Efficacy of Delafloxacin versus Moxifloxacin against Bacterial Respiratory Pathogens in Adults with Community-Acquired Bacterial Pneumonia (CABP): Microbiology Results from the Delafloxacin Phase 3 CABP Trial

Comparison of the in vitro activities of delafloxacin and comparators against Staphylococcus epidermidis clinical strains involved in osteoarticular infections: a CRIOGO multicentre retrospective study

OBJECTIVES

Staphylococcus epidermidis bone and joint infections (BJIs) on material are often difficult to treat. The activity of delafloxacin has not yet been studied on S. epidermidis in this context. The aim of this study was to assess its in vitro activity compared with other fluoroquinolones, against a large collection of S. epidermidis clinical strains.

METHODS

We selected 538 S. epidermidis strains isolated between January 2015 and February 2023 from six French teaching hospitals. One hundred and fifty-two strains were ofloxacin susceptible and 386 were ofloxacin resistant. Identifications were performed by MS and MICs were determined using gradient concentration strips for ofloxacin, levofloxacin, moxifloxacin and delafloxacin.

RESULTS

Ofloxacin-susceptible strains were susceptible to all fluoroquinolones. Resistant strains had higher MICs of all fluoroquinolones. Strains resistant to ofloxacin (89.1%) still showed susceptibility to delafloxacin when using the Staphylococcus aureus 2021 CA-SFM/EUCAST threshold of 0.25 mg/L. In contrast, only 3.9% of the ofloxacin-resistant strains remained susceptible to delafloxacin with the 0.016 mg/L S. aureus breakpoint according to CA-SFM/EUCAST guidelines in 2022. The MIC50 was 0.094 mg/L and the MIC90 was 0.38 mg/L.

CONCLUSIONS

We showed low delafloxacin MICs for ofloxacin-susceptible S. epidermidis strains and a double population for ofloxacin-resistant strains. Despite the absence of breakpoints for S. epidermidis, delafloxacin may be an option for the treatment of complex BJI, including strains with MICs of ≤0.094 mg/L, leading to 64% susceptibility. This study underlines the importance for determining specific S. epidermidis delafloxacin breakpoints for the management of BJI on material.

Antibiotic Strategies for Severe Community-Acquired Pneumonia

Despite advancements in health systems and intensive care unit (ICU) care, along with the introduction of novel antibiotics and microbiologic techniques, mortality rates in severe community-acquired pneumonia (sCAP) patients have not shown significant improvement. Delayed admission to the ICU is a major risk factor for higher mortality. Apart from choosing the appropriate site of care, prompt and appropriate antibiotic therapy significantly affects the prognosis of sCAP. Treatment regimens involving ceftaroline or ceftobiprole are currently considered the best options for managing patients with sCAP. Additionally, several other molecules, such as delafloxacin, lefamulin, and omadacycline, hold promise as therapeutic strategies for sCAP. This review aims to provide a comprehensive summary of the key challenges in managing adults with severe CAP, focusing on essential aspects related to antibiotic treatment and investigating potential strategies to enhance clinical outcomes in sCAP patients.

Risk of Multidrug-Resistant Pathogens in Severe Community-Acquired Pneumonia

Severe community-acquired pneumonia (SCAP) is difficult to treat when caused by difficult-to-treat (DTR) pathogens because of limited treatment options and poorer clinical outcomes. Over time, several predictive scoring systems based on risk factors for infection with multidrug resistant pathogens have been developed. We reviewed the available tools for identifying DTR pathogens as the cause of SCAP, both predictive scoring systems and rapid diagnostic methods, to develop management strategies aimed at early identification of DTR pathogens, reducing broad-spectrum antibiotic use and improving clinical outcomes. The scoring systems reviewed show considerable heterogeneity among them at the level of the region studied, the definition of risk factors, as well as which DTR pathogens are the target pathogens. The models described have shown limited effectiveness in reducing inappropriate antibiotic treatment or improving patient outcomes by themselves. However, predictive models could serve as a first step in identifying DTR pathogen infections as part of a larger detection algorithm. Rapid diagnostic tools, such as multiplex polymerase chain reaction, would be useful for the rapid identification of pneumonia-causing pathogens and their resistance mechanisms. In resource-limited settings, rapid tests should be limited to patients at high risk of developing SCAP due to DTR pathogens. We propose an integrative algorithm based on the different scores, taking into account local epidemiological data, where ideally each center should have an antimicrobial stewardship program.

