A retrospective analysis of 122 immune thrombocytopenia patients treated with dapsone: Efficacy, safety and factors associated with treatment response

Autor(es)

Colella, Marina P. ^[1] ; Orsi, Fernanda A. ^{[2, 1]} ; Alves, Elizio C. F. ^{[1, 3]} ; Delmoro, Gabriela de F. ^[4] ; Yamaguti-Hayakawa, Gabriela G. ^[1] ; de Paula, V, Erich ; Annichino-Bizzacchi, Joyce M. ^{[5, 6]}

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Hematol & Hemotherapy Ctr, R Carlos Chagas, 480 Cidade Univ Zeferino Vaz, BR-13083878 Campinas, SP - Brazil

^[2] Univ Estadual Campinas, Sch Med Sci, Dept Clin Pathol, Campinas, SP - Brazil

^[3] Hosp Geral Santa Marcelina, Sao Paulo, SP - Brazil

^[4] Univ Estadual Campinas, Fac Med Sci, Campinas, SP - Brazil

^[5] de Paula, Erich, V, Univ Estadual Campinas, Hematol & Hemotherapy Ctr, R Carlos Chagas, 480 Cidade Univ Zeferino Vaz, BR-13083878 Campinas, SP - Brazil

^[6] de Paula, Erich, V, Univ Estadual Campinas, Fac Med Sci, Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Thrombosis and Haemostasis; v. 19, n. 9 AUG 2021.
• Citações Web of Science: 0

Resumo

Background The optimum second-line treatment or best sequence of treatments for immune thrombocytopenia (ITP) are yet to be determined. Our institution has accumulated extensive experience regarding the use of dapsone as second-line therapy for ITP. Objectives We aimed to assess the efficacy rate and safety of dapsone treatment in ITP patients. Patients/Methods Here we report our experience in a retrospective study, including 122 patients, with a median treatment duration with dapsone of 6 months and a median follow-up period of 3.4 years. Results The overall response rate in this cohort was 66%, including 24% of complete responses. Among responders, in 24% a relapse occurred while on treatment. Therefore, a sustained response was observed in 51% of patients. Interestingly, 81% of the responders maintained the response after the interruption of treatment, for a median time of 26 months. Side effects were reported in 16% of the patients in this cohort and treatment was interrupted due to side effects in 11% of patients. The main cause in these cases was hemolytic anemia and methemoglobinemia. Reductions in hemoglobin levels during the use of dapsone were seen in 94% of the patients. Responders presented significantly greater reductions in their hemoglobin levels than nonresponders did: median hemoglobin drop of 1.9 g/dl vs. 1.2 g/dl (p = .004). Conclusions Our findings suggest that dapsone has adequate efficacy and is well tolerated. Although the mechanism of action is still unclear, our observation that the degree in the drop of hemoglobin is greater in responders suggest a possible role of the blockage of the reticuloendothelial system in the therapeutic effect of the drug. (AU)

• Processo FAPESP: 16/14172-6 - Investigação de aspectos fisiopatológicos e novas abordagens terapêuticas em doenças tromboembólicas
• Beneficiário: Joyce Maria Annichino-Bizzacchi
• Modalidade de apoio: Auxílio à Pesquisa - Temático