FTB combines cefepime (a fourth-generation cephalosporin) with taniborbactam (VNRX-5133), a cyclic boronate β-lactamase inhibitor. This combination restores cefepime's efficacy against multidrug-resistant Gram-negative pathogens .
Cefepime: Inhibits bacterial cell wall synthesis by binding penicillin-binding proteins.
Taniborbactam: Broadly inhibits Class A, B, C, and D β-lactamases, including metallo-β-lactamases (MBLs) like NDM and VIM .
| Parameter | Value/Outcome | Source |
|---|---|---|
| MIC50/90 for Enterobacterales | 0.06/0.25 µg/mL | |
| Inhibition rate (≤8 µg/mL) | 99.5% of 10,543 isolates | |
| Resistance mechanisms | IMP-type enzymes, PBP3 mutations, efflux |
FTB demonstrated potent activity against carbapenem-resistant Enterobacterales and Pseudomonas aeruginosa, including strains resistant to ceftazidime-avibactam and meropenem-vaborbactam .
While FTB is not an antibody, recent advancements in antibody technology provide context for therapeutic innovation:
BsAbs target two antigens, enabling applications in oncology and immunology:
Catumaxomab (anti-EpCAM/CD3) and blinatumomab (anti-CD19/CD3) are FDA-approved BsAbs for cancer therapy .
Over 30 BsAbs are in clinical trials, with formats including tandem scFv and BiTE (bispecific T-cell engager) .
NeuroMab: Generates monoclonal antibodies for neurological targets using dual ELISA and immunohistochemistry screening .
CPTAC Antibody Portal: Provides 946 characterized antibodies for cancer research, validated via ELISA and Western blot .
Data from the TABS Antibody Database (2019) :
| Development Phase | Percentage of mAbs |
|---|---|
| Preclinical | 45% |
| Phase I/II | 30% |
| Phase III | 15% |
| Marketed (FDA-approved) | 10% |
How do I resolve contradictions between computational models predicting FTB antibody fitness?
Use ensemble approaches: Compare predictions from Rosetta (physics-based) and deep learning models (e.g., AntiBERTy, IgLM) for consensus .
Validate discordant predictions experimentally via high-throughput mutagenesis screens (e.g., Koenig et al.’s 4275-mutation dataset) .
Table 2: Model Performance Across Antibody Properties
| Model | Expression (R²) | Thermostability (R²) | Immunogenicity (R²) |
|---|---|---|---|
| Rosetta | 0.41 | 0.58 | 0.32 |
| AntiBERTy | 0.56 | 0.49 | 0.61 |
| IgLM | 0.52 | 0.53 | 0.59 |
What strategies improve FTB antibody specificity in polyclonal environments?
How should I interpret conflicting transfer ratios of FTB antibodies in maternal-infant cohorts?
Why do in vitro neutralizing assays fail to correlate with in vivo efficacy for some FTB antibodies?