Updated Review on Clinically-Relevant Properties of Delafloxacin

The extensive use of fluoroquinolones has been consequently accompanied by the emergence of bacterial resistance, which triggers the necessity to discover new compounds. Delafloxacin is a brand-new anionic non-zwitterionic fluoroquinolone with some structural particularities that give it attractive proprieties: high activity under acidic conditions, greater in vitro activity against Gram-positive bacteria-even those showing resistance to currently-used fluoroquinolones-and nearly equivalent affinity for both type-II topoisomerases (i.e., DNA gyrase and topoisomerase IV). During phases II and III clinical trials, delafloxacin showed non-inferiority compared to standard-of-care therapy in the treatment of acute bacterial skin and skin structure infections and community-acquired bacterial pneumonia, which resulted in its approval in 2017 by the Food and Drug Administration for indications. Thanks to its overall good tolerance, its broad-spectrum in vitro activity, and its ease of use, it could represent a promising molecule for the treatment of bacterial infections.

New Antibiotics for Staphylococcus aureus Infection: An Update from the World Association of Infectious Diseases and Immunological Disorders (WAidid) and the Italian Society of Anti-Infective Therapy (SITA)

Staphylococcus aureus is an extremely virulent pathogen that is capable of quickly evolving and developing antibiotic resistance. To overcome this problem, new antibiotics have been developed. Some of these have been licenced for use in clinical practice, mainly for the treatment of adults with acute skin and soft tissue infections, in addition to both community-acquired pneumonia (CAP) and nosocomial pneumonia (hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia). In this paper, the main characteristics and clinical use of new licenced anti-staphylococcal drugs have been discussed. In vitro studies have demonstrated that some new anti-staphylococcal antibiotics have better antimicrobial activity and, at least in certain cases, more favourable pharmacokinetic properties and higher safety and tolerability than the presently available anti-staphylococcal drugs. This suggests that they may have a potential use in reducing the risk of failure of S. aureus therapy. However, an in-depth analysis of microbiological and clinical studies carried out with these new drugs seems to indicate that further studies need to be conducted before the problem of resistance of S. aureus to the antibiotics available today can be completely solved. Considering the overall available research, the drugs that are active against S. aureus appear to present a great therapeutic opportunity for overcoming resistance to traditional therapy. There are advantages in the pharmacokinetic characteristics of some of these drugs and they have the potential to reduce hospital stays and economic costs associated with their use.

Delafloxacin: A Review in Community-Acquired Pneumonia

Delafloxacin (BAXDELA^® in the USA; Quofenix^® in the EU) is an anionic fluoroquinolone antibacterial that is approved for the treatment of community-acquired pneumonia (CAP) and acute bacterial skin and skin structure infections in adults. Delafloxacin demonstrated in vitro activity against Gram-positive and Gram-negative pathogens, including drug-resistant isolates. In a phase III trial in adults with CAP, delafloxacin was noninferior to moxifloxacin when assessed against FDA- and EMA-defined primary endpoints, with both fluoroquinolones achieving high treatment success rates. A prespecified subgroup analysis suggested that delafloxacin may be more efficacious than moxifloxacin in patients with a history of asthma or chronic obstructive pulmonary disease (COPD). Delafloxacin was generally well tolerated in patients with CAP, with most treatment-emergent adverse events graded as mild or moderate in severity. Fluoroquinolone-associated adverse events of special interest occurred infrequently, with no events of QT prolongation or phototoxicity reported with delafloxacin. Delafloxacin is an effective and generally well-tolerated treatment that increases the number of available treatments for CAP and, although further research is required, may be a useful option for patients with CAP and comorbid asthma or COPD.

