Objective: To evaluate the efficacy of recombinant human thrombopoietin (rhTPO) and related factors which influencing the therapeutic effect in adults with severe immune thrombocytopenia (ITP).

Methods: The efficacy of rhTPO in 92 hospitalized adult patients [35 males and 57 females, median age as 34 (18-65) years] with severe ITP, including 7 cases of newly diagnosed ITP, 29 cases of persistent ITP and 56 cases of chronic ITP from May 2012 to May 2014 was retrospectively investigated. All patients received subcutaneous rhTPO, the injected dosage was 300 U·kg⁻¹·d⁻¹ for 14 days, platelet counts were recorded and followed-up for a week.

Results: The overall response rate of rhTPO treatment was 60.9%. The overall response rates in newly diagnosed, persistent and chronic ITP were 71.4%, 62.1% and 58.9% respectively. The median platelet counts on fourth，seventh, fourteenth days of treatment, and the seventh day of withdrawal were 27(5-49), 65(16-138), 133(28-208) and 67(15-134)×10⁹/L, respectively. The median time was 6(5-7) days when platelet counts reached 100×10⁹/L, the median peak time was 11(5-17) days, the median maximum peak of platelet counts was 194(132-274)×10⁹/L in patients who reached CR after treatment. Related factors which affected therapeutic effect were analyzed in patients who reached CR after treatment, and indicated that sex, age, disease stage, express of platelet membrane glycoprotein (GP) and relative number of CD19+ B, CD3+CD4+ T, CD3+CD8+ T lymphocyte in blood samples did not influence the probability of complete response (P>0.05). A few patients with fever, muscle aches, fatigue or dizziness could be self-recovery without special intervention.

Conclusions: Severe ITP in adults treated by rhTPO had satisfactory therapeutic effect and safety.