The primary objective of the study is to evaluate the safety and efficacy of SPRC-AB01 versus placebo for treatment of chronic sinusitis in subjects who have had sinus surgery.

Inclusion Criteria:

• Outpatient subjects who have signed a written informed consent.
• A documented history of chronic sinusitis with clinical signs and symptoms suggestive of inflammation or infection for at least 90 consecutive days.
• A documented history of sinus surgery > 90 days.
• Nasal endoscopic exam documenting purulence (pus) from an open sinus cavity with mucosal swelling/edema.
• Women of childbearing potential must have a negative serum pregnancy test and must use adequate birth control throughout the study.

Exclusion Criteria:

• Pregnant females and females unwilling to use adequate birth control.
• Use of any investigational drug/device within 30 days of study screening.
• The following medications will require a certain washout period as determined by the protocol: systemic corticosteroids, mast cells and/or leukotriene inhibitors, anti-inflammatories, decongestants, antihistamines, non-steroidal anti-inflammatory (NSAID) or cyclooxygenase (COX)-2 inhibitors, antibiotics or antifungals.
• Presence of other infections which may require use of systemic antibiotics.
• Known allergy or hypersensitivity to aminoglycosides or other study drug formulation components.
• Recent hospitalization for any reason and/or major surgeries within 30 days of study screening.
• Major elective and/or nasal and/or sinus surgical procedures (including sinuplasty) within 90 days before or 90 days after study screening.
• Known history of neurological or muscular disorders.
• Diagnosis of an immunodeficiency disease.
• Previous diagnosis of cystic fibrosis, ciliary dyskinesias, Kartagener syndrome, empty nose syndrome, Wegener granulomatosis, Churg-Strauss syndrome, Samter syndrome, or sarcoidosis.
• Current or known history of tinnitus, vertigo, or significant sensorineural hearing loss.
• Recent history of alcohol or drug abuse.
• Inability to understand the nature, scope, and possible consequences of the study or study procedures, unless cared for by a legally authorized representative.
• Inability to adhere to the study requirements.
• Previous participation in any Naryx Pharma protocol.