Expect the unexpected: endocarditis caused by Legionella feeleii.

We report a fatal case of Legionella feeleii endocarditis in a post-lung transplant patient. The diagnosis was delayed, as routine microbiological testing of nonrespiratory specimens does not account for extrapulmonary Legionella, and urine antigen testing only reliably detects Legionella pneumophila serogroup 1. This case also illustrates the utility of molecular sequencing for blood culture-negative endocarditis.

A Phase 3, Randomized, Double-Blind, Comparator-Controlled Study to Evaluate Safety, Tolerability, and Immunogenicity of V114, a 15-Valent Pneumococcal Conjugate Vaccine, in Allogeneic Hematopoietic Cell Transplant Recipients (PNEU-STEM).

BACKGROUND: Individuals who receive allogeneic hematopoietic cell transplant (allo-HCT) are immunocompromised and at high risk of pneumococcal infections, especially in the months following transplant. This study evaluated the safety and immunogenicity of V114 (VAXNEUVANCE; Merck, Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA), a 15-valent pneumococcal conjugate vaccine (PCV), when given to allo-HCT recipients. METHODS: Participants received 3 doses of V114 or PCV13 (Prevnar 13; Wyeth LLC) in 1-month intervals starting 3-6 months after allo-HCT. Twelve months after HCT, participants received either PNEUMOVAX 23 or a fourth dose of PCV (if they experienced chronic graft vs host disease). Safety was evaluated as the proportion of participants with adverse events (AEs). Immunogenicity was evaluated by measuring serotype-specific immunoglobulin G (IgG) geometric mean concentrations (GMCs) and opsonophagocytic activity (OPA) geometric mean titers (GMTs) for all V114 serotypes in each vaccination group. RESULTS: A total of 274 participants were enrolled and vaccinated in the study. The proportions of participants with AEs and serious AEs were generally comparable between intervention groups, and the majority of AEs in both groups were of short duration and mild-to-moderate intensity. For both IgG GMCs and OPA GMTs, V114 was generally comparable to PCV13 for the 13 shared serotypes, and higher for serotypes 22F and 33F at day 90. CONCLUSIONS: V114 was well tolerated in allo-HCT recipients, with a generally comparable safety profile to PCV13. V114 induced comparable immune responses to PCV13 for the 13 shared serotypes, and was higher for V114 serotypes 22F and 33F. Study results support the use of V114 in allo-HCT recipients. Clinical Trials Registration. clinicaltrials.gov (NCT03565900) and European Union at EudraCT 2018-000066-11.

American Society for Transplantation and Cellular Therapy Series: #5-Management of Clostridioides difficile Infection in Hematopoietic Cell Transplant Recipients.

The Practice Guidelines Committee of the American Society for Transplantation and Cellular Therapy partnered with its Transplant Infectious Disease Special Interest Group to update its 2009 compendium-style infectious disease guidelines for hematopoietic cell transplantation (HCT). A completely new approach was taken with the goal of better serving clinical providers by publishing each standalone topic in the infectious disease series as a concise format of frequently asked questions (FAQ), tables, and figures. Adult and pediatric infectious disease and HCT content experts developed and then answered FAQs and finalized topics with harmonized recommendations that were made by assigning an A through E strength of recommendation paired with a level of supporting evidence graded I through III. This fifth guideline in the series focuses on Clostridioides difficile infection with FAQs that address the prevalence, incidence, clinical features, colonization versus infection, clinical complications, diagnostic considerations, pharmacological therapies for episodic or recurrent infection, and the roles of prophylactic antibiotics, probiotics, and fecal microbiota transplantation.

Initial analysis of viral dynamics and circulating viral variants during the mRNA-1273 Phase 3 COVE trial.

