Background and Importance Pharmacovigilance is an important tool for monitoring drug post-marketing safety. Hospital Pharmacist (HP) plays a primary role in the identification of suspected Adverse Drug Reaction (ADRs) due to his direct contact with the patient. In fact, through the application of indirect pharmacovigilance tools in a real-life context, can lead to the identification of hidden or underestimated ADRs.

Aim and Objectives The aim of the study was to evaluate the increase of suspected ADRs reports to biological drugs for the treatment of severe refractory hypereosinophilic asthma (omalizumab, dupilumab, mepolizumab and benralizumab) obtained following the interventions of HP.

Material and Methods A 7-months (October 2022 to May 2023) post-marketing safety study was conducted. The data were collected via a questionnaire consisting of two sections: general data (sex, age, comorbidities, drugs taken and start of therapy) and list reporting the most common side effects where the patient can indicate one or more suspected ADRs among those reported and/or enter any side effect that is potentially linked to the drug. The questionnaire was illustrated and given to the patients at the time of dispensing. The data were also compared with the clinical trials and all adverse reactions reported by patients were entered into the pharmacovigilance network.

Results Initially there were no reports of ADRs for any of the drugs considered. Following the HP’s interventions, 55% (55/100) of patients reported one or more adverse reactions (Mepolizumab 65%, 26/40; dupilumab 54.5%, 12/22; omalizumab 53.3%, 8/15; benralizumab 39.1%, 9/23) bringing the number of reports to 122 (76 mepolizumab; 14 dupilumab; 16 omalizumab; 16 benralizumab). The study also highlighted ADRs not reported in the trials; for mepolizumab were found diffuse petechiae, haemorrhagic period and frequent urination problems with recurrent cystitis (3.5%; 1/26) while for dupilumab was found a higher incidence of herpetic development and alopecia (4.5%; 1/22). A higher percentage of pyrexia was found for benralizumab compared to trials (3%; 12/320 vs 13%; 3/26).

Conclusion and Relevance The data analysis confirmed the importance of the HP role in pharmacovigilance. The investigation in a real-world context characterised by a high heterogenicity of patient characteristics (age, comorbidity, adherence) led to an improvement in the incidence of ADRs reports and to the highlighting of side effects not detected during the clinical trials.

Conflict of Interest No conflict of interest.