Table 1.

New FDA-approved drugs; detailed review 2017–2021 [24].

Drug	Approval Date	FDA-Approved Application	Mechanism of Action	Antibacterial Activity
cefiderocol	14 November 2019	To treat patients with complicated urinary tract infections who have limited or no alternative treatment options	-Cephalosporin with activity against Gram-negative aerobic bacteria. -Functions as a siderophore and binds to extracellular free ferric iron. -Passive diffusion via porin channels. -Actively transported across the outer cell membrane of bacteria into the periplasmic space using a siderophore iron uptake mechanism. Cefiderocol exerts bactericidal action by inhibiting cell wall biosynthesis through binding to penicillin-binding proteins (PBPs).	Gram-negative: Escherichia coli, Enterobacter cloacae complex, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Acinetobacter baumannii, Citrobacter freundii complex, Citrobacter koseri, Klebsiella aerogenes, Klebsiella oxytoca, Morganella morganii, Proteus vulgaris, Providencia rettgeri, Serratia marcescens, Stenotrophomonas maltophilia.
imipenem, cilastatin, and relebactam	16 July 2019	To treat complicated urinary tract and complicated intra-abdominal infections	-Imipenem is a penem antibacterial drug, cilastatin sodium is a renal dehydropeptidase inhibitor, and relebactam is a beta lactamase inhibitor. -Cilastatin limits the renal metabolism of imipenem and does not have antibacterial activity. The bactericidal activity of imipenem results from the binding to PBP 2 and PBP 1B in Enterobacteriaceae and Pseudomonas aeruginosa and the subsequent inhibition of PBPs. Inhibition of PBPs leads to the disruption of bacterial cell wall synthesis. Imipenem is stable in the presence of some beta lactamases. -Relebactam has no intrinsic antibacterial activity, and it protects imipenem from degradation by certain serine beta lactamases such as Sulhydryl Variable (SHV), Temoneira (TEM), and Cefotaximase-Munich.	Complicated Urinary Tract Infections and Complicated Intra-abdominal Infections. Some important bacters: Citrobacter freundii, Klebsiella aerogenes, Enterobacter cloacae, Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Pseudomonas aeruginosa, Bacteroides caccae, Bacteroides fragilis, Bacteroides ovatus, Bacteroides stercoris, Bacteroides thetaiotaomicron, Bacteroides uniformis, Bacteroides vulgatus, Fusobacterium nucleatum, Parabacteroides distasonis. Enterococcus faecalis, Methicillin-susceptible Staphylococcus aureus, Streptococcus anginosus, Streptococcus constellatus. Citrobacter koseri, Enterobacter asburiae, etc.
lefamulin	19 August 2019	To treat adults with community-acquired bacterial pneumonia	-Systemic pleuromutilin antibacterial. -Inhibits bacterial protein synthesis through interactions (hydrogen bonds, hydrophobic interactions, and van der Waals forces) with the A- and P-sites of the peptidyl transferase center (PTC) in domain V of the 23s rRNA of the 50S subunit. The binding pocket of the bacterial ribosome closes around the mutilin core for an induced fit that prevents the correct positioning of tRNA.	S. pneumoniae, H. Influenzae, and M. pneumoniae (including macrolide-resistant strains), and bacteriostatic against S. aureus, and S. pyogenes at clinically relevant concentrations
pretomanid	14 August 2019	For treatment-resistant forms of tuberculosis that affect the lungs	-Nitroimidazooxazine antimycobacterial drug. -inhibiting mycolic acid biosynthesis, thereby blocking cell wall production.	Mutations in five M. tuberculosis genes (ddn, fgd1, fbiA, fbiB, and fbiC) have been associated with pretomanid resistance.
