The primary objective of the study is to evaluate the safety and efficacy of Amphotericin B suspension versus placebo in the complete resolution of key chronic sinusitis symptoms during 16 weeks of treatment in patients with refractory, postsurgical CS.

Inclusion Criteria:

• Has a diagnosis of refractory, postsurgical chronic sinusitis
• Has a documented history of chronic sinusitis symptoms for more than 12 weeks
• A CT scan showing a certain level of mucosal thickening in at least 1 maxillary sinus
• An endoscopy documenting the presence of inflammation and absence of stage 4 polyps
• Ability to comply with the study requirements including the ability to administer a nasal lavage twice daily for 4 months
• Females of childbearing potential must use adequate birth control methods and not plan to get pregnant during the course of the study.
• Ability to read or speak English

Exclusion Criteria:

• Has a hypersensitivity to Amphotericin B or the compounds of any study medications
• Is an immunosuppressed patient or is receiving disease modifying agents
• Has an acute upper or lower respiratory illness
• Has an acute exacerbation of chronic sinusitis within 1 month prior to randomization
• Has used systemic antibiotic therapy for reasons other than acute sinusitis within 3 weeks prior to randomization
• Has used any antibiotic therapy for acute complication of chronic sinusitis within 1 month prior to randomization
• Has orbital or central nervous system complications
• Has acute asthma at study initiation
• Began using nasal corticosteroids or had a dosage change within 3 months prior to randomization
• Has taken a dose of oral or intravenous steroids to treat any condition other than asthma within 1 month prior to randomization
• Has used any systemic antifungal therapy within 3 months prior to randomization
• Has used intranasal antifungal therapy for chronic sinusitis within 3 months prior to randomization
• Currently has a clinically significant deviated nasal septum that has not been remedied by surgery
• Has an anatomical abnormality which would significantly obstruct the nasal passages
• Has cystic fibrosis
• Is pregnant
• Has stage 4 polyposis
• Has any significant medical condition that in a doctor's opinion could affect the patient's participation in the trial
• Has used any investigational product within 1 month of study initiation
• Has a history of cancer other than treated squamous cell or basal cell carcinoma of the skin that has not been in full remission for at least 5 years prior to study initiation