Introduction: Dupilumab has been shown effective for prurigo nodularis (PN). However, precise data about efficacy of dupilumab as off-label use in PN is missing. We aggregated current evidence to assess efficacy of dupilumab in PN and to identify possible response predictors.
Material and methods: Five electronic databases were searched. Our primary outcome was improvement in pruritus measured by numerical rating scale (NRS). We collected data on NRS before (NRSpre) and after (NRSpost) the dupilumab therapy and designed two categorical variables: 'NRS_50' and 'NRS_100' defined as whether one patient reaches 50% and 100% reduction of the NRSpre. Secondary outcomes included: time until patient perceived any improvement (Time_First) and time until patient reported absence of pruritus (Time_Final).
Results: Data on 45 patients from eleven articles were analyzed. The NRSpre was 8.58 ± 1.89 and the NRSpost was 1.78 ± 2.29. Time_First was 10.15 ± 10.56 weeks, while Time_Final was 19.28 ± 13.71 weeks. 22/45 patients (48.88%) presented with complete resolution (NRS_100) and 37/45 patients (82.22%) had itch half dropped (NRS_50). Time_First was significantly longer in subjects that did not reach NRS_100 (13.13 ± 13.77) than in subjects that did (7.34 ± 7.86, p= .05). Time_First was significantly longer in atopic dermatitis (AD) patients (16.08 ± 16.18) than in subjects without AD (7.02 ± 5.69, p=.01). NRS_50 and NRS_100 presented with a significant association (p=.05).
Conclusion: Dupilumab is an effective target-to-treat agent. In comparison with AD, the clinical response to dupilumab initiates later and, two months of therapy are required until significant itch relieves. Complete remission is rarely observed before 4 months of therapy. Notably, AD-related PN patients need longer treatment than non-AD related PN patients to find any relief. Two early signs of improvement are promising predictors of response to dupilumab: The Time_First and NRS_50. What's already known about this topic?Dupilumab has been shown to be an efficacious treatment for prurigo nodularis (PN)However, literature data on this topic are scattered. What does this study add?This work presents the largest cohort of PN patients treated with dupilumab.Our findings demonstrate dupilumab is a novel and effective choiceIn comparison with atopic dermatitis, the clinical response to dupilumab initiates later.Two months of therapy are required until the itch relieves. Complete remission is rarely observed before 4 months of therapy.Atopic dermatitis-related PN patients need more weeks of treatment than non-atopic dermatitis-related PN patients.
Keywords: Biologic; atopic dermatitis; efficacy; itch; meta-analysis; prurigo nodularis.