Miltefosine and Benznidazole Combination Improve Anti-Trypanosoma cruzi In Vitro and In Vivo Efficacy.

Drug repurposing and combination therapy have been proposed as cost-effective strategies to improve Chagas disease treatment. Miltefosine (MLT), a synthetic alkylphospholipid initially developed for breast cancer and repositioned for leishmaniasis, is a promising candidate against Trypanosoma cruzi infection. This study evaluates the efficacy of MLT as a monodrug and combined with benznidazole (BZ) in both in vitro and in vivo models of infection with T. cruzi (VD strain, DTU TcVI). MLT exhibited in vitro activity on amastigotes and trypomastigotes with values of IC50 = 0.51 µM (0.48 µM; 0,55 µM) and LC50 = 31.17 µM (29.56 µM; 32.87 µM), respectively. Drug interaction was studied with the fixed-ration method. The sum of the fractional inhibitory concentrations (ΣFICs) resulted in ∑FIC= 0.45 for trypomastigotes and ∑FIC= 0.71 for amastigotes, suggesting in vitro synergistic and additive effects, respectively. No cytotoxic effects on host cells were observed. MLT efficacy was also evaluated in a murine model of acute infection alone or combined with BZ. Treatment was well tolerated with few adverse effects, and all treated animals displayed significantly lower mean peak parasitemia and mortality than infected non-treated controls (p<0.05). The in vivo studies showed that MLT led to a dose-dependent parasitostatic effect as monotherapy which could be improved by combining with BZ, preventing parasitemia rebound after a stringent immunosuppression protocol. These results support MLT activity in clinically relevant stages from T. cruzi, and it is the first report of positive interaction with BZ, providing further support for evaluating combined schemes using MLT and exploring synthetic alkylphospholipids as drug candidates.

Effectiveness of MT regimen in treatment of acute monocytic leukemia and its relationship with karyotype / 白血病·淋巴瘤

Objective To evaluate the effectiveness and side effect of MT regimen (mitoxantrone plus teniposide) in inductive chemotherapy and explore the relationship between the effectiveness and karyotype. Methods 33 patients with acute monocytic leukemia were divided into two groups according to the treatment history or risk status according to cytogenetics MRC criteria. Group A (n=23) and B (n=10) were primary treatment and no remission following one course of DA (daunorubicin plus cytarabine) or HDA (Harringtonine,daunorubicin plus cytarabine) regimen,respectively. According to MRC criteria,group C (n=29) and D (n=4) were intermediate and adverse group. All the cases received two courses MT regimen chemotherapies to induce remission. The results and side effects were analysed. Results The complete remission rate and effective rate in group A and B were 83 % (19/23) and 60 % (6/10),91 % (21/23) and 70 % (7/10) respectively. The complete remission rate and effective rate in group C and D was 83 % (24/29) and 25 % (1/4),88 % (26/29) and 50 % (2/4) respectively. In complex cytogenetic group and 11q23 abnormal without complex cytogenetic group,CR rate was 0 (0/3) and 100 % (4/4). The time point,count of WBC nadir and the duration of WBC were less than 1×109/L is (7±3) day after chemotherapy,(0.4±0.2)×l09/L,(8±5) day. Chemotherapy related mortality was 0. Conclusion MT regimen was highly effective and safe in inducing remission in acute monocytic leukemia,including the cases which achieved no remission following one course of DA or HDA regimen. The effectiveness of MT regimen relates to the cytogenetics. MT regimen may be highly effective in cases with 11q23 abnormal and poor effective in cases with complex cytogenetic.