Daptomycin use in neutropenic patients with documented gram-positive infections

Infections in Hospitalized Cancer Patients

Cancer patients are at an increased risk of developing infections that are primarily treatment-driven but may also be malignancy-driven. While cancer treatments such as chemotherapy, radiotherapy, and surgery have been known to improve malignancy morbidity and mortality, they also have the potential to weaken immune defenses and induce periods of severe cytopenia. These adverse effects pave the way for opportunistic infections to complicate a hospitalized cancer patient's clinical course. Understanding the risk each patient inherently has for developing a bacterial, fungal, or viral infection is critical to choosing the correct prophylactic treatment in conjunction with their scheduled cancer therapy. This review discusses the most common types of infections found in hospitalized cancer patients as well as the current guidelines for prophylactic and antimicrobial treatment in cancer patients. In addition, it describes the interaction between antibiotics and cancer therapies for consideration when treating infection in a cancer patient.

Febrile Neutropenia in Transplant Recipients

Febrile neutropenic patients are at increased risk of developing infections. During the initial stages of neutropenia, most of these infections are bacterial. The spectrum of bacterial infections depends to some extent on whether or not patients receive antimicrobial prophylaxis when neutropenic. Since most transplant recipients do, Gram-positive organisms predominate, due to the fact prophylaxis is directed primarily against Gram-negative organisms. Staphylococcus species (often methicillin-resistant), Streptococcus species (viridans group streptococci, beta-hemolytic streptococci), and Enterococcus species (including vancomycin-resistant strains) are isolated most often. Therefore, potent empiric Gram-positive coverage is recommended by many in this setting. Escherichia coli, Pseudomonas aeruginosa, and Klebsiella species are the most common Gram-negative pathogens isolated. Non-fermentative Gram-negative bacilli (Stenotrophomonas maltophilia, Acinetobacter species) are emerging as important pathogens. Many of these organisms acquire multiple mechanisms of resistance that render them multidrug resistant. The administration of prompt, broad-spectrum, empiric, antimicrobial therapy is essential and is generally based on local epidemiology and susceptibility/resistance patterns. Response rate to the initial regimen is generally in the range of 75–85%. Fungal infections develop in patients with prolonged neutropenia (greater than 7–10 days). Candida species and Aspergillus species are the predominant fungal pathogens, although many other fungi are opportunistic pathogens in this setting. Fungal infections are seldom documented microbiologically or on histopathology, and the administration of empiric antifungal therapy, when such infections are suspected, is the norm. Therapy is often prolonged, and outcomes are still suboptimal. The importance of infection control and antimicrobial stewardship cannot be overemphasized.

Daptomycin vs. glycopeptides in the treatment of febrile neutropenia: results of the Izmir matched cohort study

PURPOSE

In this multicentre, retrospective, matched cohort study we aimed to evaluate the outcomes of neutropenic fever cases that were treated with daptomycin or a glycopeptide (vancomycin or teicoplanin).

METHODS

Data and outcomes of adult (aged > 18-years old) patients with neutropenic fever [(1) without clinical and radiological evidence of pneumonia, (2) who were treated with daptomycin or a glycopeptide (teicoplanin or vancomycin) for any reason and for at least 72 h] were extracted from the hospital databases. Matching was performed with all of the three following criteria: (1) underlying disease, (2) reason for starting daptomycin or glycopeptide (microbiologic evidence vs. microbiologic evidence, clinical infection vs. clinical infection and empirical therapy vs. empirical therapy) and (3) neutropenic status.

RESULTS

Overall 128 patients [(69/123) (56.1%) in the daptomycin cohort (D) and 59/123 (48%) in the glycopeptide cohort (G)] had a resolution of fever at the end of 72 h antibiotic treatment (p = 0.25). There was no significant difference in cured, improved and (cured + improved) rates between (D) and (G) cohorts as well as fever of unknown origin cases or microbiologically confirmed infections or clinically defined infections subgroups (p > 0.05). There was also no significant difference (p > 0.05), in terms of persistent response in the (D) versus (G) cohorts, CONCLUSIONS: These findings suggest that although not better, daptomycin efficacy is comparable to vancomycin if used as empiric therapy in the treatment of adult febrile neutropenia. We conclude that daptomycin may be used at least as a salvage therapy alternative to glycopeptides in the treatment of adult febrile neutropenia cases. A large, randomized-controlled trial may further consolidate the evidence related to this question.

