Predictors of SARS-CoV-2 Omicron breakthrough infection after receipt of AZD7442 (tixagevimab-cilgavimab) for pre-exposure prophylaxis among hematologic malignancy patients.

AZD7442 (tixagevimab-cilgavimab) is a combination of two human monoclonal antibodies for pre-exposure prophylaxis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among high-risk patients who do not mount a reliable vaccine response. Foremost among these are hematologic malignancy patients with limited clinical trial or realworld experience to assess the effectiveness of this combination treatment since the emergence of Omicron and its subvariants. We performed a retrospective study of 892 high-risk hematologic malignancy patients who received AZD7442 at Memorial Sloan Kettering Cancer Center in New York City from January 1, 2022 to July 31, 2022. We evaluated demographic, clinical, and laboratory characteristics and performed regression analyses to evaluate risk factors for breakthrough infection. We also evaluated the impact of updated AZD7442 dosing regimens on the risk of breakthrough infection. Among 892 patients, 98 (10.9%) had a breakthrough infection during the study period. A majority received early outpatient treatment (82%) and eventually eight (8.2%) required hospitalization for management of Coronavirus Disease 2019 (COVID-19), with a single instance of severe COVID-19 and death. Patients who received a repeat dose or a higher firsttime dose of AZD7442 had a lower incidence of breakthrough infection. Univariate analyses did not reveal any significant predictors of breakthrough infection. While AZD7442 is effective at reducing SARS-CoV-2 breakthrough infection in patients with hematologic malignancies, no risk factors reliably predicted risk of infection. Patients who received updated dosing regimens as per Food and Drug Administration guidelines had better protection against breakthrough infection.

Bacterial infections and antibiotic utilization varies by coronavirus disease 19 (COVID-19) severity in hospitalized cancer patients: Analysis from the first phase of the pandemic.

OBJECTIVE: To characterize bacterial infections and antibiotic utilization in hospitalized cancer patients with coronavirus disease 2019 (COVID-19). DESIGN: Retrospective cohort study. SETTING: Tertiary cancer center in New York City. PATIENTS: Hospitalized cancer patients ≥18 years with COVID-19 between March 1, 2020, and May 31, 2020. METHODS: Patients were classified with mild COVID-19 (ie, with room air), moderate COVID-19 (ie, using nasal cannula oxygen), or severe COVID-19 (ie, using high-flow oxygen or mechanical ventilation). The primary outcome was bacterial infection rate within 30 days of COVID-19 onset. Secondary outcomes included the proportion of patients receiving antibiotics and antibiotic length of therapy (LOT). RESULTS: Of 358 study patients, 133 had mild COVID-19, 97 had moderate COVID-19, and 128 had severe COVID-19. Of 358 patients, 234 (65%) had a solid tumor. Also, 200 patients (56%) had 245 bacterial infections, of which 67 (27%) were microbiologically confirmed. The proportion of patients with bacterial infection increased with COVID-19 severity: mild (n = 47, 35%) versus moderate (n = 49, 51%) versus severe (n = 104, 81%) (P < .0001). Also, 274 (77%) received antibiotics for a median of 4 days. The median antibiotic LOTs were 7 days with 1 infection and 20 days with multiple infections (P < .0001). Antibiotic durations were 1 day for patients with mild COVID-19, 4 days for patients with moderate COVID-19, and 8 days for patients with severe COVID-19 (P < .0001). CONCLUSIONS: Hospitalized cancer patients with COVID-19 had a high rate of bacterial infection. As COVID-19 severity increased, the proportion of patients diagnosed with bacterial infection and given antibiotics increased. In mild COVID-19 cases, antibiotic LOT was short, suggesting that empiric antibiotics can be safely avoided or discontinued in this group.

Predictors of Coronavirus Disease 2019 Hospitalization After Sotrovimab in Patients With Hematologic Malignancy During the BA.1 Omicron Surge.

