SPECIFIC ALLERGEN IMMUNOTHERAPY FROM 1911 TO THE PRESENT DAY: PRIORITY TO SAFETY
Since its discovery in 1911 allergen-specific immunotherapy (AIT) has been widely used due to its efficacy and safety against allergic respiratory diseases.
The initial studies conducted on allergen-specific immunotherapy demonstrated its beneficial effect on hay fever and, in time, led to substantial scientific evidence, which has also been demonstrated by some meta-analyses (1).
Above all, on the safety issue, efforts have been made over the years to find an AIT formulation that not only maintained its efficacy, that is, immunogenicity, which is essential for inducing the immunological modification associated with effective AIT, but that also guaranteed the safety of the patient undergoing the treatment (2).
The pharmaceutical form used most frequently is sublingual tablets due to their ease of use. Over time, to satisfy the need to have an increasing number of safe and easy to use products for the patient, sublingual products consisting of allergoids obtained by carbamylation have been introduced.
In fact, carbamylated monomeric allergoids have proven to be effective and safe in patients that suffer from allergic rhinoconjunctivitis caused by dust mites or seasonal allergens, such as graminaceous pollen.
The introduction of allergoids has represented a major step forward for allergen-specific immunotherapy, providing an answer to the problem of systemic reactions to natural extracts with regard both to injection immunotherapy and the sublingual form (3).
In these years of COVID-19 pandemic, pharmacovigilance has certainly shown that close monitoring of the post-vaccination adverse reactions is extremely useful for the medical community and to ensure a continual guarantee of safety for the patient.
With regard to allergen-specific immunotherapy, a pharmacovigilance study conducted on the sublingual tablet pharmaceutical form, which is based on real practice and thus on daily use of the product, outside protected environments, such as clinical trials, presented ADR (adverse drug reactions) rates of 0.0004% and this demonstrates the excellent safety that can be given by an allergoid (4).
ALLERGIC PATIENTS AND THE COVID-19 VACCINE
In these years of the COVID-19 pandemic, people under treatment with medicinal products have had to make many changes to their routine and, in many cases, the approach to their treatment has changed and, in some case, the treatment has been discontinued. Allergic patients under treatment with allergen-specific immunotherapy have also undergone changes to their treatment plan and, in particular, given the critical hospital situation and the near impossibility of reaching outpatient departments, changes to the method of administration of the immunotherapy.
Continuous monitoring of allergic patients and, in particular, allergic patients with asthma has revealed that there is no evidence of an increase in the infection rates in individuals with asthma or worsening of asthma in COVID-19 patients, as observed for the seasonal versions of coronavirus (5).
However, as asthma is associated with hyperreactivity of the airways, the onset of an attack of asthma following an infection could have worsened the patient’s clinical condition. In addition, inadequate control of asthma may lead to a worse response to the triggering factors, so asthma sufferers were advised, right from the start of the COVID-19 pandemic, to continue to take their control drugs, including AIT (6).
As allergic patients benefit from not suspending their treatment and it is difficult to gain access to the outpatient departments, it has been seen that SCIT (subcutaneous immunotherapy) has proven to be the best option for all patients that cannot reach the hospital environment to receive injection treatment and the sublingual treatment with carbamylated monomeric allergoid has provided an easy and safe solution for their management (7).
The introduction of the COVID-19 vaccine has certainly created many doubts and fears in the minds of allergic patients under treatment with allergen-specific immunotherapy and, given the importance of the vaccine in the fight against this public health crisis, it was fundamentally important to comprehend the allergic reactions to the approved COVID-19 mRNA vaccines (8).
Right from the beginning, the Italian scientific societies elaborated guidelines that could be useful in managing allergic patients, reassuring the vaccinating doctors and thus also the patients immediately.
It was reiterated that patients under treatment with specific immunotherapy could continue their treatment without any contraindications (9).
One of the questions that doctors asked themselves was how to continue treatment with specific immunotherapy during the administration of the vaccine and, above all, what kind of immunotherapy should be adopted. Top priority was given to the patient’s safety and the choice of a safe product also in this case, so that the patient could continue specific immunotherapy and also receive the COVID-19 vaccine (10).
Never as during this COVID-19 pandemic have we learned that a safe treatment is fundamentally important to manage patients even in critical situations to make sure that their compliance with the treatment continues (11).
The safety of a treatment must always be considered essential and one of the most important parameters not only in an emergency but also in daily clinical practice.
REFERENCES AND NOTES
- F. A. «Undred years of allergen immunotherapy,» Clin Exp. Allergy, vol. 41, n. 9, pp. 1221-1225, 2011.
- E. C. C. I. C. C. S. M. A. G. G. M. e F. F. , «The role of allergoids in allergen immunotherapy: from injective to sublingual route biblio,» Eur Ann Allergy Clin Immunol, vol. 52, n. 5, pp. 195-204, 2005.
- G. M. O. B. e D. R. , «Monomeric chemically modified allergens: immunologic and physicochemical characterization,» Allergy, vol. 51, n. 1, pp. 8-15, 1996.
- E. C. C. I. S. U. P. S. e F. F. , «The safety of carbamylated monomeric allergoids for sublingual immunotherapy. Data from a pharmacovigilance study,» Immunotherapy, 2020.
- G. R. O. P. A. I. D. S. e G. v. W. R. , «. Linee guida EAACI su immunoterapia: Allergico rinocongiuntivite,» Allergy, vol. 73, n. 4, pp. 765-798, 2018.
- M. J. 2. C. A. 3. J. B. 4. 5. 6. 7. M. A. 3. C. B. 8. I. A. 9. I. A. 1. e. a. Ludger Klimek 1, «Handling of allergen immunotherapy in the COVID-19 pandemic: An ARIA-EAACI statement,» Allergy , vol. 75, n. 7, pp. 1546-1554, 2020.
- M. E.-L. ,. F. R. A. ,. P. O. F. ,. I. G. N. ,. F. F. ,. G. M. E Compalati, «Allergen Immunotherapy in the Era of SARS-CoV-2,» Investig Allergol Clin Immunol, vol. 30, n. 6, pp. 459-461, 2020.
- R. S. ,. C. A. S. J. ,. L. B. R. e. a. Aleena Banerji Paige G Wickner, «mRNA Vaccines to Prevent COVID-19 Disease and Reported Allergic Reactions: Current Evidence and Suggested Approach,» J Allergy Clin Immunol Pract, vol. 9, n. 4, pp. 1423-1437, 2021.
- P. M. D. G. P. M. B. P. G. D. G. C. D. P. B. D. F. M. P. SIAAIC, «LINEE DI INDIRIZZO PER LA GESTIONE DA PARTE DEGLI ALLERGOLOGI DEI PAZIENTI A RISCHIO DI REAZIONI ALLERGICHE AI VACCINI PER COVID-19».
- M. C. B. M. P. P. O. M. M. C.-K. K. C. C. a. C. G. t. S. G. o. A. &. V. Simonetta Masieri, «Allergen Immunotherapy management during vaccinations: An international survey,» World Allergy Organization Journa, 2021.
- F. F. P. P. S. S. C. I. G. W. C. C. H. G Passalacqua, «Adherence to sublingual immunotherapy: the allergists’ viewpoint,» Allergy, vol. 64, n. 12, pp. 1796-1797, 2009.
