during remibrutinib treatment (same source).
  • Surgery and procedures. Stopping for 3 to 7 days before and after procedures is advice from prescribers, not a dosing rule (same source).
  • Antihistamine combinations. We did not verify a current list of antihistamine interactions beyond the guideline's general advice. A pharmacist can check your full medicine list.

Who should avoid it, or take extra care

  • Pregnancy and breastfeeding. The remibrutinib label says it is not known whether the drug harms an unborn baby or passes into breast milk, and advises talking to a healthcare provider about the pregnancy exposure registry if pregnancy occurs (Novartis, FDA). We did not open the omalizumab pregnancy advice, so check the current label.
  • Children. The remibrutinib label says safety and effectiveness in children are not established. NICE recommends omalizumab only from age 12 (NICE TA339). For children, the guideline gives separate antihistamine choices by age (Zuberbier et al. 2026).
  • People with a bleeding problem or on blood thinners. The remibrutinib label flags a higher bleeding risk with blood thinners, so a specialist should review this before treatment starts (see the bleeding warning above).
  • People due for surgery or procedures. The label advice on stopping for 3 to 7 days is a point to plan with the surgical team.
  • People who need live vaccines. The remibrutinib label advises avoiding them during treatment (see interactions above).

Doses studied and how they are given

These are doses used in trials or stated on official labels, framed as "doses studied" and "label dose". They are not personal instructions.

  • Antihistamines. Standard licensed dose first; the guideline's second-line option is up-dosing up to fourfold, which is off-label (Zuberbier et al. 2026).
  • Omalizumab. Subcutaneous doses of 75, 150 or 300 mg given every 4 weeks for three injections in the trial (Maurer et al. 2013). NICE limits treatment to six doses and stops it if there is no response by the fourth dose (NICE TA339).
  • Ligelizumab. Subcutaneous 72 mg or 120 mg every 4 weeks in the phase 3 trials (Maurer et al. 2024). This is not an approved regimen for CSU.
  • Remibrutinib. 25 mg by mouth twice daily in the phase 3 trials (Metz et al. 2025). The EC release says the treatment is taken without any lab monitoring (Novartis, EC release).
  • Vitamin D. Trial doses of 4,200 IU a week and 28,000 IU a week for 12 weeks (Nabavizadeh et al. 2023). The 2025 review describes 4,000 IU a day or 60,000 IU a week as higher-dose regimens (2025 review).

Follow the money: who makes it and who funded the evidence

Who makes and sells these drugs

Omalizumab (Xolair) was developed jointly by Genentech and Novartis Pharma AG. Novartis Pharmaceuticals Corporation co-promotes it with Genentech in the US (Novartis release). We did not read Roche’s 2024 half-year report in this check, so we state no Xolair sales figure.

Remibrutinib (Rhapsido) is a Novartis product. Its company releases describe FDA approval on 30 September 2025 and an EC approval announced on 27 April 2026 (Novartis, FDA; Novartis, EC). These are company statements, and we treat them as marketing-grade (tier 4) for product claims.

Ligelizumab was a Novartis product. The company ended its development in CSU in a registry entry that gives a strategic reason and no safety reason (ClinicalTrials.gov NCT04210843).

Market size. We did not find a citable market-size figure for CSU drugs, so we do not state one.