Antibacterial Resistance in Patients with Hematopoietic Stem Cell Transplantation

Recipients of hematopoietic stem cell transplantation (HSCT) are at substantial risk of bacterial, fungal, viral, and parasitic infections depending on the time elapsed since transplantation, presence of graft-versus-host disease (GVHD), and the degree of immunosuppression. Infectious complications in HSCT recipients are associated with high morbidity and mortality. Bacterial infections constitute the major cause of infectious complications, especially in the early post-transplant period. The emergence of antibacterial resistance complicates the management of bacterial infections in this patient group. Multidrug-resistant bacterial infections in this group of patients have attracted considerable interest and may lead to significant morbidity and mortality. Empirical antibacterial therapy in patients with HSCT and febrile neutropenia has a critical role for survival and should be based on local epidemiology. This review attempts to provide an overview of risk factors and epidemiology of emerging resistant bacterial infections and their management in HSCT recipients.

Clinical Characteristics of Methicillin-resistant Coagulase-negative Staphylococcal Bacteremia in a Tertiary Hospital

Objective Coagulase-negative staphylococci are among the most frequently isolated microorganisms in blood cultures. The aim of this study was to assess [1] the clinical characteristics of methicillin-resistant, coagulase-negative staphylococci bacteremia and [2] the susceptibility of the isolated bacteria to glycopeptides. Methods We retrospectively reviewed the medical records of 70 patients from whom methicillin-resistant coagulase-negative staphylococci had been isolated at Osaka City University Hospital between January 2010 and December 2013. We evaluated the patients' background, severity and prognosis of the disease, and the susceptibility of the isolated methicillin-resistant coagulase-negative staphylococci to glycopeptides. Results Out of the 70 patients tested, 28 (40.0%) had leukemia, and 36 (51.4%) had been treated for febrile neutropenia. Infection with Staphylococcus epidermidis accounted for 78.6% of patients. Thirty-nine cases (55.7%) were related to intravascular catheters, and 39 (55.7%) were treated using teicoplanin as a first-line therapy. The 30-day mortality rate was 4.3%. Regarding susceptibility, 20% of all isolates were non-susceptible to teicoplanin. According to multivariate analyses, it was observed that premedication using glycopeptides was independently associated with teicoplanin non-susceptibility (p=0.03; hazard ratio = 5.64; 95% confidence interval, 1.16-26.76). Conclusion Our results suggest that clinicians must use glycopeptides appropriately to prevent the development of further antibiotic resistance in methicillin-resistant coagulase-negative staphylococci.

Bloodstream infections in neutropenic cancer patients: A practical update

Bloodstream infections (BSI) are among the most frequent complications in neutropenic cancer patients and, if caused by Gram-negative rods, are associated with high mortality. Thus, fever during neutropenia warrants prompt empirical antibiotic therapy which should be active against the most frequent Gram-negatives. In the last decade, there has been a worldwide increase in multidrug resistant (MDR) strains. In these cases, the traditional choices such as oral therapy, ceftazidime, cefepime, piperacillin-tazobactam, or even carbapenems, might be ineffective. Therefore novel de-escalation approach has been proposed for patients who are at high risk for infections due to MDR bacteria. It consists of starting antibiotics which cover the most probable resistant strain but it is narrowed down after 72 hours if no MDR pathogen is isolated. With increasing bacterial resistance, the benefit of fluoroquinolone prophylaxis during prolonged neutropenia remains to be confirmed. Antibiotic stewardship and infection control programs are mandatory in every cancer center.

Real-world daptomycin use across wide geographical regions: results from a pooled analysis of CORE and EU-CORE

Background

Pooled data from two large registries, Cubicin^® Outcomes Registry and Experience (CORE; USA) and European Cubicin^® Outcomes Registry and Experience (EU-CORE; Europe, Latin America, and Asia), were analyzed to determine the characteristics and clinical outcomes of daptomycin therapy in patients with Gram-positive infections across wide geographical regions.

Methods

Patients receiving at least one dose of daptomycin between 2004 and 2012 for the treatment of Gram-positive infections were included. Clinical success was defined as an outcome of ‘cured’ or ‘improved’. Post-treatment follow-up data were collected for a subset of patients (CORE: osteomyelitis and orthopedic foreign body device infection; EU-CORE: endocarditis, intracardiac/intravascular device infection, osteomyelitis, and orthopedic device infection). Safety was assessed for up to 30 days after daptomycin treatment.