The mRNA-1273 vaccine for coronavirus disease 2019 (COVID-19) demonstrated 93.2% efficacy in reduction of symptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in the blinded portion of the Phase 3 Coronavirus Efficacy (COVE) trial. While mRNA-1273 demonstrated high efficacy in prevention of COVID-19, including severe disease, its effect on the viral dynamics of SARS-CoV-2 infections is not understood. Here, in exploratory analyses, we assessed the impact of mRNA-1273 vaccination in the ongoing COVE trial (number NCT04470427) on SARS-CoV-2 copy number and shedding, burden of disease and infection, and viral variants. Viral variants were sequenced in all COVID-19 and adjudicated COVID-19 cases (n = 832), from July 2020 in the blinded part A of the study to May 2021 of the open-label part B of the study, in which participants in the placebo arm started to receive the mRNA-1273 vaccine after US Food and Drug Administration emergency use authorization of mRNA-1273 in December 2020. mRNA-1273 vaccination significantly reduced SARS-CoV-2 viral copy number (95% confidence interval) by 100-fold on the day of diagnosis compared with placebo (4.1 (3.4-4.8) versus 6.2 (6.0-6.4) log10 copies per ml). Median times to undetectable viral copies were 4 days for mRNA-1273 and 7 days for placebo. Vaccination also substantially reduced the burden of disease and infection scores. Vaccine efficacies (95% confidence interval) against SARS-CoV-2 variants circulating in the United States during the trial assessed in this post hoc analysis were 82.4% (40.4-94.8%) for variants Epsilon and Gamma and 81.2% (36.1-94.5%) for Epsilon. The detection of other, non-SARS-CoV-2, respiratory viruses during the trial was similar between groups. While additional study is needed, these data show that in SARS-CoV-2-infected individuals, vaccination reduced both the viral copy number and duration of detectable viral RNA, which may be markers for the risk of virus transmission.

Remdesivir Versus Standard-of-Care for Severe Coronavirus Disease 2019 Infection: An Analysis of 28-Day Mortality.

BACKGROUND: Remdesivir is approved by the US Food and Drug Administration for the treatment of patients hospitalized with coronavirus disease 2019 (COVID-19) and has been shown to shorten time to recovery and improve clinical outcomes in randomized trials. METHODS: This was the final day 28 comparative analysis of data from a phase 3, randomized, open-label study comparing 2 remdesivir regimens (5 vs 10 days, combined for this analysis [remdesivir cohort]) and a real-world retrospective longitudinal cohort study of patients receiving standard-of-care treatment (nonremdesivir cohort). Eligible patients, aged ≥18 years, had confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), oxygen saturation ≤94% on room air or required supplemental oxygen, with pulmonary infiltrates. Propensity score matching (up to 1:10 ratio) was used to ensure comparable populations. We assessed day 14 clinical recovery (determined using a 7-point ordinal scale) and day 28 all-cause mortality (coprimary endpoints). RESULTS: A total of 368 (remdesivir) and 1399 (nonremdesivir) patients were included in the matched analysis. The day 14 clinical recovery rate was significantly higher among the remdesivir versus the nonremdesivir cohort (65.2% vs 57.1%; odds ratio [OR], 1.49; 95% confidence interval [CI], 1.16-1.90; P = 0.002). The day 28 mortality rate was significantly lower in the remdesivir cohort versus the nonremdesivir cohort (12.0% vs 16.2%; OR, 0.67; 95% CI, 0.47-.95; P = .03). CONCLUSIONS: Remdesivir was associated with significantly higher rates of day 14 clinical recovery, and lower day 28 mortality, compared with standard-of-care treatment in hospitalized patients with COVID-19. These data, taken together, support the use of remdesivir to improve clinical recovery and decrease mortality from SARS-CoV-2 infection.

Remdesivir Use in the Setting of Severe Renal Impairment: A Theoretical Concern or Real Risk?

BACKGROUND: Remdesivir (RDV) is US FDA approved for coronavirus disease 2019 (COVID-19) but not recommended in severe renal impairment (SRI, Creatinine clearance <30mL/min or requiring renal replacement therapy). Few studies have evaluated RDV in patients with SRI. METHODS: Hospitalized patients who received RDV between 1 May 2020 and 31 October 2020 were analyzed in a retrospective chart review. We compared incident adverse events (AEs) in patients with and without SRI, including hepatotoxicity, nephrotoxicity, any reported AE, mortality, and length of stay. RESULTS: Of a total of 135 patients, 20 had SRI. Patients with SRI were significantly older (70 vs 54 years, P = .0001). The incidence of possible AEs was 30% among those with SRI vs 11% without (P = .06). Liver function test (LFT) elevations occurred in 10% vs 4% (P = .28), and serum creatinine (SCr) elevations in 27% vs 6% (P = .02) of patients with SRI vs without, respectively. LFT and SCr elevations were not attributed to RDV in either group. Mortality and length of stay were consistent with historical controls. CONCLUSIONS: RDV AEs occurred infrequently and overall were not significantly different between those with and without SRI. While more of patients with SRI experienced SCr elevations, 3 (75%) patients had acute kidney injury prior to RDV. The use of RDV in this small series of patients with SRI appeared to be relatively safe, and the potential benefit outweighed the theoretical risk of liver or renal toxicity. Additional studies are needed to confirm this finding.