BACKGROUND: Sotrovimab is an anti-spike neutralization monoclonal antibody developed to reduce the risk of coronavirus disease 2019 (COVID-19) progression and advancement to hospitalization in high-risk patients. Currently, there is limited research describing the association of sotrovimab treatment in patients with hematologic malignancy and the predictive factors of hospitalization. METHODS: We performed an observational study of 156 consecutive cancer patients who received sotrovimab at Memorial Sloan Kettering Cancer Center in New York City during the BA.1 Omicron surge. We evaluated the demographic, clinical, and laboratory characteristics of the patients who had subsequent COVID-19-related hospitalization(s) compared to those who did not. RESULTS: Among the 156 study patients, 17 (11%) were hospitalized, of whom 4 were readmitted for COVID-19-related complications; 3 deaths were attributed to COVID-19. Results from multivariable logistic regression show that significant factors associated with hospitalization include patients on anti-CD20 therapy (adjusted odds ratio [aOR], 5.59 [95% confidence interval {CI}, 1.73-18.12]; P = .004) and with relapse/refractory disease (aOR, 5.69 [95% CI, 1.69-19.16]; P = .005). Additionally, whole genome sequencing of severe acute respiratory syndrome coronavirus 2 detected high occurrences of mutations in the spike gene associated with treatment-related resistance longitudinal samples from 11 patients treated with sotrovimab. CONCLUSIONS: While sotrovimab is effective at reducing COVID-19 hospitalization and disease severity in patients with hematologic malignancy when administered early, patients who received anti-CD20 antibodies showed substantial morbidity. Due to the high potential for resistance mutation to sotrovimab and increased morbidity in patients on anti-CD20 therapy, combination treatment should be explored to determine whether it provides added benefits compared to monotherapy.

Biguanides enhance antifungal activity against Candida glabrata.

Candida spp. are the fourth leading cause of nosocomial blood stream infections in North America. Candida glabrata is the second most frequently isolated species, and rapid development of antifungal resistance has made treatment a challenge. In this study, we investigate the therapeutic potential of metformin, a biguanide with well-established action for diabetes, as an antifungal agent against C. glabrata. Both wild type and antifungal-resistant isolates of C. glabrata were subjected to biguanide and biguanide-antifungal combination treatment. Metformin, as well as other members of the biguanide family, were found to have antifungal activity against C. glabrata, with MIC50 of 9.34 ± 0.16 mg/mL, 2.09 ± 0.04 mg/mL and 1.87 ± 0.05 mg/mL for metformin, phenformin and buformin, respectively. We demonstrate that biguanides enhance the activity of several antifungal drugs, including voriconazole, fluconazole, and amphotericin, but not micafungin. The biguanide-antifungal combinations allowed for additional antifungal effects, with fraction inhibition concentration indexes ranging from 0.5 to 1. Furthermore, metformin was able to lower antifungal MIC50 in voriconazole and fluconazole-resistant clinical isolates of C. glabrata. We also observed growth reduction of C. glabrata with rapamycin and an FIC of 0.84 ± 0.09 when combined with metformin, suggesting biguanide action in C. glabrata may be related to inhibition of the mTOR complex. We conclude that the biguanide class has direct antifungal therapeutic potential and enhances the activity of select antifungals in the treatment of resistant C. glabrata isolates. These data support the further investigation of biguanides in the combination treatment of serious fungal infections.

Clinical and economic implications of urinary tract infections.

INTRODUCTION: Urinary tract infections represent one of the most frequent reasons for hospitalization. As a result of their prevalence from community-based origins as well as those which develop in hospital setting, this constellation of infections represents a tremendous burden to the global healthcare system. Areas covered: Over the last several decades the management of these infections has become more complicated due to the underlying comorbid conditions of the patients as well as escalating antimicrobial resistance to many of the most frequently used oral and parenteral agents. One such example is the emergence of extend spectrum ß-lactamase-producing (ESBL) bacteria that render many of the most frequently utilized oral and parenteral penicillin and cephalosporin based regimens of little clinical utility. As such new treatment strategies are required to effectively manage the growing population of patients with multi-drug resistant bacteria. Expert commentary: Herein, we review some of the current literature which reveals the challenges associated with the contemporary management of UTIs, while presenting strategies such as the implementation of clinical pathways that have the potential to enhance the quality and efficiency of care while reducing the overall cost of care.