A profile of delafloxacin in the treatment of adults with community-acquired bacterial pneumonia

INTRODUCTION

Community-acquired bacterial pneumonia (CABP) is the most common infectious cause of hospital admission in adults, and poses a significant clinical and economic burden. At the same time, antimicrobial resistance is increasing worldwide with only a few new antibiotics developed in recent years. Delafloxacin is an anionic fluoroquinolone available in intravenous and oral formulations and with a broad spectrum of activity targeting Gram-positives, including methicillin-resistant Staphylococcus aureus (MRSA), gram-negative organisms, and atypical and anaerobic organisms. It also has a better adverse event profile compared to other fluoroquinolones.

AREAS COVERED

This article reviews the current epidemiology of CABP, etiologic agents and current resistance rates, current treatment guidelines, characteristics of delafloxacin (chemistry, microbiology, PK/PD), clinical efficacy and safety in pneumonia and other indications, and regulatory affairs.

EXPERT OPINION

Delafloxacin's susceptibility profile against respiratory pathogens, bioequivalent intravenous and oral formulations and favorable safety profile, support its use for the treatment of CABP. It could be useful as empirical treatment in countries with high rates of penicillin-resistant S. pneumoniae and in patients with suspected or documented pneumonia due to MRSA. In post-influenza staphylococcal bacterial pneumonia, MRSA could be also considered an important pathogen.

Multi-drug resistant gram-negative bacterial pneumonia: etiology, risk factors, and drug resistance patterns

Bacterial pneumonia is one of the most serious public health issues owing to its medical and economic costs, which result in increased morbidity and mortality in people of all ages around the world. Furthermore, antimicrobial resistance has risen over time, and the advent of multi-drug resistance in GNB complicates therapy and has a detrimental impact on patient outcomes. The current review aimed to summarize bacterial pneumonia with an emphasis on gram-negative etiology, pathogenesis, risk factors, resistance mechanisms, treatment updates, and vaccine concerns to tackle the problem before it causes a serious consequence. In conclusion, the global prevalence of GNB in CAP was reported 49.7% to 83.1%, whereas in VAP patients ranged between 76.13% to 95.3%. The most commonly reported MDR-GNB causes of pneumonia were A. baumannii, K. pneumoniae, and P. aeruginosa, with A. baumannii isolated particularly in VAP patients and the elderly. In most studies, ampicillin, tetracyclines, amoxicillin-clavulanic acid, cephalosporins, and carbapenems were shown to be highly resistant. Prior MDR-GNB infection, older age, previous use of broad-spectrum antibiotics, high frequency of local antibiotic resistance, prolonged hospital stays, ICU admission, mechanical ventilation, and immunosuppression are associated with the MDR-GNB colonization. S. maltophilia was reported as a severe cause of HAP/VAP in patients with mechanically ventilated and having hematologic malignancy due to its ability of biofilm formation, site adhesion in respiratory devices, and its intrinsic and acquired drug resistance mechanisms. Effective combination therapies targeting PDR strains and drug-resistant genes, antibiofilm agents, gene-based vaccinations, and pathogen-specific lymphocytes should be developed in the future.

In vitro activity of delafloxacin against highly levofloxacin-resistant invasive isolates of Streptococcus pneumoniae

INTRODUCTION

We report the activity of delafloxacin, a new fluoroquinolone with high affinity for both topoisomerase IV and DNA gyrase, against highly-levofloxacin-resistant invasive strains of Streptococcus pneumoniae.

METHODS

A total of 173 highly-levofloxacin-resistant (MIC>32mg/L) S. pneumoniae invasive isolates were studied. The strains were isolated from blood (n=162) and other sterile fluids (n=11). Serotyping was performed by the Pneumotest-Latex and Quellung reaction. Delafloxacin, levofloxacin, penicillin, cefotaxime, erythromycin and vancomycin MICs were determined by the gradient diffusion method following EUCAST guidelines and breakpoints.

RESULTS

Among the isolates, 32.9% were penicillin non-susceptible, 19.7% cefotaxime non-susceptible, and 76.9% erythromycin resistant. All were susceptible to vancomycin. Delafloxacin MIC₅₀ and MIC₉₀ (mg/L) values were 0.064 and 0.12, respectively; 60% (15/25) of serotype 9V isolates showed delafloxacin MICs≥0.12mg/L.

CONCLUSIONS

Delafloxacin was very active against highly-levofloxacin-resistant invasive isolates of S. pneumoniae. Isolates belonging to serotype 9V showed higher delafloxacin MIC values.

