A young Caucasian female with severe
bronchial asthma and Alpha1-antitrypsin (AAT) deficiency, MZ phenotype, experienced a quick and severe limitation of her physical capacity, which negatively affected her psychological state and social life, though she was under a strong
antiasthmatic treatment. Given her declining health status and the significant chronic
corticoid administration-related side-effects (including high reduction of muscle mass and bone density), a clinical trial with commercial intravenous AAT was proposed by the patient's doctors, and accepted by the Spanish Ministry of Health, although it this
therapy was not approved for MZ phenotypes yet. This new
therapy quickly stopped lung function decline rate, dramatically reduced the number of hospital admissions of the patient, suppressed the
oral administration of
prednisone, reversed the
corticosteroid-related health adverse effects, significantly improving her quality of life. Thus, although AAT replacement
therapy is not approved nor indicated for the treatment of
bronchial asthma in MZ patients, its favourable effects observed in this isolated case support the hypothesis that
bronchial asthma could be due to pathogenic mechanisms related to a
protease-
antiprotease imbalance, what which could open new perspectives for future research on the field.