Miltefosine had good, but imperfect, efficacy for the treatment of cutaneous leishmaniasis (CL), according to data published in Clinical Infectious Diseases. Data showed that its oral administration and manageable toxicities make miltefosine a viable alternative option, but cost and lack of local availability may limit widespread use.
CL is a neglected tropical disease with an estimated 1 million cases globally each year. To investigate the efficacy and tolerability of miltefosine, 26 patients with CL were treated with the drug at the US National Institutes of Health. The majority of patients (81%) were US-based travelers who acquired infections during travel. A total of 7 species of Leishmania were found in patients: Leishmania brazilienis (n=7), Leishmania panamenis (n=5), Leishmania mexicana (n=1), Leishmania infantum (n=3), Leishmania aethiopica (n=4), Leishmania tropica (n=2), and Leishmania major (n=1).
Of the 26 patients, 10 (40%) had been treated unsuccessfully prior to the study. Based on the US Food and Drug Administration, standard miltefosine treatment is 50 mg 2 times daily for patients between 30-44 kg, or 50 mg 3 times daily for patients 45 kg or more for a total of 28 days. Cure was defined as complete epithelialization of lesions after treatment, which was assessed at 3, 6, and 12 months posttreatment. In total, 20 of 26 (77%) patients met the criteria for cure.
Imiquimod was concurrently given to 9 patients, but the proportion of cures was not significantly different. Cures were also reported in participants receiving lower doses. In the 6 patients where treatment failed, 4 patients relapsed, 1 patient failed to respond to therapy, and 1 patient discontinued early due to adverse effects. Adverse events such as gastrointestinal symptoms, nausea, lack of appetite, and vomiting occurred in 97% of patients (n=24); over 73% of patients required some form of clinical intervention, such as ondansetron for nausea and vomiting. Onset of adverse events usually occurred within 1-2 weeks of treatment initiation.
The study is limited by the small sample size with diverse clinical manifestations. Investigators noted that the potential for resistance has been demonstrated in vitro. However, they believe this analysis suggests a potential role for miltefosine in treating both New World and Old World CL species.
“[Miltefosine] is more easily administered, arguably better tolerated, and with efficacy comparable to other standard therapies,” study authors concluded. Providing access to treatment remains a significant challenge and further studies are required to determine optimal dosing, and range or frequency of adverse events in different populations.
Ware JM, O’Connell EM, Brown T, et al. Efficacy and tolerability of miltefosine in the treatment of cutaneous leishmaniasis. Clin Infect Dis. Published online October 28, 2020. doi: https://doi.org/10.1093/cid/ciaa1238.