Early Clinical Experience with Delafloxacin: A Case Series

BACKGROUND

-The most recently approved fluoroquinolone for use in the US and Europe, delafloxacin (DLX) provides broad-spectrum coverage, improved side effect profile, and excellent potency. Currently approved for the treatment of acute bacterial skin infections and community-acquired pneumonia, DLX may be useful in the treatment of other infections given the longstanding versatility of other fluoroquinolones.

METHODS

-This is a retrospective review of adult patients treated with DLX at The University of Texas Medical Branch, Galveston, TX from January 1, 2018 to February 1, 2020 using pre-existing electronic medical records. Simple statistics were calculated using Microsoft Excel.

RESULTS

-Five patients were prescribed DLX (median age 59 years, 40% female, 100% outpatient) with a median treatment duration of seven days.  Prescriptions were initiated by infectious diseases specialists (2/5, 40%), emergency medicine physicians (2/5, 40%), and ophthalmologists (1/5, 20%).  The most common conditions treated were prosthetic joint infections (PJI) and acute skin and soft tissue infections (each n = 2).  Both PJIs were caused by multi-drug-resistant Staphylococcus epidermidis. Off-label utilization was high (3/5, 60%). No patient experienced any documented treatment failure due to delafloxacin and there were zero reported adverse events.

CONCLUSIONS

-A new antibiotic with valuable characteristics, DLX treatment was highly successful in this case series, including with multiple off-label indications.  Real-world clinical data with delafloxacin are currently scant.  Prospective data would be useful for identifying future clinical niches for this new fluoroquinolone.

Etiology and efficacy of anti-microbial treatment for community-acquired pneumonia in adults requiring hospital admission in Ukraine

BACKGROUND AND AIM

Empiric therapy of community-acquired pneumonia (CAP) remains the standard care and guidelines are mostly based on published data from the United States or Europe. In this study, we determined the bacterial etiology of CAP and evaluated the clinical outcomes under antimicrobial treatment of CAP in Ukraine.

METHODS

A total of 98 adult subjects with CAP and PORT risk II-IV were recruited for the study. The sputum diagnostic samples were obtained from all patients for causative pathogen identification. Subjects were randomly assigned in a 1:1 ratio to receive delafloxacin 300 mg (n=51) or moxifloxacin 400 mg (n=47) with blinding placebo. The switch to oral treatment was after a minimum of 6 IV doses according to clinical criteria. The total duration of antibacterial treatment was 5-10 days. In vitro susceptibility of pathogens to delafloxacin and other comparator antibiotics was determined.

RESULTS

The most frequently isolated pathogens in adults with CAP were S. pneumoniae - 19.5%, M. pneumoniae - 15.3%, H. influenzae - 13.2%, S. aureus - 10.5%, K. pneumoniae - 10.1%, and H. parainfluenzae - 6.4%. All isolates of S. pneumoniae, S. aureus, M. pneumoniae had sufficient susceptibility to appropriate antibiotics. 9.0% of H. influenzae strains were susceptible to azithromycin. 94.8 % of patients had a successful clinical response to delafloxacin at the end of treatment and 93.9 % - at test-of-cure.

CONCLUSIONS

In Ukraine, the major bacterial agents that induced CAP in adults were S. pneumoniae, M. pneumoniae, H. influenzae, S. aureus, K. pneumoniae, H. parainfluenzae, E. cloacae, L. pneumophila. Delafloxacin is a promising effective antibiotic for monotherapy for CAP in adults and could be used in cases of antimicrobial-resistant strains.

Delafloxacin for the treatment of adult patients with community-acquired bacterial pneumonia

INTRODUCTION

Delafloxacin is a novel fluoroquinolone with peculiar characteristics such as a weak acid character, frequent in vitro activity against methicillin-resistant Staphylococcus aureus (MRSA), and a low potential for resistance selection compared with other fluoroquinolones.

AREAS COVERED

The present narrative review summarizes the available data on the use of delafloxacin for the treatment of community-acquired bacterial pneumonia (CABP).