Effect of Remdesivir vs Standard Care on Clinical Status at 11 Days in Patients With Moderate COVID-19: A Randomized Clinical Trial.

Importance: Remdesivir demonstrated clinical benefit in a placebo-controlled trial in patients with severe coronavirus disease 2019 (COVID-19), but its effect in patients with moderate disease is unknown. Objective: To determine the efficacy of 5 or 10 days of remdesivir treatment compared with standard care on clinical status on day 11 after initiation of treatment. Design, Setting, and Participants: Randomized, open-label trial of hospitalized patients with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and moderate COVID-19 pneumonia (pulmonary infiltrates and room-air oxygen saturation >94%) enrolled from March 15 through April 18, 2020, at 105 hospitals in the United States, Europe, and Asia. The date of final follow-up was May 20, 2020. Interventions: Patients were randomized in a 1:1:1 ratio to receive a 10-day course of remdesivir (n = 197), a 5-day course of remdesivir (n = 199), or standard care (n = 200). Remdesivir was dosed intravenously at 200 mg on day 1 followed by 100 mg/d. Main Outcomes and Measures: The primary end point was clinical status on day 11 on a 7-point ordinal scale ranging from death (category 1) to discharged (category 7). Differences between remdesivir treatment groups and standard care were calculated using proportional odds models and expressed as odds ratios. An odds ratio greater than 1 indicates difference in clinical status distribution toward category 7 for the remdesivir group vs the standard care group. Results: Among 596 patients who were randomized, 584 began the study and received remdesivir or continued standard care (median age, 57 [interquartile range, 46-66] years; 227 [39%] women; 56% had cardiovascular disease, 42% hypertension, and 40% diabetes), and 533 (91%) completed the trial. Median length of treatment was 5 days for patients in the 5-day remdesivir group and 6 days for patients in the 10-day remdesivir group. On day 11, patients in the 5-day remdesivir group had statistically significantly higher odds of a better clinical status distribution than those receiving standard care (odds ratio, 1.65; 95% CI, 1.09-2.48; P = .02). The clinical status distribution on day 11 between the 10-day remdesivir and standard care groups was not significantly different (P = .18 by Wilcoxon rank sum test). By day 28, 9 patients had died: 2 (1%) in the 5-day remdesivir group, 3 (2%) in the 10-day remdesivir group, and 4 (2%) in the standard care group. Nausea (10% vs 3%), hypokalemia (6% vs 2%), and headache (5% vs 3%) were more frequent among remdesivir-treated patients compared with standard care. Conclusions and Relevance: Among patients with moderate COVID-19, those randomized to a 10-day course of remdesivir did not have a statistically significant difference in clinical status compared with standard care at 11 days after initiation of treatment. Patients randomized to a 5-day course of remdesivir had a statistically significant difference in clinical status compared with standard care, but the difference was of uncertain clinical importance. Trial Registration: ClinicalTrials.gov Identifier: NCT04292730.

Immunogenicity of Inactivated Varicella Zoster Vaccine in Autologous Hematopoietic Stem Cell Transplant Recipients and Patients With Solid or Hematologic Cancer.

