This study will evaluate the safety of the Leish-111f + MPL-SE vaccine in adult subjects with a previous exposure to the Leishmania parasite (but without current or past history of leishmaniasis).

Cutaneous leishmaniasis is a disfiguring disease that can progress to mucosal leishmaniasis, a more serious and possibly fatal form of Leishmania disease. All available medical therapies require weeks of treatment and cause significant toxicity. It appears that Leishmania infections can be eliminated or prevented by T helper 1 immune responses. These findings argue that a vaccine that generates a T helper 1 response against the parasite will prevent the infection and disease. This is a phase 1, open-label study to evaluate the safety, tolerability and immunogenicity in Montenegro skin test (MST)-positive healthy adults of an investigational vaccine being developed for the prophylaxis of cutaneous leishmaniasis. The vaccine, identified as Leish-111f + MPL-SE, consists of a recombinant three-antigen Leishmania polyprotein (Leish-111f, 10 μg) together with the adjuvant MPL-SE (25 μg). The vaccine will be given to each study subject three times at 4 week intervals.

Inclusion Criteria:

• Must have positive Montenegro skin test (reaction >5 mm)
• Must be in good general health with normal lab values
• Negative for HIV, hepatitis B and C

Exclusion Criteria:

• History of leishmaniasis or exposure to Leishmania vaccine or MPL-SE.
• Pregnant or nursing female