omadacycline	2 October 2018	To treat community-acquired bacterial pneumonia and acute bacterial skin and skin structure infections	-Aminomethylcycline antibacterial (tetracycline class of antibacterial drugs). -The drug binds to the 30S ribosomal subunit and blocks protein synthesis. -Active in vitro against Gram-positive bacteria expressing tetracycline resistance active efflux pumps (tetK and tet L) and ribosomal protection proteins (tet M). In general, omadacycline is considered bacteriostatic; however, omadacycline has demonstrated bactericidal activity against some isolates of S. pneumoniae and H. influenzae.	Gram-positive bacteria that carried ribosomal protection genes (tet M) and efflux genes (tet K and tet L), and in Enterobactericeae that carried the tetB efflux gene. Some S. aureus, S. pneumoniae, and H. influenzae strains carrying macrolide resistance genes (erm A, B, and/or C), or ciprofloxacin resistance genes (gyrA and parC) and beta-lactamase-positive H. influenzae.
eravacycline	27 August 2018	To treat complicated intra-abdominal infections in patients 18 years of age and older	-Fluorocycline antibacterial (tetracycline class of antibacterial drugs). -This drug disrupts bacterial protein synthesis by binding to the 30S ribosomal subunit, thus preventing the incorporation of amino acid residues into elongating peptide chains.	In general, is bacteriostatic against Gram-positive bacteria (e.g., Staphylococcus aureus and Enterococcus faecalis); however, in vitro bactericidal activity has been demonstrated against certain strains of Escherichia coli and K. pneumoniae.
plazomicin	25 June 2018	To treat adults with complicated urinary tract infections	-Aminoglycoside that acts by binding to the bacterial 30S ribosomal subunit, thereby inhibiting protein synthesis.	Enterobacteriaceae in the presence of certain beta-lactamases, including extended-spectrum beta-lactamases (TEM, SHV, CTX-M, AmpC), serine carbapenemases (KPC-2, KPC-3), and oxacillinase (OXA-48). Bacteria producing metallo-beta-lactamases often co-express 16S rRNA methyltransferase, conferring resistance to plazomicin.
secnidazole	15 September 2017	To treat bacterial vaginosis	-5-nitroimidazole antimicrobial. -5-nitroimidazoles enter the bacterial cell as an inactive prodrug where the nitro group is reduced by bacterial enzymes to radical anions. It is believed that these radical anions interfere with the bacterial DNA synthesis of susceptible isolates.	Bacteroides spp., Gardnerella vaginalis, Prevotella spp., Mobiluncus spp., Megasphaera-like type I/II
meropenem and vaborbactam	29 August 2017	To treat adults with complicated urinary tract infections	-The meropenem is a penem antibacterial drug. -The bactericidal action of meropenem results from the inhibition of cell wall synthesis. Meropenem penetrates the cell wall of most Gram-positive and Gram-negative bacteria to bind PBP targets. Meropenem is stable to hydrolysis by most beta-lactamases, including penicillinases and cephalosporinases produced by Gram-negative and Gram-positive bacteria, with the exception of carbapenem hydrolyzing beta-lactamases. The vaborbactam is a nonsuicidal beta-lactamase inhibitor that protects meropenem from degradation by certain serine beta-lactamases such as Klebsiella pneumoniae carbapenemase (KPC). Vaborbactam does not have any antibacterial activity. Vaborbactam does not decrease the activity of meropenem against meropenem-susceptible organisms.	Gram-negative bacteria: Enterobacter cloacae species complex, Escherichia coli, Klebsiella pneumoniae, Citrobacter freundii, Citrobacter koseri, Enterobacter aerogenes, Klebsiella oxytoca, Morganella morganii, Proteus mirabilis, Providencia spp., Pseudomonas aeruginosa, Serratia marcescens.
delafloxacin	19 June 2017	To treat patients with acute bacterial skin infections	-Fluoroquinolone class of antibacterial drugs and is anionic in nature. -Inhibition of both bacterial topoisomerase IV and DNA gyrase (topoisomerase II) enzymes, which are required for bacterial DNA replication, transcription, repair, and recombination.	Gram-positive bacteria Staphylococcus aureus (including methicillin-resistant and methicillin-sensitive strains), Staphylococcus haemolyticus, Staphylococcus lugdunensis, Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus anginosus Group (including S. anginosus, S. intermedius, and S. constellatus), Enterococcus faecalis, Streptococcus dysgalactiae. Gram-negative bacteria E. coli, K. pneumoniae, Enterobacter cloacae, P. aeruginosa, Enterobacter aerogenes, Haemophilus parainfluenzae, Klebsiella oxytoca, Proteus mirabilis.