Results

In 11,557 patients (CORE, 5482; EU-CORE, 6075) treated with daptomycin (median age, 62 [range, 1–103] years), the most frequent underlying conditions were cardiovascular disease (54.7 %) and diabetes mellitus (28.0 %). The most commonly treated primary infections were complicated skin and soft tissue infection (cSSTI; 31.2 %) and bacteremia (21.8 %). The overall clinical success rate was 77.2 % (uncomplicated SSTI, 88.3 %; cSSTI, 81.0 %; osteomyelitis, 77.7 %; foreign body/prosthetic infection (FBPI), 75.9 %; endocarditis, 75.4 %; and bacteremia, 69.5 %). The clinical success rate was 79.1 % in patients with Staphylococcus aureus infections (MRSA, 78.1 %). An increasing trend of high-dose daptomycin (>6 mg/kg/day) prescribing pattern was observed over time. Clinical success rates were higher with high-dose daptomycin treatment for endocarditis and FBPI. Adverse events (AEs) and serious AEs possibly related to daptomycin therapy were reported in 628 (5.4 %) and 133 (1.2 %) patients, respectively.

Conclusions

The real-world data showed that daptomycin was effective and safe in the treatment of various Gram-positive infections, including those caused by resistant pathogens, across wide geographical regions.

In vitro activity of dalbavancin and five comparator agents against common and uncommon Gram-positive organisms isolated from cancer patients

Dalbavancin is a long acting, bactericidal lipoglycopeptide. Its in vitro activity was compared with that of vancomycin, daptomycin, linezolid, trimethoprim/sulfamethoxazole (TMP/SMX) and levofloxacin against 241 Gram-positive organisms isolated from cancer patients. The rank order of potency for the glycopeptides based on MIC90 (μg ml(-1)), that is, the concentration of antimicrobial agent required to inhibit 90% of isolates tested was dalbavancin (0.12 μg ml(-1))>daptomycin (1.0 μg ml(-1))>vancomycin (2.0 μg ml(-1)) for coagulase-negative staphylococci and Staphylococcus aureus isolates (including methicillin-susceptible (MSSA) and methicillin-resistant (MRSA) strains). Dalbavancin had potent activity against staphylococcal isolates with vancomycin MICs⩾1.0 μg ml(-1). TMP/SMX also had potent activity against staphylococci including methicillin-resistant strains, whereas levofloxacin had moderate to poor anti-staphylococcal activity. Dalbavancin also exhibited more potent activity than vancomycin and daptomycin against Bacillus spp., Corynebacterium spp., Micrococcus spp. and various streptococci (including Streptococcus pneumoniae, viridans group streptococci (VGS), beta-hemolytic streptococci and gamma-hemolytic streptococci). MBC determinations showed that dalbavancin had potent bactericidal activity against MRSA with no tolerance being detected. These data suggest that dalbavancin may be considered as an alternative to vancomycin, especially in institutions wherein a substantial proportion of infections are caused by organisms with vancomycin MICs⩾1.0 μg ml(-1).

The prevention and management of infections due to multidrug resistant organisms in haematology patients

Infections due to resistant and multidrug resistant (MDR) organisms in haematology patients and haematopoietic stem cell transplant recipients are an increasingly complex problem of global concern. We outline the burden of illness and epidemiology of resistant organisms such as gram-negative pathogens, vancomycin-resistant Enterococcus faecium (VRE), and Clostridium difficile in haematology cohorts. Intervention strategies aimed at reducing the impact of these organisms are reviewed: infection prevention programmes, screening and fluoroquinolone prophylaxis. The role of newer therapies (e.g. linezolid, daptomycin and tigecycline) for treatment of resistant and MDR organisms in haematology populations is evaluated, in addition to the mobilization of older agents (e.g. colistin, pristinamycin and fosfomycin) and the potential benefit of combination regimens.

Daptomycin for Gram-positive Infections in Patients with Neutropenia: Clinical Experience from a European Outcomes Registry

Introduction

The aim of this analysis was to describe in real-world settings the clinical outcomes and safety associated with daptomycin treatment in patients with neutropenia and Gram-positive infections.

Methods

Patients with an absolute neutrophil count (ANC) ≤1000 cells/mm³ who received at least one dose of daptomycin between 2006 and 2012 were selected from a non-interventional, multicenter, retrospective registry (European Cubicin^® Outcome Registry and Experience; EU-CORE^SM).

Results

Of the 6075 patients enrolled in EU-CORE, 446 (7.3%) had an ANC ≤ 1000 cells/mm³ at baseline or during daptomycin therapy; they were all included in efficacy and safety populations. Half of the patients had severe neutropenia (ANC ≤ 100 cells/mm³). Most patients had hematologic malignancy (60.5%), an immunosuppressed state (39.7%) or had undergone a transplant (27.8%). The most common primary infections were bacteremia (42.2%) and complicated skin and soft tissue infection (13.9%). Cultures were positive for 68.6% (254/370) of patients with available culture results; coagulase-negative staphylococci (43.7%; 111/254) and Staphylococcus aureus (18.9%; 48/254) were the most commonly isolated primary pathogens. Median duration of daptomycin therapy was 10.0 (range 1–98) days. Most patients (82.8%) received antibiotics concomitantly with daptomycin; the most common were carbapenems (51.2%), penicillins (42.1%), and aminoglycosides (19.9%). The overall clinical success rate (cured or improved) associated with daptomycin was 77.1%. Adverse events possibly related to daptomycin treatment were reported in seven (1.6%) patients and led to drug discontinuation in 27 (6.1%) patients.

