Introduction. Biologic therapy used for the treatment of chronic rhinosinusitis with nasal polyps (CRSwNP) effectively reduces symptom severity; however, its efficacy may depend on the histological type of polyps. The aim of this study was to assess the impact of nasal polyp type on the effectiveness of dupilumab in patients with CRSwNP and comorbid asthma. Materials and methods. This cohort observational study included patients in whom previous surgical and pharmacological treatments had proven insufficient. Participants were categorized into three groups based on polyp histology (edematous, eosinophilic, fibrotic) and received dupilumab (300 mg subcutaneously every two weeks) for 52 weeks. Treatment efficacy was assessed at predefined time points using the Nasal Polyp Score (NPS) and the Lund-Mackay scale. Results. Patients with edematous polyps exhibited the most pronounced improvement on the Lund-Mackay scale, with a mean reduction from 20.94 ± 3.36 to 5.44 ± 3.22 by week 52 (p < 0.001). In contrast, eosinophilic and fibrotic polyps showed less pronounced reductions, from 20.87 ± 2.74 to 7.17 ± 4.15 and from 20.86 ± 2.32 to 10.29 ± 3.24, respectively. Similarly, NPS scores decreased from 6.81 ± 0.83 to 2.00 ± 1.15 in edematous polyps, from 6.96 ± 0.93 to 2.65 ± 1.94 in eosinophilic polyps, and from 6.43 ± 0.85 to 2.50 ± 0.94 in fibrotic polyps by week 52. Conclusions. The edematous polyp type is associated with the most pronounced response to biologic therapy, whereas fibrotic polyps demonstrate a less significant reduction in size. © Сивохин ДА, Свистушкин ВМ, Щенникова ЕС, Авраамова СТ, Александров ПС, Демура ТА, Княжеская НП, Камелева АА, 2025