Study of the Safety, Tolerability, and Efficacy of MK-7655 + Imipenem/Cilastatin Versus Imipenem/Cilastatin Alone for the Treatment of Complicated Urinary Tract Infection (cUTI) (MK-7655-003 AM4)

The purpose of this study is to determine whether adding 125 mg or 250 mg doses of MK-7655 to imipenem/cilastatin is at least as effective as imipenem/cilastatin alone in adults 18 years or older with complicated urinary tract infection (cUTI).

• Urinary Tract Infections
• Pyelonephritis

• Drug: MK-7655 250 mg with imipenem/cilastatin

  Participants randomized to receive MK-7655 250 mg will be administered a 250 mg dose of MK-7655 IV in a blinded fashion once every 6 hours with each dose infused over a 30-minute interval.

  A 500 mg dose of imipenem/cilastatin will be administered IV in an open-label fashion once every 6 hours with each dose infused over a 30-minute interval.

• Drug: MK-7655 125 mg with imipenem/cilastatin

  Participants randomized to receive MK-7655 125 mg will be administered a 125 mg dose of MK-7655 IV in a blinded-treatment fashion once every 6 hours with each dose infused over a 30-minute interval.

  A 500 mg dose of imipenem/cilastatin will be administered IV in an open-label fashion once every 6 hours with each dose infused over a 30-minute interval.

• Drug: imipenem/cilastatin 500 mg
  A 500 mg dose of imipenem/cilastatin will be administered IV in an open-label fashion once every 6 hours with each dose infused over a 30-minute interval.
• Drug: Placebo to MK-7655
  Participants randomized to receive imipenem/cilastatin alone will receive a placebo-matching infusion of IV normal saline (0.9%) once every 6 hours.

• Experimental: MK-7655 250 mg with imipenem/cilastatin
  MK-7655 250 mg IV with imipenem/cilastatin 500 mg IV every 6 hours
  Interventions:

  • Drug: MK-7655 250 mg with imipenem/cilastatin
  • Drug: imipenem/cilastatin 500 mg
• Experimental: MK-7655 125 mg with imipenem/cilastatin
  MK-7655 125 mg IV with imipenem/cilastatin 500 mg IV every 6 hours
  Interventions:

  • Drug: MK-7655 125 mg with imipenem/cilastatin
  • Drug: imipenem/cilastatin 500 mg
• Placebo Comparator: Placebo to MK-7655 with imipenem/cilastatin
  Matching placebo to MK-7655 (normal saline 0.9%) IV with imipenem/cilastatin 500 mg IV every 6 hours
  Interventions:

  • Drug: imipenem/cilastatin 500 mg
  • Drug: Placebo to MK-7655

Inclusion Criteria:

• At least one of the following risk factors for infection with an antibacterial-resistant organism within the preceding 90 days: Participant has been domiciled in a health care facility (e.g., hospital, nursing home) for at least 48 hours; or participant has an indwelling catheter or has required intermittent urinary catheterization for at least 48 hours; or participant has received at least 3 consecutive days of systemic (oral or IV) antibacterial therapy (excluding antibacterial therapy for the current cUTI infection)
• Clinically suspected and/or bacteriologically documented cUTI or acute pyelonephritis judged by the investigator to be serious (requiring hospitalization and treatment with IV antibiotic therapy)
• Pyuria, determined by a midstream clean-catch (MSCC) or catheterized (indwelling or straight catheter) urine specimen with greater than or equal to 10 white blood cells (WBCs) per high-power field (hpf) on standard examination of urine sediment or greater than or equal to 10 WBCs/mm3 in unspun urine
• One positive urine culture within 48 hours of enrollment

Exclusion Criteria:

• Complete obstruction of any portion of the urinary tract (requiring a permanent indwelling urinary catheter or instrumentation), a known ileal loop, or intractable vesico-ureteral reflux
• A temporary indwelling urinary catheter is in place and cannot be removed at study entry.
• Perinephric or intrarenal abscess or known or suspected prostatitis
• Uncomplicated UTI
• Any history of recent accidental trauma to the pelvis or urinary tract
• Any amount of effective antibiotic therapy after obtaining the urine culture for admission to this study and prior to the administration of the first dose of IV study therapy
• An infection which has been treated with greater than 24 hours of systemic antibiotic therapy known to be effective against the presumed or documented etiologic pathogen(s) within the 72-hour period immediately prior to consideration for entry into the study
• History of serious allergy, hypersensitivity (e.g., anaphylaxis), or any serious reaction to carbapenem antibiotics, any cephalosporins, penicillins, or other beta (β)-lactam agents
• History of serious allergy, hypersensitivity (e.g., anaphylaxis), or any serious reaction to other beta-lactam inhibitors (e.g., tazobactam, sulbactam, clavulanic acid)
• History of a seizure disorder
• Currently being treated with valproic acid or has received treatment with valproic acid in the 2 weeks prior to screening.
• Rapidly progressive or terminal illness unlikely to survive the approximately 6 to 8 week study period
• Pregnant or expecting to conceive, breast feeding, or plans to breast feed within 1 month of completion of the study
• A response to all study therapy (IV study therapy or subsequent oral ciprofloxacin) within the timeframe of treatment specified in this protocol is considered unlikely.
• Concurrent infection that would interfere with evaluation of response to the study antibiotics
• Need for concomitant systemic antimicrobial agents in addition to those designated in the various study treatment groups
• cUTI due to a confirmed fungal pathogen
• Currently receiving immunosuppressive therapy, including use of high-dose corticosteroids
• Prior recipient of a renal transplantation
• Laboratory abnormalities as specified in protocol
• History of any other illness that, in the opinion of the investigator, might confound the results of the study or pose additional risk in administering the study drug
• Currently participating in, or has participated in, any other clinical study involving the administration of investigational or experimental medication (not licensed by regulatory agencies) at the time of presentation or during the previous 30 days prior to screening or is anticipated to participate in such a clinical study during the course of this trial
• Estimated or actual creatinine clearance of <50 mL/minute