Conclusion

The study results suggest that daptomycin is an effective therapeutic option for the treatment of a broad range of Gram-positive infections in patients with neutropenia, and has a good safety profile.

Funding

This study was funded by Novartis Pharma AG.

Electronic supplementary material

The online version of this article (doi:10.1007/s12325-015-0231-3) contains supplementary material, which is available to authorized users.

Invasive gram-positive bacterial infection in cancer patients

Systematic studies have shown that gram-positive organisms are the leading cause of invasive bacterial disease in patients with cancer. A broad range of gram-positive bacteria cause serious infections in the cancer patient with the greatest burden of disease being due to staphylococci, streptococci, and enterococci. The evolution of cancer therapy and the changing epidemiology of major gram-positive pathogens mean that ongoing efforts are needed to understand and mitigate the impact of these bacteria in patients with malignancy. The development of novel antibacterials, optimization of treatment approaches, implementation of improved vaccines, and manipulation of the microbiome are all active areas of investigation in the goal of improving the survival of the cancer patient through amelioration of the disease burden of gram-positive bacteria.

Daptomycin for the treatment of bacteraemia due to vancomycin-resistant enterococci

Treatment of severe infections caused by vancomycin-resistant enterococci (VRE) is challenging due to the scarcity of reliable therapeutic alternatives. In this context, daptomycin (DAP), a lipopeptide antibiotic, has emerged as an interesting alternative as it is one of the few compounds that retain in vitro bactericidal activity against VRE isolates, although it has not been approved for this purpose by regulatory agencies. In this review, we will summarise the clinical, animal and in vitro evidence evaluating the efficacy of DAP for the management of deep-seated VRE infections. In addition, we will address important clinical concerns such as the emergence of DAP resistance during therapy and reports of therapeutic failure with DAP monotherapy. Finally, we will discuss possible future strategies (such as the use of higher doses and/or combination therapies) to optimise the use of this antibiotic against VRE.

Daptomycin activity tested against 164457 bacterial isolates from hospitalised patients: summary of 8 years of a Worldwide Surveillance Programme (2005-2012)

We report the results of 8 years (2005-2012) of the Daptomycin Surveillance Programme Worldwide. Consecutive non-duplicate bacterial isolates (prevalence design) were collected from patients with documented infections in 410 medical centres and were susceptibility tested by reference broth microdilution methods. A total of 164457 Gram-positive isolates were evaluated, including 97542 Staphylococcus aureus, 21413 coagulase-negative staphylococci (CoNS), 29619 enterococci and 15883 β-haemolytic streptococci. The prevalence of daptomycin-non-susceptible isolates was extremely low for all species in all geographic regions. Overall, the highest occurrence of non-susceptible isolates was observed among CoNS (0.19%), followed by Enterococcus faecium (0.18%), S. aureus (0.05%), Enterococcus faecalis (0.02%) and β-haemolytic streptococci (0.00%). Moreover, no trend towards increased daptomycin resistance (non-susceptibility) was observed for any species in any geographic region during the study interval. Against S. aureus, the daptomycin MIC(50/90) was 0.25/0.5 mg/L in all geographic regions (99.95% susceptible overall). Only 53 daptomycin-non-susceptible S. aureus isolates were observed and the vast majority (49; 92.5%) had a daptomycin MIC value only 1 log(2) dilution above the published susceptible breakpoint. Daptomycin was also active against CoNS (MIC(50/90), 0.25/0.5 mg/L; 99.81% susceptible), E. faecalis (MIC(50/90), 1/2 mg/L; 99.98% susceptible), E. faecium (MIC(50/90), 2/4 mg/L; 99.82% susceptible) including vancomycin-non-susceptible isolates (4521 isolates; MIC(50/90), 2/2 mg/L; 99.76% susceptible), and β-haemolytic streptococci (MIC(50/90), ≤0.06/0.25 mg/L; 100.0% susceptible). In conclusion, daptomycin has remained very active against indicated species worldwide, and no significant year-to-year or regional variation in daptomycin activity has been detected.