General Information

Odactra (House Dust Mite Allergen Extract) contains house dust mite allergen extract from Dermatophagoides farinae and Dermatophagoides pteronyssinus.

Odactra is specifically indicated as immunotherapy for the treatment of house dust mite (HDM)- induced allergic rhinitis, with or without conjunctivitis, confirmed by positive in vitro testing for IgE antibodies to Dermatophagoides farinae or Dermatophagoides pteronyssinus house dust mites, or by positive skin testing to licensed house dust mite allergen extracts. Odactra is approved for use in persons 12 through 65 years of age.

Odactra is supplied as tablets for sublingual administration. 

The recommended dose is one tablet daily. Place the tablet immediately under the tongue where it will dissolve within 10 seconds. Allow it to remain there until completely dissolved. Do not swallow for at least 1 minute. Administer the first dose of Odactra under the supervision of a physician with experience in the diagnosis and treatment of allergic diseases. Observe patients in the office for at least 30 minutes following the initial dose.

Mechanism of Action

The precise mechanisms of action of allergen immunotherapy have not been fully established.

Side Effects

Adverse effects associated with the use of Odactra in adults may include, but are not limited to, the following:

throat irritation/tickle, itching in the mouth, itching in the ear, swelling of the uvula/back of the mouth, swelling of the lips, swelling of the tongue, tongue pain, nausea, throat swelling, stomach pain, tongue ulcer/sore on the tongue, mouth ulcer/sore in the mouth, and food tastes different. 

Adverse effects associated with the use of Odactra in adolescents may include, but are not limited to, the following:

throat irritation/tickle, itching in the mouth, itching in the ear, tongue pain, stomach pain, swelling of the uvula/back of the mouth, swelling of the lips, swelling of the tongue, throat swelling, nausea, tongue ulcer/sore on the tongue, and mouth ulcer/sore in the mouth, and diarrhea.

The Odactra drug label comes with a Black Box Warning for severe allergic reactions. Odactra can cause life-threatening allergic reactions such as anaphylaxis and severe laryngopharyngeal restriction. Do not administer to patients with severe, unstable or uncontrolled asthma. Observe patients in the office for at least 30 minutes following the initial dose. Prescribe auto-injectable epinephrine, instruct and train patients or parents/guardians on its appropriate use, and instruct patients or parents/guardians to seek immediate medical care upon its use. Odactra may not be suitable for patients with certain underlying medical conditions that may reduce their ability to survive a serious allergic reaction. Odactra may not be suitable for patients who may be unresponsive to epinephrine or inhaled bronchodilators, such as those taking beta-blockers.

Clinical Trial Results

The FDA approval of Odactra in adults was based on trials involving approximately 2,500 people. Some participants received Odactra, while others received a placebo pill. Participants reported their symptoms and the need to use symptom-relieving allergy medications. During treatment, participants taking Odactra experienced a 16 to 18 percent reduction in symptoms and the need for additional medications compared to those who received a placebo.

The FDA approval of Odactra in adolescents was based on a post hoc analysis of two pooled, double-blind, placebo-controlled trials conducted in North America and Japan. Adolescents aged 12 to 17 years (N=395) with HDM allergic rhinitis were randomized to up to one year of treatment. The study found that Odactra reduced the average total combined rhinitis score (TCRS), the study's primary endpoint, by 22% compared to placebo (treatment difference of −1.04; P<.01).