EXPERT OPINION

Delafloxacin is a novel fluoroquinolone with a unique profile and some interesting characteristics for the treatment of CABP, such as its marked activity against gram-positive bacteria, including MRSA, the possible use as monotherapy (owing to anti-Gram-negative and anti-atypical bacteria activity), the retained activity against many Gram-positive organisms resistant to other fluoroquinolones, and the availability of both oral and intravenous formulations. The results of the DEFINE-CABP phase-3 randomized controlled trial have shown noninferiority of delafloxacin vs. moxifloxacin for the treatment of CABP, thereby providing a further option for this indication. Against this background, future post-marketing experiences remain of crucial importance for further refining the place in therapy of delafloxacin in the real-life management algorithms of CABP, either as first-line option or step-down/outpatient treatment.

Tuberculous shadow in Klebsiella oxytoca pneumonia: An unexpected denouement

Urgent response is required in suspected pulmonary tuberculosis (PTB) cases for infection control, and chest image is the first step to suspect PTB. This case shows an unexpected exception and importance of molecular testing for definite diagnosis.

Eco-Friendly UPLC-MS/MS Quantitation of Delafloxacin in Plasma and Its Application in a Pharmacokinetic Study in Rats

A novel UPLC-MS/MS assay was developed for rapid quantification of delafloxacin (a novel fluoroquinolone antibiotic in plasma samples by one step sample cleanup procedure. Delafloxacin (DFX) and internal standard (losartan) were separated on a UPLC BEH C18 column (50 × 2.1 mm; 1.7 μm) by using gradient programing of a mobile phase containing 0.1% formic acid in acetonitrile and 0.1% formic acid in water. The quantification was performed by a using triple-quadrupole mass detector at an electrospray ionization interface in positive mode. The precursor to the product ion transition of 441.1 → 379.1 for the qualifier and 441.1 → 423.1 for the quantifier was used for DFX monitoring, whereas 423.1 → 207.1 was used for the internal standard. The validation was performed as per guidelines of bioanalytical method validation, and the evaluated parameters were within the acceptable range. The greenness assessment of the method was evaluated by using AGREE software covering all 12 principles of green analytical chemistry. The final score obtained was 0.78, suggesting excellent greenness of the method. Moreover, Deming regression analysis showed an excellent linear relationship between this method and our previously reported method, and it is suitable for high-throughput analysis for routine application. The proposed method was effectively applied in a pharmacokinetic study of novel formulation (self-nanoemulsifying drug delivery systems) of DFX in rats.

Delafloxacin as a treatment option for community-acquired pneumonia infection

Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality in adults. Bacterial pathogens are recognized to be frequent causative agents, which makes antibacterial treatment crucial for the evolution of these patients. There are several antimicrobial options available in daily practice. However, bacterial resistance is a problem. The chemical, pharmacokinetic, pharmacodynamics, and safety characteristics of delafloxacin, a fluoroquinolone, are discussed. The data from one phase 3 clinical trial evaluating the use of delafloxacin in adults with community-acquired pneumonia is also discussed, along with findings from other meaningful studies. In vitro data have shown that delafloxacin has broad spectrum activity. Results from phase 2 and phase 3 studies have demonstrated that delafloxacin use is safe. International guidelines have recommended respiratory fluoroquinolones as second option for non-severe cases and must be considered in very severe patients not improving to a betalactam/macrolide combination. Delafloxacin was compared to moxifloxacin in the phase 3 community-acquired pneumonia trial. Serious and life-long adverse events due to fluoroquinolones use have been recently reported. Delafloxacin may possibly replace currently available fluoroquinolones, particularly in the treatment of resistant pathogens, such as ciprofloxacin-resistant P. aeruginosa isolates when other drugs are inefficient.

Clinical applications of mesenchymal stromal cell-based therapies for pulmonary diseases: An Update and Concise Review