Who funded the trials and the guideline

  • Omalizumab phase 3, NEJM 2013: funded by Genentech and Novartis Pharma (NCT01292473). Tier 4.
  • Ligelizumab phase 2b, NEJM 2019: funded by Novartis Pharma (NCT02477332). Tier 4.
  • PEARL-1 and PEARL-2, Lancet 2024: Novartis Pharma AG (NCT03580369; NCT03580356), and Europe PMC also lists Charles Sturt University (Australia) as a funder; we could not retrieve the funding statement to see what it supported. Tier 4.
  • REMIX-1 and REMIX-2, NEJM 2025: funded by Novartis Pharmaceuticals (NCT05030311; NCT05032157). Tier 4.
  • The international guideline, Allergy 2026: funded by the British Society for Allergy & Clinical Immunology, Gulf Academy of Allergy and Clinical Immunology, Asia Pacific Association of Allergy, Asthma and Clinical Immunology, American Academy of Dermatology, GA²LEN and European Dermatology Forum, with no other funding source; some societies paid delegates’ travel. Its Methods Report says 124 panel members declared no personal financial conflict (59.05% there; 58.21% in the paper, which counts 213 members). Other members declared payments from drug makers: Novartis is the company named most often in the table, followed by Sanofi, and Celltrion, AbbVie and Takeda also appear. Members with a relevant conflict, and employees of companies with a product at issue, were excluded from voting on related recommendations (Zuberbier et al. 2026).
  • Kolkhir et al. 2017: funding statement not retrieved (the publisher page was blocked to our tools). Its authors are Kolkhir, Metz, Altrichter and Maurer (Kolkhir et al. 2017).
  • Vitamin D and probiotic studies: no industry funding identified. The 2025 vitamin D review reports no specific funding and no competing interests (Siddiqui et al. 2025). The probiotic meta-analysis was supported by Hunan provincial and university grants, and its authors declare no commercial relationships (Frontiers in Microbiology 2025).

Documented integrity events

We did not find a regulator sanction, warning letter or recall for omalizumab, ligelizumab or remibrutinib in the sources reviewed. The NICE appraisal records a commercial access agreement that includes a discount for omalizumab, but the guidance does not name the amount (NICE TA339). That is a pricing arrangement, not evidence of misconduct. We did not search for lawsuits or recalls beyond these sources.

Follow the money

Research funding at a glance

Funding & backersSource & studyClaim & limits

12 sources graded. The counts below are the independence tiers assigned in the scorecard above. They count sources, not funding amounts or evidence quality.

Tier 12Independent
Tier 24Indirect ties
Tier 32Interested party
Tier 44Self-interested

Public funding alone does not prove independence, and commercial funding alone does not prove a claim false. Named funders, countries and relationships are in the scorecard and source notes.

Frequently asked questions

What counts as chronic spontaneous urticaria?

Hives, itch or swelling that recur for more than six weeks with no identifiable trigger. The remibrutinib trial paper uses this definition (Metz et al., NEJM 2025), and the guideline classifies urticaria as chronic beyond six weeks (Zuberbier et al. 2026).

Can the antihistamine dose be raised?

The guideline recommends up-dosing a second-generation antihistamine up to fourfold when the standard dose fails. It calls this off-label, says higher doses have not been tested and recommends against them. Ask a prescriber or pharmacist before changing a dose (Zuberbier et al. 2026).

Is omalizumab a last resort?

It is the next step after antihistamines in the 2026 guideline, and in England NICE allows it only for severe disease that has not responded to antihistamines and leukotriene blockers (NICE TA339).

Does remibrutinib replace injections?

Remibrutinib is an oral tablet taken twice daily. Novartis says it needs no lab monitoring (Novartis, EC release). It carries a bleeding warning and is not established in pregnancy or children (Novartis, FDA release).

Which blood tests are needed?

The 2026 guideline recommends limited first tests (blood count, CRP and/or ESR) and, in specialist care, total IgE and IgG anti-TPO, with more only as history suggests. Ask a clinician which tests apply to you (Zuberbier et al. 2026).

Does thyroid disease cause hives?

The link is well documented as an association. A 2017 systematic review found strong evidence of higher IgG antithyroid antibodies in CSU, but it does not prove that thyroid disease causes hives (Kolkhir et al. 2017).

Do vitamin D or probiotics cure hives?

We found no evidence that they cure CSU. Vitamin D and probiotics have small trials with mixed quality. The 2023 vitamin D trial enrolled 80 people, and the 2025 probiotic meta-analysis reports results with high risk of bias (Nabavizadeh et al. 2023; Frontiers in Microbiology 2025). Neither replaces standard treatment.

When should hives be treated as an emergency?

Call 999 at once for swelling of the lips, mouth, throat or tongue, fast or difficult breathing, a tight throat, or sudden confusion, drowsiness or fainting. The NHS advice page lists these signs (NHS).

