Observational long-term follow-up study of rapid food oral immunotherapy with omalizumab.

BACKGROUND: A number of clinical studies focused on treating a single food allergy through oral immunotherapy (OIT) with adjunctive omalizumab treatment have been published. We previously demonstrated safety and tolerability of a rapid OIT protocol using omalizumab in a phase 1 study to achieve desensitization to multiple (up to 5) food allergens in parallel, rapidly (7-36 weeks; median = 18 weeks). In the current long-term, observational study, we followed 34 food allergic participants for over 5 years, who had originally undergone the phase 1 rapid OIT protocol. METHODS: After reaching the maintenance dose of 2 g protein for each of their respective food allergens as a part of the phase 1 study, the long-term maintenance dose was reduced for some participants based on a pragmatic team-based decision. Participants were followed up to 62 months through standard oral food challenges (OFCs), skin prick tests, and blood tests. RESULTS: Each participant passed the 2 g OFC to each of their offending food allergens (up to 5 food allergens in total) at the end of the long-term follow-up (LTFU) study. CONCLUSION: Our data demonstrate the feasibility of long-term maintenance dosing of a food allergen without compromising the desensitized status conferred through rapid-OIT. Trial registration Registry: Clinicaltrials.gov. Registration numbers: NCT01510626 (original study), NCT03234764 (LTFU study). Date of registration: November 29, 2011 (original study); July 26, 2017 (LTFU study, retrospectively registered).

Feasibility of sustained response through long-term dosing in food allergy immunotherapy.

BACKGROUND: Clinical trials using oral immunotherapy (OIT) for the treatment of food allergies have shown promising results. We previously demonstrated the feasibility of desensitization for up to 5 food allergens simultaneously through OIT. In this observational study, we report the findings of long-term follow-up (LTFU) of the participants treated through a single site OIT phase 1 trial. METHODS: The participants (n = 46) were followed up to 72 months since the time they reached 2 g maintenance dose per food in the initial phase 1 trial. During the long-term maintenance dosing, participants continued or reduced the initial maintenance dose of food allergen protein to high (median 2 g protein) vs. low (median 300 mg protein). Participant follow-up included clinical monitoring, standardized OFCs, and in some cases, skin prick tests and measurement of allergen-specific IgE and IgG4. RESULTS: Irrespective of the high vs. low long-term maintenance dose during LTFU, all participants were able to ingest 2 g protein of each food allergen protein during OFCs performed at the end of our LTFU. CONCLUSION: Our LTFU cohort of food OIT participants from a single site, phase 1 OIT study, supports the feasibility of sustained desensitization through long-term maintenance dosing. Trial registration Registry: Clinicaltrial.gov. Registration numbers: NCT01490177 (original study); NCT03234764 (LTFU study). Date of registration: November 29, 2011 (original study); July 26, 2017 (LTFU study, registered).