The FDA has approved Impavido (miltefosine) to treat a tropical disease called leishmaniasis. Leishmaniasis is a disease caused by Leishmania, a parasite which is transmitted to humans through sand fly bites. The disease occurs primarily in people who live in the tropics and subtropics. Most U.S. patients acquire leishmaniasis overseas.

Impavido is an oral medicine approved to treat the three main types of leishmaniasis: visceral leishmaniasis (affects internal organs), cutaneous leishmaniasis (affects the skin) and mucosal leishmaniasis (affects the nose and throat). It is intended for patients 12 years of age and older. Impavido is the first FDA-approved drug to treat cutaneous or mucosal leishmaniasis.

The FDA granted Impavido Fast Track Designation, Priority Review and Orphan Product Designation. These designations were granted because the drug demonstrated the potential to fill an unmet medical need in a serious disease or condition, the potential to be a significant improvement in safety or effectiveness in the treatment of a serious disease or condition and is intended to treat a rare disease, respectively. With this approval, Impavido’s manufacturer, Paladin Therapeutics, is awarded a Tropical Disease Priority Review Voucher under a provision included in the FDA Amendments Act of 2007 that aims to encourage development of new drugs and biological products for the prevention and treatment of certain tropical diseases.

Impavido’s safety and efficacy were evaluated in four clinical trials. A total of 547 patients received Impavido and 183 patients received either a comparator drug or a placebo. Results from these trials demonstrated that Impavido is safe and effective in treating visceral, cutaneous and mucosal leishmaniasis.

The labeling for Impavido includes a boxed warning to alert patients and health care professionals that the drug can cause fetal harm and therefore should not be given to pregnant women. Health care professionals should advise women to use effective contraception during and for five months after Impavido therapy.

The most common side effects identified in clinical trials were nausea, vomiting, diarrhea, headache, decreased appetite, dizziness, abdominal pain, itching, drowsiness and elevated levels of liver enzymes (transaminases) and creatinine.