Lung disorders are a leading cause of morbidity and death worldwide. For many disease conditions, no effective and curative treatment options are available. Mesenchymal stromal cell (MSC)-based therapy is one of the cutting-edge topics in medical research today. It offers a novel and promising therapeutic option for various acute and chronic lung diseases due to its potent and broad-ranging immunomodulatory activities, bacterial clearance, tissue regeneration, and proangiogenic and antifibrotic properties, which rely on both cell-to-cell contact and paracrine mechanisms. This review covers the sources and therapeutic potential of MSCs. In particular, a total of 110 MSC-based clinical applications, either completed clinical trials with safety and early efficacy results reported or ongoing worldwide clinical trials of pulmonary diseases, are systematically summarized following preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, including acute/viral pulmonary disease, community-acquired pneumonia (CAP), chronic obstructive pulmonary disease (COPD), bronchopulmonary dysplasia (BPD), interstitial lung diseases (ILD), chronic pulmonary fibrosis, bronchiolitis obliterans syndrome (BOS) and lung cancer. The results of recent clinical studies suggest that MSCs are a promising therapeutic approach for the treatment of lung diseases. Nevertheless, large-scale clinical trials and evaluation of long-term effects are necessary in further studies.

Serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae isolates from a Phase III community-acquired bacterial pneumonia (CABP) trial

Objectives

To report Streptococcus pneumoniae serotyping and susceptibility data from a recent clinical trial (ML-3341-306) comparing delafloxacin with moxifloxacin in the treatment of adults with community-acquired bacterial pneumonia (CABP).

Methods

Serotyping and susceptibility testing were conducted on 142 baseline S. pneumoniae isolates recovered from subjects participating in a CABP clinical trial.

Results

Overall, 113/142 (79.6%) isolates were vaccine serotypes. 76.8% (109/142) of serotyped isolates were PPSV23 serotypes and 59.9% (85/142) of isolates were PCV13 serotypes. 15.5% (22/142) of serotyped isolates were serotypes not covered by either vaccine; 4.9% (7/142) of tested isolates were non-typeable. The most common serotypes were serotypes 3 (19.0%; 27/142), 19F (9.9%; 14/142) and 23F (7.0%; 10/142). All of the 142 isolates were susceptible to delafloxacin and moxifloxacin, 76.1% were susceptible to azithromycin and 71.8% were susceptible to penicillin. Multidrug resistance was found among 19A (4/5; 80%), 6A (1/4; 25%), 6B (1/4; 25%), 14 (1/4; 25%), 19F (1/14; 7.1%), and 23F serotypes (2/10; 20%), and among non-typeable S. pneumoniae isolates (1/7; 14.3%).

Conclusions

S. pneumoniae vaccine-targeted serotypes were the main cause of CABP in this Phase 3 CABP study. Fluoroquinolones including delafloxacin remain a good treatment option for CABP in adults caused by S. pneumoniae.

Present and Future Perspectives on Therapeutic Options for Carbapenemase-Producing Enterobacterales Infections

Carbapenem-resistant Enterobacterales (CRE) are included in the list of the most threatening antibiotic resistance microorganisms, being responsible for often insurmountable therapeutic issues, especially in hospitalized patients and immunocompromised individuals and patients in intensive care units. The enzymatic resistance to carbapenems is encoded by different β-lactamases belonging to A, B or D Ambler class. Besides compromising the activity of last-resort antibiotics, CRE have spread from the clinical to the environmental sectors, in all geographic regions. The purpose of this review is to present present and future perspectives on CRE-associated infections treatment.

The Role of Delafloxacin in Patients with Community-Acquired Bacterial Pneumonia in the Outpatient Setting: A Budget Impact Model

Background and Objective

Community-acquired bacterial pneumonia (CABP) affects millions of people each year in the USA. The majority of patients with CABP are treated in the community setting with empirical antimicrobial therapy. Delafloxacin is an anionic fluoroquinolone approved for the treatment of adult patients with CABP. This de novo analysis sought to estimate the budget impact of delafloxacin in the treatment of adult patients with CABP in the outpatient setting from the payer’s perspective.

Methods

A budget impact model (BIM) was developed from the perspective of a US third-party payer to estimate the cost of introducing delafloxacin for the outpatient treatment of CABP over a 1-year time horizon. Population, clinical, and cost inputs were based on the available literature, clinical trial data, and real-world evidence studies. Scenario analyses were conducted to evaluate the potential budget impact among COPD/asthma patients based on the findings from the phase III trial of delafloxacin for CABP, which indicated that patients with COPD or asthma may experience improved effectiveness with delafloxacin compared to moxifloxacin.

