Secnidazole (trade names Flagentyl, Sindose, Solosec) is a nitroimidazole derivative used to in the treatment of amoebiasis and bacterial vaginosis. Secnidazole and other 5-nitroimidazole drugs enter micro-organisms by passive diffusion and undergo activation by reduction of the 5-nitro group. In anaerobic micro-organisms, such as Trichomonas, Giardia and Entamoeba spp., this intracellular reduction occurs via the pyruvate ferredoxin oxidoreductase complex and results in a concentration gradient across the cell membrane which, in tum, enhances transport of the parent drug into the cell. Because the electron affinity of the 5-nitroimidazoles is greater than that of reduced ferredoxin, the drug interrupts the normal electron flow. Aerobic micro-organisms have a more positive redox potential (i.e. are more efficient electron acceptors) than secnidazole and other 5-nitroimidazoles, which explains the selective toxicity of these drugs against anaerobic microorganisms. DNA is the intracellular target of the Secnidazole and other 5-nitroimidazoles. Secnidazole and other 5-nitroimidazoles possess selective activity against many anaerobic Gram-positive and Gram-negative bacteria and protozoa. In general, secnidazole and metronidazole were approximately equipotent in activity against Bacteroides fragilis, Trichomonas vaginalis, and Entamoeba histolytica, in in vitro studies. Secnidazole is rapidly and completely absorbed after oral administration. Plasma drug concentrations are linear over the therapeutic dose range of 0.5 to 2g. The tolerability profile of secnidazole does not differ markedly from other 5-nitroimidazoles. The most commonly reported adverse events in clinical trials involved the gastrointestinal tract (nausea, vomiting, glossitis, anorexia, epigastric pain and a metallic taste) and occurred in 2 to 10% of patients. A headache and dizziness were experienced by about 2% of patients. The drug was equally well tolerated in adults and children, and no adverse event required therapeutic intervention or treatment withdrawal.

Velpatasvir (VEL; GS-5816) is an inhibitor of HCV NS5A protein, it demonstrated favourable in vitro and in vivo properties, including potent antiviral activity against hepatitis C virus genotypes 1 to 6 replicon, good metabolic stability, low systemic clearance, and adequate bioavailability and physicochemical properties to warrant clinical evaluation. Velpatasvir is used together with sofosbuvir in the treatment of hepatitis C infection of all six major genotypes. A once-daily, single-tablet, pangenotypic regimen comprising the HCV NS5B polymerase inhibitor sofosbuvir and the HCV NS5A inhibitor velpatasvir (sofosbuvir/ velpatasvir; Epclusa) has recently been approved for the treatment of adults with chronic HCV genotype 1, 2, 3, 4, 5 or 6 infection in the USA, EU and Canada.

Elbasvir is an inhibitor of the Hepatitis C Virus (HCV) Non-Structural protein 5A (NS5A). Elbasvir was approved by the FDA in January 2016 for the treatment of hepatitis C. It was developed by Merck and completed Phase III trials, used in combination with the NS3/4A protease inhibitor grazoprevir under the trade name Zepatier. Zepatier is indicated for treatment of chronic HCV genotype 1 or 4 infection in adults.

Isavuconazole is an active form of isavuconazonium, a prodrug which is marketed under the name Cresemba. Isavuconazole inhibits lanosterol 14-alpha demethylase (or CYP51A1) and leads to the accumulation of ergosterol toxic precursors in the fungal cytoplasm. Isavuconazole is indicated for the treatment of invasive aspergillosis and invasive mucormycosis.

Tedizolid phosphate is an oxazolidinone prodrug which in the body is dephosphorylated to the active compound tedizolid. The antibacterial activity of tedizolid is mediated by binding to the 50S subunit of the bacterial ribosome resulting in inhibition of protein synthesis. Tedizolid inhibits bacterial protein synthesis through a mechanism of action different from that of other non-oxazolidinone class antibacterial drugs; therefore, cross-resistance between tedizolid and other classes of antibacterial drugs is unlikely. Tedizolid is bacteriostatic against Gram Positive bacteria such as enterococci, staphylococci, and streptococci. No drug-drug interactions were identified with tedizolid.

Ledipasvir is an inhibitor of the Hepatitis C Virus (HCV) NS5A protein required for viral RNA replication and assembly of HCV virions. Approved in October 2014 by the FDA, ledipasvir and sofosbuvir (tradename Harvoni) are direct-acting antiviral agents indicated for the treatment of HCV genotype 1 with or without cirrhosis.

Ceftolozane is a novel a cephalosporin-class antibacterial drug. In combination with a beta-lactamase inhibitor tazobactam (ZERBAXA, ceftolozane/tazobactam ) ceftolozane, is currently indicated for the treatment of the adult patients with complicated intra-abdominal infections caused by designated Gram-negative and Gram-positive microorganisms and complicated urinary tract infections caused by certain Gram-negative bacteria, including those caused by multi-drug resistant Pseudomonas aeruginosa. To reduce the development of drug-resistant bacteria and maintain the effectiveness of ZERBAXA and other antibacterial drugs, ZERBAXA should be used only to treat infections that are proven or strongly suspected to be caused by susceptible bacteria. Safety and effectiveness in pediatric patients have not been established.

Oritavancin is an glycopeptide antibiotic with bactericidal activity effective in treating infections caused by Gram-positive organisms. It treats complicated skin and skin structure infections. This drug demonstrates similar activity to vancomycin, but it has stronger activity against Staphylococcus and Enterococcus. The pharmacokinetics and pharmacodynamics of oritavancin appear to be favourable and once-daily dosing is likely. The incidence of multi-drug resistant bacteria is increasing and explorations into additional treatment options are essential. Oritavancin is marketed under the brand name Orbactiv. Orbactiv is indicated for the treatment of adult patients with acute bacterial skin and skin structure infections caused or suspected to be caused by susceptible isolates of designated Gram-positive microorganisms. Oritavancin has the following mechanism of action: 1) Inhibition of the transglycosylation (polymerisation) step of cell wall biosynthesis by binding to the stem peptide of peptidoglycan precursors 2) Inhibition of the transpeptidation (crosslinking) step of cell wall biosynthesis by binding to the peptide bridging segments of the cell wall 3) Disruption of bacterial membrane integrity, leading to depolarisation, increased permeability and rapid cell death.

Sofosbuvir is a nucleotide analog inhibitor of hepatitis C virus NS5B polymerase - the key enzyme mediating HCV RNA replication. Sofosbuvir is a prodrug and after ingestion it is rapidly converted to GS-331007, the predominant circulating drug that accounts for greater than 90% of the systemically active drug. The compound GS-331007 is efficiently taken up by hepatocytes, whereby cellular kinases convert GS-331007 to its pharmacologically active uridine analog 5’-triphosphate form (GS-461203). This triphosphate compound mimics the natural cellular uridine nucleotide and is incorporated by the HCV RNA polymerase into the elongating RNA primer strand, resulting in chain termination. The active form GS-461203 targets the NS5B catalytic site and acts as a non-obligate chain terminator. The active compound (GS-461203) does not inhibit host DNA polymerases, RNA polymerases, or mitochondrial RNA polymerase. Sofosbuvir (alone or in in combination with other medications) is used to treat Hepatitis C.

Dolutegravir is an integrase inhibitor that is meant to be used as part of combination therapy for the treatment of HIV. Dolutegravir inhibits HIV integrase by binding to the integrase active site and blocking the strand transfer step of retroviral deoxyribonucleic acid (DNA) integration which is essential for the HIV replication cycle. Dolutegravir coadministered with dofetilide can result in potentially life-threatening adverse events.