BACKGROUND: In phase 3 trials, inactivated varicella zoster virus (VZV) vaccine (ZVIN) was well tolerated and efficacious against herpes zoster (HZ) in autologous hematopoietic stem cell transplant (auto-HSCT) recipients and patients with solid tumor malignancies receiving chemotherapy (STMc) but did not reduce HZ incidence in patients with hematologic malignancies (HMs). Here, we describe ZVIN immunogenicity from these studies. METHODS: Patients were randomized to ZVIN or placebo (4 doses). Immunogenicity was assessed by glycoprotein enzyme-linked immunosorbent assay (gpELISA) and VZV interferon (IFN)-γ enzyme-linked immunospot (ELISPOT) assay in patients receiving all 4 doses without developing HZ at the time of blood sampling. RESULTS: Estimated geometric mean fold rise ratios (ZVIN/placebo) by gpELISA and IFN-y ELISPOT ~28 days post-dose 4 were 2.02 (95% confidence interval [CI], 1.53-2.67) and 5.41 (95% CI, 3.60-8.12) in auto-HSCT recipients; 1.88 (95% CI, 1.79-1.98) and 2.10 (95% CI, 1.69-2.62) in patients with STMc; and not assessed and 2.35 (95% CI, 1.81-3.05) in patients with HM. CONCLUSIONS: ZVIN immunogenicity was directionally consistent with clinical efficacy in auto-HSCT recipients and patients with STMc even though HZ protection and VZV immunity were not statistically correlated. Despite a lack of clinical efficacy in patients with HM, ZVIN immunogenicity was observed in this population. Immunological results did not predict vaccine efficacy in these 3 populations. CLINICAL TRIAL REGISTRATION: NCT01229267, NCT01254630.

Remdesivir for 5 or 10 Days in Patients with Severe Covid-19.

BACKGROUND: Remdesivir is an RNA polymerase inhibitor with potent antiviral activity in vitro and efficacy in animal models of coronavirus disease 2019 (Covid-19). METHODS: We conducted a randomized, open-label, phase 3 trial involving hospitalized patients with confirmed SARS-CoV-2 infection, oxygen saturation of 94% or less while they were breathing ambient air, and radiologic evidence of pneumonia. Patients were randomly assigned in a 1:1 ratio to receive intravenous remdesivir for either 5 days or 10 days. All patients received 200 mg of remdesivir on day 1 and 100 mg once daily on subsequent days. The primary end point was clinical status on day 14, assessed on a 7-point ordinal scale. RESULTS: In total, 397 patients underwent randomization and began treatment (200 patients for 5 days and 197 for 10 days). The median duration of treatment was 5 days (interquartile range, 5 to 5) in the 5-day group and 9 days (interquartile range, 5 to 10) in the 10-day group. At baseline, patients randomly assigned to the 10-day group had significantly worse clinical status than those assigned to the 5-day group (P = 0.02). By day 14, a clinical improvement of 2 points or more on the ordinal scale occurred in 64% of patients in the 5-day group and in 54% in the 10-day group. After adjustment for baseline clinical status, patients in the 10-day group had a distribution in clinical status at day 14 that was similar to that among patients in the 5-day group (P = 0.14). The most common adverse events were nausea (9% of patients), worsening respiratory failure (8%), elevated alanine aminotransferase level (7%), and constipation (7%). CONCLUSIONS: In patients with severe Covid-19 not requiring mechanical ventilation, our trial did not show a significant difference between a 5-day course and a 10-day course of remdesivir. With no placebo control, however, the magnitude of benefit cannot be determined. (Funded by Gilead Sciences; GS-US-540-5773 ClinicalTrials.gov number, NCT04292899.).

Exploratory Evaluation of Bezlotoxumab on Outcomes Associated With Clostridioides difficile Infection in MODIFY I/II Participants With Cancer.

BACKGROUND: The incidence of Clostridioides difficile infection (CDI) is reportedly higher and the cure rate lower in individuals with cancer vs those without cancer. An exploratory post hoc analysis of the MODIFY I/II trials (NCT01241552/NCT01513239) investigated how bezlotoxumab affected the rate of CDI-related outcomes in participants with cancer. METHODS: Participants received a single infusion of bezlotoxumab (10 mg/kg) or placebo during anti-CDI antibacterial treatment. A post hoc analysis of CDI-related outcomes was conducted in subgroups of MODIFY I/II participants with and without cancer. RESULTS: Of 1554 participants in the modified intent-to-treat (mITT) population, 382 (24.6%) were diagnosed with cancer (bezlotoxumab 190, placebo 192). Of participants without cancer, 591 and 581 received bezlotoxumab and placebo, respectively. In the placebo group, initial clinical cure (ICC) was achieved by fewer cancer participants vs participants without cancer (71.9% vs 83.1%; absolute difference, -11.3%; 95% CI, -18.6% to -4.5%); however, CDI recurrence (rCDI) rates were similar in cancer (30.4%) and noncancer (34.0%) participants. In participants with cancer, bezlotoxumab treatment had no effect on ICC rate compared with placebo (76.8% vs 71.9%), but resulted in a statistically significant reduction in rCDI vs placebo (17.8% vs 30.4%; absolute difference, -12.6%; 95% CI, -22.5% to -2.7%). CONCLUSIONS: In this post hoc analysis of participants with cancer enrolled in MODIFY I/II, the rate of rCDI in bezlotoxumab-treated participants was lower than in placebo-treated participants. Additional studies are needed to confirm these results. CLINICAL TRIAL REGISTRATION: MODIFY I (NCT01241552), MODIFY II (NCT01513239).

