A Study of the Safety and Efficacy of Posaconazole Versus Voriconazole for the Treatment of Invasive Aspergillosis (MK-5592-069)

Inclusion Criteria

• Weight >40 kg (88 lb) and ≤150 kg (330 lb); if between 13 and 14 years of age must weigh >= 50 kg (110 lb)
• Must meet the criteria for proven, probable, or possible IA as per 2008 European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) disease definitions at the time of randomization. Proven IA will include those participants with the demonstration of fungal elements (by cytology, microscopy, or culture) in diseased tissue (sterile sampling). Probable IA includes participants with at least 1 host factor, clinical criteria, as well as mycological criteria including both direct and indirect methods. Possible IA includes participants with at least 1 host factor and clinical criteria but without mycological criteria. A modification to the 2008 EORTC/MSG criteria regarding risk factors has been made to allow for the inclusion of participants with any duration of neutropenia as an acceptable inclusion host factor.
• If with possible IA at time of randomization must be willing or be in process of an ongoing diagnostic work up which is anticipated to result in a mycological diagnosis of proven or probable IA postrandomization.
• Must have a central line (e.g., central venous catheter, peripherally-inserted central catheter, etc.) in place or planned to be in place prior to beginning IV study therapy. If without central catheter access, must be clinically stable and able to receive oral study therapy.
• Acute IA defined as duration of clinical syndrome of <30 days.
• Must be willing to adhere to dosing, study visit schedule, and mandatory procedures as outlined in the protocol. The participant must be willing to continue on study therapy for up to 12 weeks and remain in the study through the 1-month follow-up visit.
• The participant must have the ability to transition to oral study therapy during the course of the study.
• Female participants of child-bearing potential must be using a medically accepted method of birth control before beginning study-drug treatment and agree to continue its use for 30 days after stopping study medication
• Is not taking prohibited antifungal prophylaxis or treatment

Exclusion Criteria

• Chronic (>1 month duration) IA, relapsed/recurrent IA, or refractory IA which has not responded to antifungal therapy.
• Has pulmonary sarcoidosis, aspergilloma, or allergic bronchopulmonary aspergillosis (ABPA).
• Known mixed invasive mold fungal infection including Zygomycetes, and/or a known invasive Aspergillus fungal infection in which either study drug may not be considered active.
• Receipt of any systemic (oral, intravenous, or inhaled) antifungal therapy for this infection episode for 4 or more consecutive days (>= 96 hours) immediately before randomization.
• Developed the current episode of IA infection during receipt of >13 days of antifungal prophylaxis with an agent considered to be a mold-active antifungal agent.
• Receipt of posaconazole or voriconazole as empirical treatment for this infection for 4 days (96 hours) or more within the 15 days immediately before randomization.
• Has condition that, in the opinion of the investigator, may interfere with optimal participation in the study.
• Known hypersensitivity or other serious adverse reaction to any azole antifungal therapy or to any other ingredient of the study medication used.
• Females who are pregnant, intend to become pregnant, or are nursing at the time of randomization.
• Known history of Torsade de Pointes, unstable cardiac arrhythmia or proarrhythmic conditions, or a history of recent myocardial infarction within 90 days of study entry.
• Has significant liver dysfunction
• Hepatic cirrhosis or a Child-Pugh score of C (severe hepatic impairment) at the time of randomization.
• Severe renal insufficiency (estimated creatinine clearance <20 mL/min) or on hemodialysis at the time of randomization or likely to require dialysis during the study.
• Known hereditary problem of galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption.
• Acute symptomatic pancreatitis within 6 months of study entry or a diagnosis of chronic pancreatitis at the time of randomization.
• Active skin lesion consistent with squamous cell carcinoma at the time of randomization, or a current or prior history of malignant melanoma within 5 years of study entry.
• On artificial ventilation or receiving acute Continuous Positive Airway Pressure (CPAP)/Bilevel Positive Airway Pressure (BPAP) at the time of randomization.
• Known or suspected Gilbert's disease at the time of randomization.
• Requires treatment with other medications that cannot be stopped and for which there is a known contraindication to co-administration of one or more of the study drugs.