Invasive aspergillosis is a type of fungal infection typically identified in very sick patients (for example, patients with cancer or who have had a bone marrow or organ transplant). This study will seek to enroll patients (16 years of age or older) with invasive aspergillosis infections (involving organs or deep tissues) who are failing or could not tolerate standard antifungal therapy. Your doctor will make this determination based upon specific study criteria. Patients that fulfill all study criteria will be treated daily with both the investigational drug and another antifungal agent. The choice of the other agent is up to your doctor. This investigational drug is approved for the treatment of invasive aspergillosis by itself. The safety and efficacy of this investigational drug, in combination with other agents is not known.

The duration of treatment is 12 months.

• Drug: MK0991, caspofungin acetate
• Drug: Comparator: amphotericin B
• Drug: Comparator: lipid formulation of amphotericin B and/or azole

• Patients must meet a specific definition of probable or definite invasive aspergillosis and be considered to have failed or be intolerant of standard antifungal therapy.
• The patient must be at least 16 years old and if a woman of childbearing potential, must have a negative serum or urine pregnancy test sensitive to 25 IU hCG prior to enrollment.