[A Multi-center Clinical Trial of Recombinant Human Thrombopoietin in the Treatment of Chemotherapy-induced Thrombocytopenia in Patients with Solid Tumor]

Objective: To assess the efficacy and safety of recombinant human thrombopoietin (rhTPO) on chemotherapy-induced thrombocytopenia in patients with solid tumor.

Methods: In this randomized crossover self-controlled multi-center clinical trial, 154 patients with solid tumor were randomly divided into two groups (group A 77 cases and group B 77 cases). All patients were given the same two cycles of chemotherapy. In group A, the first cycle was treated cycle, in which patients were given rhTPO, while the second cycle was non-treated cycle as a control. In group B, the first cycle was non-treated cycle as a control, while the second cycle was treated cycle. RhTPO 1.0 microg/(kg x d) was administered subcutaneously 6-24 hours after chemotherapy for the longest 14 days. Laboratory tests included complete blood counts, urinalysis, serum chemistry, coagulant test, chest radiography, and electrocardiogram. Serum samples were screened for anti-rhTPO antibodies.

Results: In both group A and group B, platelet decrease and duration had no significant difference between the treated cycle and non-treated cycle. Platelet count was higher in the treated cycle, than in the non-treated cycle: [minimal mean platelet count (64.4 +/- 45.4) x 10(9) cells/L and (52.4 +/- 30.9) x 10(9) cells/L (P=0.000), maximal mean platelet count (263.9 +/- 142.5) x 10(9) cells/L and (148.9 +/- 67.7) x 10(9) cells/L (P=0.000)]. Duration of thrombocytopenia was shorter in the treated cycle than in the non-treated cycle [days with platelet count < 50 x 10(9) cells/L, (2.5 +/- 3.9) and (3.7 +/- 5.7) (P=0.04); days with platelet count recovered > or = 75 x 10(9) cells/L, (10.3 +/- 8.7) and (14.0 +/- 8.9) (P=0.000), and days with platelet count recovered > or = 100 x 10(9) cells/L, (15.9 +/- 10.5) and (21.1 +/- 9.5) (P=0.000)]. The need for platelet transfusion was not significantly reduced in treated cycle. The effects of rhTPO on WBC, Hb, hepatic function, renal function, and coagulant function were not found. Transient low-titer non-neutralizing antibody was developed in one patient. Therapy with rhTPO was tolerated by all patients. Mild side effects were observed in individual patients, including fever, dizziness, and chill. Conclusion Administration of rhTPO after chemotherapy can significantly reduce the degree and duration of thrombocytopenia and promote platelet recovery. Therapy with rhTPO seems to be safe.