A Phase 2b, Randomized, Double-blind, Placebo-Controlled Multicenter Study Evaluating Antiviral Effects, Pharmacokinetics, Safety, and Tolerability of Presatovir in Hematopoietic Cell Transplant Recipients with Respiratory Syncytial Virus Infection of the Lower Respiratory Tract.

BACKGROUND: Presatovir significantly reduced nasal viral load, signs, and symptoms of respiratory syncytial virus (RSV) infection in a human challenge study. We evaluated presatovir in hematopoietic-cell transplant (HCT) recipients with RSV lower respiratory tract infection (LRTI). METHODS: Patients with confirmed RSV in upper and lower respiratory tract and new chest X-ray abnormalities were randomized (1:1), stratified by supplemental oxygen and ribavirin use, to receive oral presatovir 200 mg or placebo every 4 days for 5 doses. The primary endpoint was time-weighted average change in nasal RSV viral load through day 9. Secondary endpoints included supplemental oxygen-free days, incident respiratory failure requiring mechanical ventilation, and all-cause mortality. RESULTS: From January 31, 2015, to March 20, 2017, 60 patients from 17 centers were randomized (31 presatovir, 29 placebo); 59 received study treatment (50 allogeneic, 9 autologous HCT). In the efficacy population (29 presatovir, 28 placebo), presatovir treatment did not significantly reduce time-weighted average change in viral load (-1.12 vs -1.09 log10 copies/mL; treatment difference -0.02 log10 copies/mL, 95% confidence interval: -.62, .57; P = .94), median supplemental oxygen-free days (26 vs 28 days, P = .84), incident respiratory failure (10.3 vs 10.7%, P = .98), or all-cause mortality (0 vs 7.1%, P = .19) versus placebo. Adverse events were similar between arms (presatovir 80%, placebo 79%). Resistance-associated substitutions in RSV fusion protein emerged in 6/29 presatovir-treated patients. CONCLUSIONS: Presatovir treatment was well tolerated in HCT patients with RSV LRTI but did not improve virologic or clinical outcomes versus placebo. CLINICAL TRIALS REGISTRATION: www.clinicaltrials.gov, NCT02254421; EudraCT, #2014-002475-29.

A Phase 2, Randomized, Double-blind, Placebo-Controlled Trial of Presatovir for the Treatment of Respiratory Syncytial Virus Upper Respiratory Tract Infection in Hematopoietic-Cell Transplant Recipients.

BACKGROUND: Hematopoietic-cell transplant (HCT) recipients are at risk for severe respiratory syncytial virus (RSV) infection. We evaluated the RSV fusion inhibitor presatovir in a randomized, double-blind, Phase II trial in HCT recipients with RSV upper respiratory tract infections. METHODS: Patients were stratified by lymphopenia (<200/µL) and ribavirin use; were randomized, stratified by lymphopenia (<200/µL) and ribavirin use, to receive oral presatovir at 200 mg or a placebo on Days 1, 5, 9, 13, and 17, and were followed through Day 28. The coprimary efficacy endpoints were the time-weighted average change in the nasal RSV viral load between Days 1 and 9 and the proportion of patients developing lower respiratory tract complications (LRTCs) through Day 28. RESULTS: From 23 January 2015 to 16 June 2017, 189 patients were randomly assigned to treatment (96 to presatovir and 93 to the placebo). Presatovir treatment, compared with the placebo treatment, did not significantly affect (prespecified α = 0.01) a time-weighted average decline in the RSV viral load from Day 1 to 9 (treatment difference, -0.33 log10 copies/mL; 95% confidence interval [CI] -.64 to -.02 log10 copies/mL; P = .040) or the progression to LRTC (11.2% vs 19.5%, respectively; odds ratio, 0.50; 95% CI, .22-1.18; P = .11). In a post hoc analysis among patients with lymphopenia, presatovir decreased LRTC development by Day 28 (2/15 [13.3%] vs 9/14 [64.3%], respectively; P = .008), compared with the placebo. Adverse events were similar for patients receiving presatovir and the placebo. CONCLUSIONS: Presatovir had a favorable safety profile in adult HCT recipients with RSV but did not achieve the coprimary endpoints. Exploratory analyses suggest an antiviral effect among patients with lymphopenia. CLINICAL TRIALS REGISTRATION: NCT02254408; EUDRA-CT#2014-002474-36.