Sources and funding notes

What we could not verify: the 2026 guideline text was read in full through Europe PMC, but its evidence report was not opened, so we rely on the guideline's own summaries of the up-dosing, omalizumab and remibrutinib evidence. We counted company names in the Methods Report conflict table by text extraction, so the ranking of firms is approximate, and the paper (58.21%) and the Methods Report (59.05%) give slightly different percentages for members with no personal financial conflict. Also not verified: the 2013 omalizumab safety table; the full remibrutinib and omalizumab prescribing information (the remibrutinib label was checked for bleeding, pregnancy, lactation, paediatric and vaccine statements); the Roche and Genentech ownership link and any Xolair sales figure, which we dropped; the funding statements of Kolkhir et al. 2017, the Lancet PEARL paper (including what Charles Sturt University funded) and the Nabavizadeh trial, whose publisher pages were blocked to our tools; and any regulator page for dupilumab. We found no source supporting specific "autoimmune urticaria" supplement marketing claims, so we treat those claims as unverified rather than false. Herbal and traditional Chinese medicine reviews were found but not opened, so they receive no grade.

  1. Zuberbier T, et al. The International Guideline for the Definition, Classification, Diagnosis and Management of Urticaria. Allergy 2026;81(8):2582-2632, doi 10.1111/all.70210 — funded by six societies; Methods Report lists panel conflicts of interest. It updates the 2022 guideline.
  2. NICE TA339: omalizumab for previously treated chronic spontaneous urticaria (2015) — government appraisal body; based on the manufacturer's submission; commercial access agreement.
  3. NHS: hives — public health advice; review date not checked.
  4. Maurer M, et al. Omalizumab for the treatment of chronic idiopathic or spontaneous urticaria. N Engl J Med 2013 — phase 3 trial; funded by Genentech and Novartis Pharma.
  5. Maurer M, et al. Ligelizumab for chronic spontaneous urticaria. N Engl J Med 2019 — phase 2b trial; funded by Novartis Pharma.
  6. Maurer M, et al. Efficacy and safety of ligelizumab in adults and adolescents with chronic spontaneous urticaria: two phase 3 trials. Lancet 2024 — PEARL-1 and PEARL-2; funded by Novartis Pharma.
  7. Metz M, et al. Remibrutinib in chronic spontaneous urticaria. N Engl J Med 2025 — REMIX-1 and REMIX-2; funded by Novartis Pharmaceuticals.
  8. ClinicalTrials.gov NCT04210843 — registry record; sponsor Novartis Pharmaceuticals; terminated for a strategic decision not based on safety.
  9. Novartis: FDA approval of Rhapsido (remibrutinib), 30 September 2025 — manufacturer release; sponsor's own statement.
  10. Novartis: European Commission approval of Rhapsido, announced 27 April 2026 — manufacturer release.
  11. UK MHRA: approval of Rhapsido (remibrutinib), granted 5 August 2026, Novartis UK release dated 6 August 2026 — regulator.
  12. Novartis: FDA approval of Xolair for chronic idiopathic urticaria, 21 March 2014 — manufacturer release; co-promotion with Genentech.
  13. Tuchinda P, et al. Relationship between vitamin D and chronic spontaneous urticaria: a systematic review. Clin Transl Allergy 2018 — academic review; Siriraj Hospital, Thailand; no grants, no competing interests.
  14. Chronic urticaria and vitamin D supplementations: a systematic review, 2025 — academic review; Ibn E Seena Hospital, Kabul, Afghanistan; no specific funding and no competing interests declared.
  15. Nabavizadeh SH, et al. The effect of vitamin D add-on therapy on the improvement of quality of life and clinical symptoms of patients with chronic spontaneous urticaria. Asian Pac J Allergy Immunol 2023 — randomised trial; Allergy Research Center and Namazi Hospital, Shiraz University of Medical Sciences, Iran; no grant listed in the record checked.
  16. Efficacy and safety of probiotics as a complementary treatment for urticaria: systematic review and meta-analysis. Front Microbiol 2025 — academic meta-analysis; Hunan University of Chinese Medicine, Changsha, China; Hunan provincial and university grants; no commercial conflicts declared.
  17. Kolkhir P, et al. Comorbidity of chronic spontaneous urticaria and autoimmune thyroid diseases: a systematic review. Allergy 2017 — systematic review; Charité Berlin and Sechenov University Moscow authors; funding statement not retrieved (publisher page blocked).

Educational research reviewed 9 October 2026. This article is not medical advice; talk to a qualified clinician or pharmacist before starting, stopping or combining treatments.

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