The primary objective of this study is to evaluate the efficacy of intravenous ibuprofen on reducing fever at 4 hours.

The primary objective of this study is to evaluate the efficacy of a single 400 mg dose of intravenous ibuprofen on reducing fever greater than or equal to 101.0ºF (38.3ºC), as compared with the efficacy of parallel placebo treatment.

Inclusion Criteria:

1. Be hospitalized
2. Have new (not chronic, within last 7 days) onset of fever, documented by temperature greater than or equal to 101.0ºF (38.3ºC)
3. Have adequate intravenous access
4. Have the ability to understand the requirements of the study, be willing to provide written informed consent (as evidenced by signature on an informed consent document approved by an Institutional Review Board), and agree to abide by the study restrictions and to return for the required assessments

Exclusion Criteria:

1. Be less than 18 years of age
2. Have received antipyretic drug therapy (e.g., aspirin, other NSAIDs, or acetaminophen) within 4 hours before dosing
3. Have any history of allergy or hypersensitivity to any component of IVIb, NSAIDs (including aspirin), or COX-2 inhibitors
4. Be pregnant or nursing
5. Have a history of severe head trauma that required current hospitalization, intracranial surgery, or stroke within the previous 30 days, or any history of intracerebral arteriovenous malformation, cerebral aneurysm, or central nervous system mass lesions
6. Weigh less than 40 kg
7. Have a history of congenital bleeding diatheses (e.g., hemophilia) or any active clinically significant bleeding, or have underlying platelet dysfunction, including (but not limited to) idiopathic thrombocytopenic purpura, disseminated intravascular coagulation, or congenital platelet dysfunction
8. Have gastrointestinal bleeding that has required medical intervention within the previous 6 weeks (unless definitive surgery has been performed)
9. Have a platelet count less than 30,000/mm3
10. Be receiving full dose anticoagulation therapy
11. Have fever secondary to blood or drug reaction
12. Have an expected life span of less than 14 days because of imminent withdrawal of life support or severity of illness
13. Be receiving treatment with corticosteroids (Patients who are expected to receive corticosteroids during the Treatment Period or through Hour 120 of the Post-treatment Period are not eligible.)
14. Have neurogenic fever
15. Be on dialysis, have oliguria or creatinine greater than 3.0 mg/dL, or be receiving nephrotoxic drugs
16. Have had major surgery within the past 12 hours, unless adequate hemostasis has been achieved
17. Have received another investigational drug within the past 30 days
18. Become afebrile (temperature below 101.0ºF [38.3ºC]) before dosing and not redevelop fever entry criteria during this hospitalization
19. Be otherwise unsuitable for the study, in the opinion of the Investigator