Decline in Clinical Efficacy of Oral Miltefosine in Treatment of Post Kala-azar Dermal Leishmaniasis (PKDL) in India

Background: recent studies have shown significant decline in the final cure rate after miltefosine treatment in visceral leishmaniasis. this study evaluates the efficacy of miltefosine in the treatment of post kala-azar dermal leishmaniasis (pkdl) patients recruited over a period of 5 years with 18 months of follow-up. methodology: in this study 86 confirmed cases of pkdl were treated with two different dosage regimens of miltefosine (regimen i- 50mg twice daily for 90 days and regimen ii- 50 mg thrice for 60 days) and the clinical outcome assessed monthly. cure/relapse was ascertained by clinical and histopathological examination,and measuring parasite burden by quantitative real-time pcr. in vitro susceptibility of parasites towards miltefosine was estimated at both promastigote and amastigote stages. results: seventy three of eighty six patients completed the treatment and achieved clinical cure. approximately 4% (3/73) patients relapsed by the end of 12 months follow-up,while a total of 15% (11/73) relapsed by the end of 18 months. relapse rate was significantly higher in regimen ii (31%) compared to regimen i (10.5%)(p<0.005). parasite load at the pre-treatment stage was significantly higher (p<0.005) in cases that relapsed compared to the cases that remained cured. in vitro susceptibility towards miltefosine of parasites isolated after relapse was significantly lower (>2 fold) in comparison with the pre-treatment isolates (p<0.005). conclusion: relapse rate in pkdl following miltefosine treatment has increased substantially,indicating the need of introducing alternate drugs/ combination therapy with miltefosine. © 2015 ramesh et al.