Tedizolid: new data and experiences for clinical practice

Pharmacotherapies for multidrug-resistant gram-positive infections: current options and beyond

INTRODUCTION

Infections due to multidrug-resistant organisms (MDRO) are a serious concern for public health with high morbidity and mortality. Though many antibiotics have been introduced to manage these infections, there are remaining concerns regarding the optimal management of Gram-positive MDROs.

AREAS COVERED

A literature search on the PubMed/Medline database was conducted. We applied no language and time limits for the search strategy. In this narrative review, we discuss the current options for managing Gram-positive MDROs as well as non-traditional antibacterial agents in development.

EXPERT OPINION

Despite their introduction more than 70 years ago, glycopeptides are still the cornerstone in treating Gram-positive infections: all registrative studies of new antibiotics have glycopeptides as control; these studies are designed as not inferior studies, therefore it is almost impossible to give recommendations other than the use of glycopeptides in the treatment of Gram-positive infections. The best evidence on treatments different from glycopeptides comes from post-hoc analysis and meta-analysis. Non-traditional antibacterial agents are being studied to aid in short and effective antibiotic therapies. The use of non-traditional antibacterial agents is not restricted to replacing traditional antibacterial agents with alternative therapies; instead, they should be used in combination with antibiotic therapies.

Current approach to skin and soft tissue infections. Thinking about continuity of care

Skin and soft tissue infections are a common reason for patients seeking inpatient and outpatient medical care. Surgery is an essential part of managing in many episodes. Careful evaluation of antibiotic therapy could help clinicians in early identification to patients with treatment failure and to consider an alternative approach or a new surgical revision in "focus control". With the arrival of new drugs, there is a need to refine the appropriate drug's decision-making. Drugs with a long half-life (long-acting lipoglycopeptides such as dalbavancin or oritavancin), which allows weekly administration (or even greater), can reduce hospital admission and length of stay with fewer healthcare resources through outpatient management (home hospitalization or day hospitals). New anionic fluoroquinolones (e.g. delafloxacin), highly active in an acidic medium and with the possibility of switch from the intravenous to the oral route, will also make it possible to achieve these new healthcare goals and promote continuity of care. Therefore, management should rely on a collaborative multidisciplinary group with experience in this infectious syndrome.

Staph wars: the antibiotic pipeline strikes back

Antibiotic chemotherapy is widely regarded as one of the most significant medical advancements in history. However, the continued misuse of antibiotics has contributed to the rapid rise of antimicrobial resistance (AMR) globally. Staphylococcus aureus, a major human pathogen, has become synonymous with multidrug resistance and is a leading antimicrobial-resistant pathogen causing significant morbidity and mortality worldwide. This review focuses on (1) the targets of current anti-staphylococcal antibiotics and the specific mechanisms that confirm resistance; (2) an in-depth analysis of recently licensed antibiotics approved for the treatment of S. aureus infections; and (3) an examination of the pre-clinical pipeline of anti-staphylococcal compounds. In addition, we examine the molecular mechanism of action of novel antimicrobials and derivatives of existing classes of antibiotics, collate data on the emergence of resistance to new compounds and provide an overview of key data from clinical trials evaluating anti-staphylococcal compounds. We present several successful cases in the development of alternative forms of existing antibiotics that have activity against multidrug-resistant S. aureus. Pre-clinical antimicrobials show promise, but more focus and funding are required to develop novel classes of compounds that can curtail the spread of and sustainably control antimicrobial-resistant S. aureus infections.

The Struggle to End a Millennia-Long Pandemic: Novel Candidate and Repurposed Drugs for the Treatment of Tuberculosis

This article provides an encompassing review of the current pipeline of putative and developed treatments for tuberculosis, including multidrug-resistant strains. The review has organized each compound according to its site of activity. To provide context, mention of drugs within current recommended treatment regimens is made, thereafter followed by discussion on recently developed and upcoming molecules at established and novel targets. The review is designed to provide a clinically applicable understanding of the compounds that are deemed most currently relevant, including those already under clinical study and those that have shown promising pre-clinical results. An extensive review of the efficacy and safety data for key contemporary drugs already incorporated into treatment regimens, such as bedaquiline, pretomanid, and linezolid, is provided. The three levels of the bacterial cell wall (mycolic acid, arabinogalactan, and peptidoglycan layers) are highlighted and important compounds designed to target each layer are delineated. Amongst others, the highly optimistic and potent anti-mycobacterial activity of agents such as BTZ-043, PBTZ 169, and OPC-167832 are emphasized. The evolving spectrum of oxazolidinones, such as sutezolid, delpazolid, and TBI-223, all aiming to exceed the efficacy achieved with linezolid yet offer a safer alternative to the potential toxicity, are reviewed. New and exciting prospective agents with novel mechanisms of impact against TB, including 3-aminomethyl benzoxaboroles and telacebec, are underscored. We describe new diaryloquinolines in development, striving to build on the immense success of bedaquiline. Finally, we discuss some of these compounds that have shown encouraging additive or synergistic benefit when used in combination, providing some promise for the future in treating this ancient scourge.

In vitro Antimicrobial Activity Comparison of Linezolid, Tedizolid, Sutezolid and Delpazolid Against Slowly Growing Mycobacteria Isolated in Beijing, China

Background

The antimicrobial activities of some new oxazolidinones against slowly growing mycobacteria (SGM) have never been well evaluated.

Methods

We evaluate the in vitro susceptibility of 20 reference strains and 157 clinical isolates, pertaining different SGM species, against four oxazolidinones, ie, delpazolid, sutezolid, tedizolid and linezolid. In addition, the association of linezolid resistance and mutations in 23srRNA, rplC, rplD were also tested.

Results

Sutezolid presented the strongest antimicrobial activity against the clinical isolates of M. intracellulare than the other oxazolidinones, with MIC₅₀ at 2 μg/mL and MIC₉₀ at 4 μg/mL. MICs of sutezolid were usually 4- to 8-fold lower than these of linezolid against M. intracellulare and M. avium. The tested isolates of M. kansasii were susceptible to all of the four oxazolidinones. According to the multiple sequence alignment, novel 23srRNA mutations (A2267C and A2266G) in M. intracellulare and rplD mutations (Thr147Ala) in M. avium were identified in this study which have plausible involvement in rendering resistance against linezolid.

Conclusion

This study showed that sutezolid harbors the strongest inhibitory activity against M. intracellulare, M. avium and M. kansasii in vitro, which provided important insights on the potential clinical application of oxazolidinones for treating SGM infections.