Xolair injection is only FDA approved for treating allergic asthma, nasal polyps, and chronic urticaria, and is currently not approved to treat allergies. However, there is good evidence to show that it may be helpful for allergic rhinitis or in addition to some immunotherapy desensitizing treatments and fair or weak evidence for some other allergic conditions. In Japan, Xolair is also approved to treat severe Japanese cedar pollinosis (JC) a form of seasonal allergic rhinitis that affects 38.8% of the Japanese population.

Is Xolair effective for allergies?

There are varying levels of evidence to show Xolair (omalizumab) is effective for the following allergies or allergic conditions, but it is currently not FDA approved to treat these.

Xolair for Allergic Rhinitis

There is good evidence to support the use of omalizumab for allergic rhinitis. An RCT evaluated 536 ragweed-allergic patients with different dosages of omalizumab (50, 150, and 300 mg) or placebo (an inactive treatment) every 3–4 weeks just before and during ragweed season. Patients treated with 300 mg of omalizumab had fewer rhinitis symptoms better quality of life scores than the other groups and did not decline during the peak ragweed season. A follow-up study reported that the therapy is well tolerated without any significant immunologic reactions. Further studies have reported omalizumab to be effective at reducing symptoms and rescue medication usage in patients with allergic rhinitis to ragweed, birch, cedar, and perennial allergens.
A meta-analysis published evaluated 2,870 patients treated for seasonal or perennial allergic rhinitis and reported omalizumab significantly reduced both daily nasal symptoms and daily nasal rescue medication usage. No significant adverse events were reported.

Xolair for Allergen immunotherapy (inhalants)

There is good evidence to support the use of omalizumab in people undergoing allergen immunotherapy in addition to standard maintenance-dose immunotherapy. In 221 pediatric patients sensitized to birch and grass pollen, the addition of omalizumab reduced symptoms by 48% compared to birch immunotherapy alone. Similar results were seen in grass season, with a 57% decrease in symptoms and significantly reduced rescue medication with the addition of Xolair to grass immunotherapy compared to grass immunotherapy alone. In another study looking at patients allergic to ragweed, the combination of omalizumab and immunotherapy showed a significant improvement in severity scores during the ragweed season compared with those receiving immunotherapy alone after rush immunotherapy build-up. Combined treatment with omalizumab and immunotherapy is more effective than omalizumab or immunotherapy alone.
In addition, the addition of omalizumab to immunotherapy decreased the risk of anaphylaxis caused by immunotherapy fivefold and resulted in fewer systemic reactions in asthma patients.

Xolair for Atopic Dermatitis

Several case series have investigated using omalizumab for atopic dermatitis (AD) but results have been mixed and evidence is considered fair to support its use. One small case series of 7 patients noted clinical improvement 3 to 6 months after starting therapy and all patients had improvement after 12 months of therapy. An RCT randomized 20 atopic dermatitis patients to omalizumab or placebo for 16 weeks. Although some laboratory markers, such as free IgE, surface IgE, and FceRI expression were reduced, no significant improvement was noted in AD symptoms. Results were similar in another study of patients with severe AD. A meta-analysis reported no concrete evidence that omalizumab was effective in treating AD, although 43% of patients improved clinically with omalizumab. There may be some patients who are more responsive than others.

Xolair for Food Allergies

Evidence to support using omalizumab for food allergies is considered fair with two early phase trials reporting some success, with some trial participants tolerating more than 8 peanuts at the end of therapy (up from ½ a peanut) but 25% reporting no improvement in therapy. One difficulty with conducting food allergen trials is the high risk of anaphylaxis during qualifying food challenges makes it difficult to retain participants. Early studies suggest that omalizumab may be beneficial for food allergies, but the findings are not conclusive.
Recently, the use of oral immunotherapy for food allergies reported benefits in patients with milk, egg, and peanut allergy. Omalizumab may facilitate oral desensitization to peanut and milk and the addition of omalizumab has allowed some children to receive oral immunotherapy to multiple foods simultaneously, including milk, egg, peanut, wheat, soy, and tree nuts.

Xolair for Eosinophilic Gastrointestinal Diseases

There is weak evidence to suggest that omalizumab may be effective for eosinophilic esophagitis. In two case studies of patients with eosinophilic esophagitis and multiple food allergies, the addition of omalizumab to the patient’s standard therapy reduced symptoms of eosinophilic esophagitis but did not improve endoscopic and histologic changes. In a randomized prospective trial in 30 patients who were either refractory to or had relapsed after topical corticosteroids, Xolair for 16 weeks did not improve either esophageal eosinophil counts or symptom scores. In an open-label study, only 5 out of 15 patients with eosinophilic esophagitis had histological and clinical improvement after 3 months of treatment. In nine patients treated with omalizumab every 2 weeks for 16 weeks, symptom scores were decreased by 70% although there was a non-significant decrease in eosinophils present in the duodenum and stomach. No effect on T-cell function was noted. Overall, omalizumab may be effective for select patients with eosinophilic-based GI diseases, especially those with low blood eosinophil counts.

Xolair for Allergic Bronchopulmonary Aspergillosis (ABA)

The evidence is too weak to recommend omalizumab for ABA. Treatment with omalizumab improved lung functions and reduced respiratory symptoms and systemic corticosteroid use in 8 children with allergic bronchopulmonary aspergillosis and cystic fibrosis. A retrospective analysis found omalizumab was steroid-sparing and reduced inflammatory markers and symptom scores, even with elevated IgE levels.

Xolair for Nasal Polyps

The evidence is too weak to recommend omalizumab for nasal polyps. In an RCT of patients with nasal polyps and comorbid asthma 16 were treated with either omalizumab or placebo (8) for 16 weeks. Only the omalizumab-treated patients had a significant improvement in their nasal and asthma symptom scores and nasal polyp size decreased by both endoscopy and CT scan assessment, regardless of allergic status. A similar study of patients with nasal polyps who kept on their regular medication regimen found the addition of omalizumab decreased nasal polyp size but did not significantly affect symptoms compared to the placebo group. A retrospective analysis of eight subjects demonstrated that omalizumab after polypectomy may reduce the severity of nasal polyp recurrence.

Why hasn’t Xolair been approved for other allergies?

It is unknown why Xolair has not been approved for other conditions. Reasons may include:
• The makers of Xolair, Genentech/Novartis have not sought further approval
• The evidence for using Xolair for other allergic conditions ranges from good to weak depending on the condition
• There is a risk of anaphylaxis with the first few doses of Xolair that require patients being administered Xolair to be monitored which may make it cumbersome or risky for widespread use
• Xolair needs to be given by subcutaneous injection regularly which may be difficult for some people
• Xolair costs approximately $1,300 per injection, and there are much cheaper alternatives.