Ertapenem

證據等級: L5

預測適應症: 2 個

Ertapenem: From Complicated Intra-Abdominal Infections to Bacterial Arthritis

One-Sentence Summary

Ertapenem is a broad-spectrum carbapenem antibiotic used to treat complicated bacterial infections including intra-abdominal, skin and soft tissue, respiratory, and urinary tract infections. The TxGNN model predicts it may be effective for Bacterial Arthritis, with 0 registered clinical trials and 9 publications currently supporting this direction. A second high-scoring prediction — Staphylococcus aureus infection — carries substantially stronger evidence (8 trials, 20 publications) and is summarised under additional findings.

Quick Overview

Item	Content
Original Indication	Complicated intra-abdominal, skin/soft-tissue, respiratory, and urinary tract infections
Predicted New Indication	Bacterial Arthritis
TxGNN Prediction Score	99.72%
Evidence Level	L3
Philippines Market Status	✗ Not Marketed
Number of Registrations	0
Recommended Decision	Proceed with Guardrails

Why is This Prediction Reasonable?

Ertapenem is a 1β-methyl carbapenem that inhibits bacterial cell wall synthesis by binding preferentially to penicillin-binding proteins (PBP-2 and PBP-3), leading to cell lysis and death. Its antimicrobial spectrum covers methicillin-susceptible Staphylococcus aureus (MSSA), Streptococcus spp., Enterobacteriaceae (including ESBL-producing strains), and anaerobes — all recognised causative agents of bacterial (septic) arthritis.

Bacterial arthritis typically results from haematogenous spread of these same organisms into the synovial space. Because ertapenem’s established indications already target these pathogens at other body sites, extension to joint infections follows logically from its pharmacological profile. Its once-daily dosing schedule is a practical advantage for the prolonged outpatient parenteral antibiotic therapy (OPAT) that bacterial arthritis often requires. A retrospective cohort of 306 OPAT patients (PMID 24709258) identified bone and joint infections as one of the most frequent real-world treatment indications for ertapenem, providing strong clinical plausibility.

Detailed mechanism of action data from DrugBank is not available in this Evidence Pack. Based on published information, ertapenem belongs to the carbapenem class of β-lactam antibiotics; its broad-spectrum efficacy against gram-positive and gram-negative pathogens — the same organisms responsible for bacterial arthritis — makes the TxGNN prediction mechanistically sound.

Clinical Trial Evidence

Currently no clinical trials specifically investigating ertapenem for bacterial arthritis are registered.

Literature Evidence

PMID	Year	Type	Journal	Key Findings
24709258	2014	Retrospective Cohort	Antimicrobial Agents and Chemotherapy	Among 306 OPAT patients, bone and joint infections were among the most common ertapenem indications; long-term safety and efficacy confirmed
22233826	2011	Case Report	Journal of Chemotherapy	Successful treatment of Klebsiella pneumoniae septic wrist arthritis with ertapenem plus levofloxacin
31352398	2019	Case Report	BMJ Case Reports	Citrobacter koseri septic arthritis with concomitant osteomyelitis in a diabetic patient successfully treated with ertapenem
37578166	2023	Case Report	Journal of Investigative Medicine High Impact Case Reports	Prevotella bivia septic arthritis in an immunocompetent adult; initial misdiagnosis, joint aspiration key to diagnosis, ertapenem-based treatment
31585203	2020	Case Report	Anaerobe	First reported Clostridium paraputrificum septic arthritis and osteomyelitis; arthroscopic debridement plus antibiotic coverage highlights need for broad anaerobic spectrum
31220276	2019	Observational Cohort	Journal of Antimicrobial Chemotherapy	Off-label subcutaneous ertapenem used as prolonged suppressive therapy for bone and joint infections when surgery is not feasible; safe and effective in 10 patients
39193962	2024	Observational	Clinical Laboratory	Pathogen distribution and antimicrobial resistance patterns in bone and joint infections among children under four; relevant to susceptibility profiling
38924836	2024	In vitro	Diagnostic Microbiology and Infectious Disease	Auranofin restores ertapenem susceptibility in carbapenem-resistant E. coli; potential combination strategy for resistant joint infections

Additional Finding: Staphylococcus Aureus Infection (TxGNN Rank 2, Score 99.28%)

This indication carries substantially stronger evidence and warrants separate attention.

