Tygacil

Drug Overview

Tygacil (tigecycline; Pfizer) is the first of the glycylcycline class of antimicrobial agents. It targets and binds to the 30S subunit of the bacterial ribosomes. This inhibits protein synthesis due to preventing the incorporation of amino acid residues into the peptide chains. The drug is structurally related to tetracyclines, but has activity against a wider spectrum of Gram-positive, Gram-negative, and anaerobic bacterial strains. Tygacil has exhibited limited resistance in comparison to tetracyclines, and has shown no cross-resistance with other antimicrobial agents due to its high binding affinity with the 30S ribosomal subunit. The drug has demonstrated activity against multidrug-resistant bacterial strains including methicillin-resistant Staphylococcus aureus (MRSA), penicillin-resistant Streptococcus pneumonia, some vancomycin-resistant enterococcus (VRE) species, and extended-spectrum beta-lactamase-producing Enterobacteriaceae. Tygacil is mainly a bacteriostatic agent, but it has demonstrated bactericidal activity against some bacterial strains.

Analyst Outlook

Pfizer’s Tygacil (tigecycline) is the first of the glycylcycline class of antimicrobials. The drug exhibited a wider spectrum of antibacterial activity than its structurally related tetracyclines. In 2009, Tygacil gained its first regulatory approval for the treatment of adult patients with community-acquired pneumonia (CAP) in the US market. However, Tygacil’s clinical uptake in the management of CAP, as well as other types of bacterial infections, has been limited by the drug’s safety concerns. In 2013, the US Food and Drug Administration (FDA) issued a black box warning regarding the increased risk of death with Tygacil in comparison to other antimicrobial agents. Datamonitor Healthcare believes that such safety concerns will continue to hinder the drug’s commercial performance.