Results

In the base-case analysis, with a hypothetical plan of 1,000,000 members, the model estimated that adding delafloxacin to the formulary resulted in a total budget impact of $58,987. This increase was mainly attributed to treatment acquisition costs. In the scenario analysis that was restricted to COPD/asthma patients, adding delafloxacin to the formulary was estimated to result in a total budget impact of $5,042.

Conclusion

The results of the budget impact analyses provide conservative estimates of the impact of adding delafloxacin to outpatient formularies in substitution of moxifloxacin.

Electronic supplementary material

The online version of this article (10.1007/s40261-020-00938-y) contains supplementary material, which is available to authorized users.

The Use of Moxisaxin for Treatment of a Decompensated Cirrhosis Patient with Severe Pulmonary Infection

Introduction: Moxifloxacin is recommended for empirical antibiotic treatment of patients with cirrhosis. However, due to a lack of clinical safety data on moxifloxacin in Child-Pugh C patients, it is unknown how to use moxifloxacin in clinical practice. Case Presentation: A 76-year-old female with decompensated cirrhosis developed pneumonia during hospitalization. She had an initial failure to respond to imipenem/cilastatin + linezolid therapy. After three-day therapy with imipenem/cilastatin + moxisaxin, her infection symptoms rapidly improved. At this time, she presented a poor response with suspected hepatic encephalopathy. Given the worsening clinical symptoms caused by drug hepatotoxicity, moxisaxin was discontinued. Then, her body temperature rapidly raised. Conclusions: Moxisaxin may be a potentially useful antibiotic for hospital-acquired pneumonia in patients with decompensated cirrhosis, but further studies are needed to validate its hepatotoxicity.

In vitro activity of delafloxacin against highly levofloxacin-resistant invasive isolates of Streptococcus pneumoniae

INTRODUCTION

We report the activity of delafloxacin, a new fluoroquinolone with high affinity for both topoisomerase IV and DNA gyrase, against highly-levofloxacin-resistant invasive strains of Streptococcus pneumoniae.

METHODS

A total of 173 highly-levofloxacin-resistant (MIC>32mg/L) S. pneumoniae invasive isolates were studied. The strains were isolated from blood (n=162) and other sterile fluids (n=11). Serotyping was performed by the Pneumotest-Latex and Quellung reaction. Delafloxacin, levofloxacin, penicillin, cefotaxime, erythromycin and vancomycin MICs were determined by the gradient diffusion method following EUCAST guidelines and breakpoints.

RESULTS

Among the isolates, 32.9% were penicillin non-susceptible, 19.7% cefotaxime non-susceptible, and 76.9% erythromycin resistant. All were susceptible to vancomycin. Delafloxacin MIC50 and MIC90 (mg/L) values were 0.064 and 0.12, respectively; 60% (15/25) of serotype 9V isolates showed delafloxacin MICs≥0.12mg/L.

CONCLUSIONS

Delafloxacin was very active against highly-levofloxacin-resistant invasive isolates of S. pneumoniae. Isolates belonging to serotype 9V showed higher delafloxacin MIC values.

Antimicrobial Management of Respiratory Infections in Severe Acute Respiratory Syndrome Coronavirus 2 Patients: Clinical and Antimicrobial Stewardship Programs Conundrums

The role of empirical and even directed antimicrobial management of patients hospitalized with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is problematic; antibiotics are used frequently among these patients to treat confirmed or suspected coinfection or just the symptoms. In the rapidly changing clinical landscape of SARS-CoV-2, there is minimal guidance for selecting appropriate treatment versus non-antimicrobial treatment, and clinicians are pressed to make daily decisions under the stress of absence of data while watching patients deteriorate. We review current data and patterns of antimicrobial use and the potential approach for antimicrobial stewardship in the context of SARS-CoV-2.

Updates on community acquired pneumonia management in the ICU

While the world is grappling with the consequences of a global pandemic related to SARS-CoV-2 causing severe pneumonia, available evidence points to bacterial infection with Streptococcus pneumoniae as the most common cause of severe community acquired pneumonia (SCAP). Rapid diagnostics and molecular testing have improved the identification of co-existent pathogens. However, mortality in patients admitted to ICU remains staggeringly high.

