BACKGROUND: Patients with severe allergic asthma (SAA) and blood eosinophil count ≥0.3x10 METHODS: A real-world multicentre observational study was realized including patients with SAA-NP treated by anti-IgE, anti-IL5/R or anti-IL4R for 6 months. We analyzed the nasal and respiratory symptoms, the number of asthma attacks and salbutamol use/week, acute sinusitis and severe exacerbation rates, the asthma control score, the lung function parameters, the NP endoscopic score, the sinus imaging, and the blood eosinophil count 6 months before and after treatment. RESULTS: One hundred seven patients with SAA-NP were included: 35 treated by anti-IgE, 38 by anti-IL5/R and 34 by anti-IL4R. All the biologics showed similar effectiveness in improving asthma outcomes (symptoms, exacerbation rate, asthma control, lung function). Despite the amelioration of almost all rhinological parameters and sinus imaging in each group, greater benefits were found in the anti-IL4R group in terms of loss of smell (odds ratio OR 3.64[1.3-11.1], p = 0.017), nasal obstruction (OR12.00[2.00-23.10], p = 0.023), and NP endoscopic score (OR 18.10[4.43-24.50]). CONCLUSION: All three biological classes improved asthma and sino-nasal outcomes in patients with SAA-NP. However, anti-IL4R was superior in improving the smell, nasal obstruction, and NP endoscopic size. Larger comparative studies are needed to confirm our results.