Clinical Trials

Trial Number	Phase	Status	Enrollment	Key Findings
NCT04886284	Phase 2	Recruiting	60	Randomised trial of cefazolin + ertapenem combination for MSSA bacteremia (CERT sub-study); directly tests ertapenem’s role
NCT07148960	Phase 4	Enrolling by Invitation	300	SABEDTIO: early dual IV antibiotic therapy vs. monotherapy for S. aureus bacteremia; primary endpoint is duration of bacteremia
NCT07376889	Phase 4	Not Yet Recruiting	2096	COMBAT-SAB: large RCT testing combination antibiotic therapy vs. single antibiotic for S. aureus bacteremia
NCT00366249	Phase 3	Completed	1061	Tigecycline vs. ertapenem for diabetic foot infections (includes MSSA); co-primary endpoints not met but ertapenem arm demonstrated efficacy
NCT06634940	N/A	Recruiting	1000	International surveillance of antimicrobial resistance in cirrhosis-related infections including S. aureus
NCT06044272	N/A	Completed	10000	Retrospective AMR profiles in healthcare facilities; documents ertapenem susceptibility patterns
NCT03218397	N/A	Completed	500	RAPIDS-GN: rapid susceptibility testing for Gram-negative bacteremia; validates diagnostic stewardship approaches
NCT06174649	N/A	Completed	900	FAST trial: rapid phenotypic AST for Gram-negative bacteremia; evaluates clinical outcome improvement

Literature Evidence (MSSA)

PMID	Year	Type	Journal	Key Findings
31773134	2020	Case Series	Clinical Infectious Diseases	Cefazolin + ertapenem salvage therapy cleared persistent MSSA bacteremia in 11 cases (6 endocarditis); 8 cleared within 24 hours
27572414	2016	Case Series + In vitro/In vivo	Antimicrobial Agents and Chemotherapy	First description of ertapenem + cefazolin synergy; in vitro and murine skin infection model confirmed synergistic activity against MSSA
38946294	2024	Retrospective Cohort	Journal of Antimicrobial Chemotherapy	Carbapenem combination vs. standard of care for persistent MSSA bacteremia; provides comparative outcomes data
40448546	2025	Retrospective Cohort	Journal of Antimicrobial Chemotherapy	Hypoalbuminemia reduces ertapenem efficacy in MSSA bacteremia combination therapy (caution at albumin < 2.5 g/dL)
35493130	2022	In vitro/Translational	Open Forum Infectious Diseases	Ertapenem + cefazolin shows potent activity within staphylococcal biofilms; explains clinical success in endocarditis
34978891	2022	Basic Science	Antimicrobial Agents and Chemotherapy	Ertapenem stimulates IL-1β release from monocytes; immunomodulatory mechanism may partially explain clinical synergy
39777519	2025	In vitro	Journal of Infectious Diseases	Adjunctive carbapenems (ertapenem or meropenem) enhance ceftaroline/vancomycin killing of MRSA
16801442	2006	In vitro + Animal Model	Antimicrobial Agents and Chemotherapy	Linezolid + ertapenem highly synergistic against MRSA in rabbit endocarditis model
15164963	2004	RCT Subgroup	International Journal of Antimicrobial Agents	Ertapenem 1 g daily vs. piperacillin-tazobactam for complicated skin/soft-tissue infections caused by MSSA; comparable clinical cure rates
39230345	2025	Review	AJHP	Comprehensive review of combination treatment options for persistent MSSA bacteremia; positions ertapenem combinations as key strategy

Philippines Market Information

Ertapenem is currently not registered in the Philippines. No regulatory licenses are on file. The drug is marketed globally (e.g., as Invanz by Merck/MSD) and approved in multiple jurisdictions including the US FDA, EMA, and Japan PMDA for complicated intra-abdominal, skin, respiratory, urinary, and pelvic infections. Local registration would be required before any formal clinical use in the Philippines.

Safety Considerations

Please refer to the package insert for safety information.

Key notes from published literature: Patients with hypoalbuminemia (serum albumin < 2.5 g/dL) may experience suboptimal ertapenem exposure due to high protein binding — clinicians should exercise caution when considering combination therapy in this population (PMID 40448546). No drug-drug interaction data was found in the queried database for this Evidence Pack.

Conclusion and Next Steps

Decision: Proceed with Guardrails

Rationale: Multiple published case reports and a retrospective OPAT cohort confirm ertapenem’s real-world use in bacterial/septic arthritis caused by a range of gram-negative and anaerobic organisms, providing reasonable clinical and mechanistic plausibility. No dedicated RCT exists for this specific indication, limiting the evidence to L3. For the related S. aureus infection indication, evidence is considerably stronger, including Phase 2–4 RCTs, creating a credible platform for clinical evaluation.

To proceed, the following is needed:

Philippines FDA registration pathway: Evaluate compassionate use, importation, or full registration options for Ertapenem (Invanz or equivalent)
MOA and safety data: Retrieve full DrugBank record (DB00303) including key warnings, contraindications, and drug interaction profiles; download package insert from EMA/US FDA
Joint PK/PD data: Confirm adequate synovial fluid penetration to support bacterial arthritis indication
Subpopulation safety review: Assess appropriateness in patients with hypoalbuminemia and renal impairment (ertapenem is renally cleared)
Prospective registry or observational study: Real-world data collection on ertapenem use in septic arthritis in the Philippine context
Regulatory gap analysis: Given that ertapenem is already used off-label for bone and joint infections globally, assess whether a formal indication extension or compassionate-use protocol is the more feasible pathway
Disclaimer

This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.