Safety and efficacy of inactivated varicella zoster virus vaccine in immunocompromised patients with malignancies: a two-arm, randomised, double-blind, phase 3 trial.

BACKGROUND: Patients who are immunocompromised because of malignancy have an increased risk of herpes zoster and herpes zoster-related complications. We aimed to investigate the efficacy and safety of an inactivated varicella zoster virus (VZV) vaccine for herpes zoster prevention in patients with solid tumour or haematological malignancies. METHODS: This phase 3, two-arm, randomised, double-blind, placebo-controlled, multicentre trial with an adaptive design was done in 329 centres across 40 countries. The trial included adult patients with solid tumour malignancies receiving chemotherapy and those with haematological malignancies, either receiving or not receiving chemotherapy. Patients were randomly assigned (1:1) to receive four doses of VZV vaccine inactivated by γ irradiation or placebo approximately 30 days apart. The patients, investigators, trial site staff, clinical adjudication committee, and sponsor's clinical and laboratory personnel were masked to the group assignment. The primary efficacy endpoint was herpes zoster incidence in patients with solid tumour malignancies receiving chemotherapy, which was assessed in the modified intention-to-treat population (defined as all randomly assigned patients who received at least one dose of inactivated VZV vaccine or placebo). The primary safety endpoint was serious adverse events up to 28 days after the fourth dose in patients with solid tumour malignancies receiving chemotherapy. Safety endpoints were assessed in all patients who received at least one dose of inactivated VZV vaccine or placebo and had follow-up data. This trial is registered (NCT01254630 and EudraCT 2010-023156-89). FINDINGS: Between June 27, 2011, and April 11, 2017, 5286 patients were randomly assigned to receive VZV vaccine inactivated by γ irradiation (n=2637) or placebo (n=2649). The haematological malignancy arm was terminated early because of evidence of futility at a planned interim analysis; therefore, all prespecified haematological malignancy endpoints were deemed exploratory. In patients with solid tumour malignancies in the modified intention-to-treat population, confirmed herpes zoster occurred in 22 of 1328 (6·7 per 1000 person-years) VZV vaccine recipients and in 61 of 1350 (18·5 per 1000 person-years) placebo recipients. Estimated vaccine efficacy against herpes zoster in patients with solid tumour malignancies was 63·6% (97·5% CI 36·4 to 79·1), meeting the prespecified success criterion. In patients with solid tumour malignancies, serious adverse events were similar in frequency across treatment groups, occurring in 298 (22·5%) of 1322 patients who received the vaccine and in 283 (21·0%) of 1346 patients who received placebo (risk difference 1·5%, 95% CI -1·7 to 4·6). Vaccine-related serious adverse events were less than 1% in each treatment group. Vaccine-related injection-site reactions were more common in the vaccine group than in the placebo group. In the haematological malignancy group, VZV vaccine was well tolerated and estimated vaccine efficacy against herpes zoster was 16·8% (95% CI -17·8 to 41·3). INTERPRETATION: The inactivated VZV vaccine was well tolerated and efficacious for herpes zoster prevention in patients with solid tumour malignancies receiving chemotherapy, but was not efficacious for herpes zoster prevention in patients with haematological malignancies. FUNDING: Merck & Co, Inc.

Management of Clostridioides (formerly Clostridium) difficile infection (CDI) in solid organ transplant recipients: Guidelines from the American Society of Transplantation Community of Practice.

