Q&A: Sublingual immunotherapy targets house dust mite allergy in adolescents

Adolescents aged 12 to 17 years with allergic rhinitis induced by house dust mites now can take a sublingual immunotherapy tablet approved by the FDA after review of multiple trials in this age group.

The safety profiles for the house dust mite allergen extract tablet (Odactra, ALK) between adolescents and adults were comparable, with local application site reactions comprising most treatment-related adverse events.

Adolescents may also have unique treatment requirements as they balance care with their educational obligations, extracurricular activities, social lives and their own physical, cognitive and emotional development, according to an ALK press release.

Healio spoke with Michael Blaiss, MD, clinical professor of pediatrics, division of allergy/immunology at the Medical College of Georgia at Augusta University, and paid spokesperson for ALK-Abello Inc., to find out more about Odactra and how its approval stands to impact this patient population.

Healio: Could you provide some details about the prevalence of house dust mite allergies?

Michael Blaiss

Blaiss: According to the American College of Allergy, Asthma, and Immunology, allergic rhinitis is the sixth leading cause of chronic illness in the U.S. The CDC reported in 2018, more than 19 million adults and 5 million children in the U.S. were diagnosed and/or reported with allergic rhinitis within a 12-month period. Nearly 50% of patients with allergies are sensitive to house dust mites. Most dust mite allergy develops in childhood and adolescence, and the allergy oftentimes develops in most people by the age of 20. It is estimated that almost 85% of homes in the U.S. have house dust mites present.

Healio: What are the most common treatments for house dust mite allergies, and how does Odactra improve upon them?

Blaiss: The most common treatments are avoidance, such as removing all carpet, covering the mattress in mite-proof encasing and eliminating dust collectors. There are also medications such as intranasal corticosteroids and oral antihistamines. Odactra is a sublingual immunotherapy (SLIT) tablet, which desensitizes the immune system to house dust mite so not only do patients have fewer or no symptoms, but they also have less need for medication over time.

Healio: Could you describe a typical treatment regimen with Odactra?

Blaiss: Patients with symptoms to house dust mite and a positive blood or skin test documenting IgE antibodies to house dust mite could be candidates for Odactra. The first dose is administered in a health care provider’s office, and the patient is observed for 30 minutes for any reaction. After the first dose, patients can take the tablet at home.

Importantly, patients and their caregivers would be instructed to watch for adverse events after each daily dose. In case of a severe allergic reaction, patients are prescribed an epinephrine autoinjector.

Healio: Is Odactra designed to treat immediate symptoms of house dust mite allergy?

Blaiss: No, Odactra does not lead to immediate relief of house dust mite allergy symptoms. Odactra is a SLIT tablet, which is a type of allergy immunotherapy (AIT). AIT introduces small amounts of allergens into the body, so a person’s immune system can gradually learn to tolerate them. Therefore, unlike medicines that just treat symptoms, Odactra treats the underlying cause of house dust mite allergy and can significantly reduce or, in some cases, eliminate allergy symptoms.

Healio: Why is this treatment particularly necessary for the adolescent population?

Blaiss: Allergic rhinitis symptoms can be different among adolescents compared with adults and children. In a study I authored of adolescents aged 12 to 17 years with seasonal allergic rhinitis, ocular symptoms were more likely to be rated as bothersome by adolescents compared with adults. Adolescents also more commonly reported sneezing and rhinorrhea as most bothersome, compared with children, and were less likely than adults to report nasal pruritus as the most bothersome symptom.

Adolescents with allergic rhinitis may experience difficulties falling asleep, night waking and snoring, and they generally have poorer sleep. Also, allergic rhinitis in adolescents may have a negative impact on school attendance, performance and academic achievement.

Odactra can be taken at home, after the initial administration visit with a health care provider experienced in diagnosing and treating allergies. This avoids regular visits to a physician’s office for injection and may lead to better adherence with the busy lifestyle of the typical adolescent.

Healio: The FDA based its approval on a phase 3 study and on a post-hoc analysis of two pooled, double-blind, placebo-controlled trials. Are there any findings from these studies you would like to highlight?

Blaiss: These studies demonstrated the high efficacy and safety seen with Odactra in the adolescent population. In the post-hoc analysis study, the average total combined rhinitis score based on adjusted means was significantly improved with Odactra compared with placebo (treatment difference of 1.04; P < .01), corresponding to a relative difference of 22% in favor of active treatment. In the MT-18 study, there were no new safety signals, and less than 1% of the adverse events reported by adolescent subjects were assessed as severe (seven events in the Odactra group and three events in the placebo group).

Healio: What impact will this new therapy have on allergy treatment?

Blaiss: With the approval of Odactra for the adolescent population, patients have access to an immunotherapy treatment at home without needles, as we have had for the adult population. Please note there is a boxed warning on Odactra related to anaphylaxis and the need to have an autoinjector of epinephrine. Please see the full prescribing information for additional important safety information.

References:

• Blaiss MS, et al. Ann Allergy Asthma Immunol. 2018;doi:10.1016/j.anai.2018.03.028.
• Matsuoka T, et al. Ped Allergy Immunol. 2017;doi:10.1111/pai.12747.
• Nolte H, et al. Poster P042. Presented at: ACAAI Annual Scientific Meeting; Nov. 10-14, 2022; Louisville, Ky.
• US FDA approves ALK’s Odactra (house dust mite allergen extract) tablet for sublingual use as immunotherapy for adolescents. https://www.prnewswire.com/news-releases/us-fda-approves-alks-odactra-house-dust-mite-allergen-extract-tablet-for-sublingual-use-as-immunotherapy-for-adolescents-301729972.html?tc=eml_cleartime. Published Jan. 25, 2023. Accessed Jan. 26, 2023.

For more information:

Michael Blaiss, MD, can be reached at michael.blaiss@gmail.com.