Table 1. Main characteristics of the studies.
| Study | Study Type | Number of participants | Infection Type | Inclusion Criteria | Exclusion Criteria | Intervention Arm | Comparator Arm |
|---|---|---|---|---|---|---|---|
| Lucasti (2016) [28] | RCT | 351 | cIAI | Age >18, Clinically suspected or bacteriologically documented cIAI | APACHE score >30, | REL 250 + Imipenem (n = 118) | Placebo + Imipenem (n = 117) |
| CrCl <50 mL/min, | REL 125 + Imipenem (n = 116) | ||||||
| ALT/AST >3 x UNL, | |||||||
| Effective antibiotic therapy against pathogen before study drug | |||||||
| Sims (2017) [29] | RCT | 298 | cUTI | Age >18 years, clinically presumed and/or registered cUTI or acute pyelonephritis, needing intravenous antimicrobial treatment, confirmatory urine culture results within 48h | Uncomplicated UTI, CrCl <5 mL/min, ALT/AST >3 x UNL, complete urinary obstruction, effective antibiotic therapy before study drug initiation | REL 250 + Imipenem (n = 99) | Placebo + Imipenem (n = 100) |
| REL 125 + Imipenem (n = 99) | |||||||
| Motsch (2020) [40] | RCT | 57 | Imipenem resistant bacteria: | Age ≥18 years, diagnosis of HABP/VABP, cUTI, cIAIs secondary to imipenem nonsusceptible, I/R susceptible, and colistin-susceptible bacteria | APACHE >30, CrCl <15 mL/min, cUTI with urinary obstruction, HABP/VABP with complete obstruction | REL 250 + Imipenem (n = 31) | Colistin + Imipenem (n = 16) |
| cIAI | |||||||
| cUTI | |||||||
| HABP/VABP | |||||||
| Titov (2020) [38] | RCT | 531 | HABP/VABP | Age >18, LRT Specimen collected within 48h of screening, meet diagnostic criteria for HABP/VABP | >24h of effective antibacterial therapy within 72h of randomization, LRT showing only Gram-positive cocci, CrCl <15, pneumonia by an obstructive process like lung cancer | REL 250/500 + Imipenem (n = 264) | Piperacillin/Tazobactam 4 g/500 mg (n = 267) |
RCT, randomized controlled trials; APACHE: acute physiology and chronic health evaluation score; cIAI: complicated intra-abdominal infection; CrCl, creatinine clearance; ALT, alanine transaminase; AST, aspartame transaminase; ULN, upper limit of normal; REL, relebactam; cUTI, complicated urinary tract infection; LRT, lower respiratory tract; HABP, hospital-acquired bacterial pneumonia; VABP, ventilator-associated bacterial pneumonia.