Inclusion Criteria:  Has provided written informed consent, and has the willingness and ability to comply with all study procedures >= 18 years old Patients with neutropenic fever who have existing malignancy or have undergone hematopoietic stem cell transplantation  Neutropenic fever is defined as the presence of neutropenia defined by:  Absolute neutrophil count (ANC) < 500 cells/mm3 or has an ANC that is expected to decrease to < 500 cells/mm^3 within 48 hours of trial entry and fever defined as:  Single oral temperature measurement of > 101 degree Fahrenheit (F) (38.3 degree Celsius [C]) or a temperature of > 100.4 degree F (38.0 degree C) sustained over a 1- hour period Requires hospitalization for IV empiric antibiotic therapy  If female:  Not breastfeeding Agrees to not attempt to become pregnant during the study. Is surgically sterile or at least 2-years postmenopausal, or if of childbearing potential, has negative screening serum or urine pregnancy test within 5 days If of childbearing potential (including being < 2 years postmenopausal), is willing to practice sexual abstinence or use an effective dual form of contraception with her partner (eg, 2 barrier methods, barrier method plus hormonal method) during treatment and up 28 days post treatment  Exclusion Criteria:  History of any hypersensitivity or allergic reaction to any cephalosporin antibiotic or carbapenem Fever suspected to be caused by a noninfectious cause (eg, fever related to drug or blood product administration) Confirmed fungal infection (eg, Pneumocystis jirovecii etiology in patients with pneumonia) that justifies adding additional empiric antimicrobial therapy (eg, antifungals) Confirmed viral infection that justifies adding additional empiric antiviral therapy (eg, ganciclovir, foscarnet)  Evidence of significant hepatic impairment (any of the following):  Known acute viral hepatitis Alanine aminotransferase (ALT) level > 5 times the upper limit of normal (x upper limit of normal [ULN]). Total bilirubin > 3 x ULN unless isolated hyperbilirubinemia is directly related to the acute infection or due to known Gilbert disease Manifestations of end-stage liver disease, such as ascites or hepatic encephalopathy Known to be human immunodeficiency virus positive Severely impaired renal function, defined as creatinine clearance (CrCl) =< 30 mL/min estimated by the Cockcroft-Gault formula Expected requirement for hemodialysis while on study therapy Received > 24 hours of IV antibacterial therapy (with study drugs) within 72 hours of the initiation of inpatient IV study drug for treatment of suspected infection. Antibiotic prophylaxis and oral antibiotics is allowed. Prophylactic use of antiviral or antifungal medication is permitted Past or current history of epilepsy or seizure disorder; exception: well-documented febrile seizure of childhood Evidence of immediately life-threatening disease, progressively fatal disease, or life expectancy of 3 months or less (eg, moribund or with shock unresponsive to fluid replacement) Unable or unwilling to adhere to the study-specified procedures and restrictions Any condition that would make the patient, in the opinion of the Investigator, unsuitable for the study (eg, would place a patient at risk or compromise the quality of the data Participation in any other ongoing imipenem-relebactam trial