The American Thoracic Society and Infectious Diseases Society of America have updated CAP guidelines to help streamline disease management. The common theme is use of timely, appropriate and adequate antibiotic coverage to decrease mortality and avoid drug resistance. Novel antibiotics have been studied for CAP and extend the choice of therapy, particularly for those who are intolerant of, or not responding to standard treatment, including those who harbor drug resistant pathogens. In this review, we focus on the risk factors, microbiology, site of care decisions and treatment of patients with SCAP.

Where is Chlamydophila pneumoniae pneumonia?

BACKGROUND

Molecular diagnostic methods have recently gained widespread use, and consequently, the importance of viral pathogens in community-acquired pneumonia (CAP) has undergone re-evaluation. Under these circumstances, the role of Chlamydophila pneumoniae as a pathogen that causes CAP also needs to be reviewed.

METHODS

We reviewed articles that contained data on the frequency of identification of C. pneumoniae pneumonia as a causative pathogen for CAP. The articles were identified by performing a search in PubMed with the keywords "community-acquired pneumonia" and "pathogen".

RESULTS

Sixty-three articles were identified. The reviewed articles demonstrated that the rates of identification of C. pneumoniae as the causative pathogen for CAP were significantly lower in assessments based on polymerase chain reaction (PCR) methods than in those based on serological methods. In some studies, it was possible to compare both serological and PCR methods directly using the same set of samples.

CONCLUSIONS

The use of PCR methods, including multiplex PCR assays, has revealed that C. pneumoniae may play a limited role as a pathogen for CAP.

A Narrative Review of Early Oral Stepdown Therapy for the Treatment of Uncomplicated Staphylococcus aureus Bacteremia: Yay or Nay?

Historically, intravenous (IV) antibiotics have been the cornerstone of treatment for uncomplicated Staphylococcus aureus bacteremia (SAB). However, IV antibiotics are expensive, increase the rates of hospital readmission, and can be associated with catheter-related complications. As a result, the potential role of oral antibiotics in the treatment of uncomplicated SAB has become a subject of interest. This narrative review article aims to summarize key arguments for and against the use of oral antibiotics to complete treatment of uncomplicated SAB and evaluates the available evidence for specific oral regimens. We conclude that evidence suggests that oral step-down therapy can be an alternative for select patients who meet the criteria for uncomplicated SAB and will comply with medical treatment and outpatient follow-up. Of the currently studied regimens discussed in this article, linezolid has the most support, followed by fluoroquinolone plus rifampin.

A Phase 3 Study to Compare Delafloxacin With Moxifloxacin for the Treatment of Adults With Community-Acquired Bacterial Pneumonia (DEFINE-CABP)

BACKGROUND

The clinical and economic burden of community-acquired bacterial pneumonia (CABP) is significant and is anticipated to increase as the population ages and pathogens become more resistant. Delafloxacin is a fluoroquinolone antibiotic approved in the United States for the treatment of adults with acute bacterial skin and skin structure infections. Delafloxacin's shape and charge profile uniquely impact its spectrum of activity and side effect profile. This phase 3 study compared the efficacy and safety of delafloxacin with moxifloxacin for the treatment of CABP.

METHODS

A randomized, double-blind, comparator-controlled, multicenter, global phase 3 study compared the efficacy and safety of delafloxacin 300 mg twice daily or moxifloxacin 400 mg once daily in adults with CABP. The primary end point was early clinical response (ECR), defined as improvement at 96 (±24) hours after the first dose of study drug. Clinical response at test of cure (TOC) and microbiologic response were also assessed.

RESULTS

In the intent-to-treat analysis population (ITT), ECR rates were 88.9% in the delafloxacin group and 89.0% in the moxifloxacin group. Noninferiority of delafloxacin compared with moxifloxacin was demonstrated. At TOC in the ITT population, the success rates were similar between groups. Treatment-emergent adverse events that were considered at least possibly related to the study drug occurred in 65 subjects (15.2%) in the delafloxacin group and 54 (12.6%) in the moxifloxacin group.

CONCLUSIONS

Intravenous/oral delafloxacin monotherapy is effective and well tolerated in the treatment of adults with CABP, providing coverage for Gram-positive, Gram-negative, and atypical pathogens.

CLINICALTRIALSGOV IDENTIFIER

NCT03534622.