These updated guidelines from the American Society of Transplantation Infectious Diseases Community of Practice address the prevention and management of Clostridium difficile infection in solid organ transplant (SOT) recipients. Clostridioides (formerly Clostridium) difficile infection (CDI) is among the most common hospital acquired infections. In SOT recipients, the incidence of CDI varies by type and number or organs transplanted. While a meta-analysis of published literature found the prevalence of postoperative CDI in the general surgical population to be approximately 0.51%, the prevalence of CDI that is seen in the solid organ transplant population ranges from a low of 3.2% in the pancreatic transplant population to 12.7% in those receiving multiple organ transplants. There are no randomized, controlled trials evaluating the management of CDI in the SOT population. Herein is a review and summary of the currently available literature that has been synthesized into updated treatment guidelines for the management of CDI in the SOT population.

A Randomized, Placebo-controlled Trial of Fidaxomicin for Prophylaxis of Clostridium difficile-associated Diarrhea in Adults Undergoing Hematopoietic Stem Cell Transplantation.

Background: Clostridium difficile-associated diarrhea (CDAD) is common during hematopoietic stem-cell transplantation (HSCT) and is associated with increased morbidity and mortality. We evaluated fidaxomicin for prevention of CDAD in HSCT patients. Methods: In this double-blind study, subjects undergoing HSCT with fluoroquinolone prophylaxis stratified by transplant type (autologous/allogeneic) were randomized to once-daily oral fidaxomicin (200 mg) or a matching placebo. Dosing began within 2 days of starting conditioning or fluoroquinolone prophylaxis and continued until 7 days after neutrophil engraftment or completion of fluoroquinolone prophylaxis/clinically-indicated antimicrobials for up to 40 days. The primary endpoint was CDAD incidence through 30 days after study medication. The primary endpoint analysis counted confirmed CDAD, receipt of CDAD-effective medications (for any indication), and missing CDAD assessment (for any reason, including death) as failures; this composite analysis is referred to as "prophylaxis failure" to distinguish from the pre-specified sensitivity analysis, which counted only confirmed CDAD (by toxin immunoassay or nucleic acid amplification test) as failure. Results: Of 611 subjects enrolled, 600 were treated and analyzed. Prophylaxis failure was similar in fidaxomicin and placebo recipients (28.6% vs 30.8%; difference 2.2% [-5.1, 9.5], P = .278). However, most failures were due to non-CDAD events. Confirmed CDAD was lower in fidaxomicin vs placebo recipients (4.3% vs 10.7%; difference 6.4% [2.2, 10.6], P = .0014). Drug-related adverse events occurred in 15.0% of fidaxomicin recipients and 20.0% of placebo recipients. Conclusions: While no difference was demonstrated between arms in the primary analysis, results of the sensitivity analysis demonstrated that fidaxomicin significantly reduced the incidence of CDAD in HSCT recipients. Clinical Trials Registration: NCT01691248.

A Randomized, Double-Blind, Placebo-Controlled Phase 3 Trial of Oral Brincidofovir for Cytomegalovirus Prophylaxis in Allogeneic Hematopoietic Cell Transplantation.

Cytomegalovirus (CMV) infection is a common complication of allogeneic hematopoietic cell transplantation (HCT). In this trial, we randomized adult CMV-seropositive HCT recipients without CMV viremia at screening 2:1 to receive brincidofovir or placebo until week 14 post-HCT. Randomization was stratified by center and risk of CMV infection. Patients were assessed weekly through week 15 and every third week thereafter through week 24 post-HCT. Patients who developed clinically significant CMV infection (CS-CMVi; CMV viremia requiring preemptive therapy or CMV disease) discontinued the study drug and began anti-CMV treatment. The primary endpoint was the proportion of patients with CS-CMVi through week 24 post-HCT; patients who discontinued the trial or with missing data were imputed as primary endpoint events. Between August 2013 and June 2015, 452 patients were randomized at a median of 15 days after HCT and received study drug. The proportion of patients who developed CS-CMVi or were imputed as having a primary endpoint event through week 24 was similar between brincidofovir-treated patients and placebo recipients (155 of 303 [51.2%] versus 78 of 149 [52.3%]; odds ratio, .95 [95% confidence interval, .64 to 1.41]; P = .805); fewer brincidofovir recipients developed CMV viremia through week 14 compared with placebo recipients (41.6%; P < .001). Serious adverse events were more frequent among brincidofovir recipients (57.1% versus 37.6%), driven by acute graft-versus-host disease (32.3% versus 6.0%) and diarrhea (6.9% versus 2.7%). Week 24 all-cause mortality was 15.5% among brincidofovir recipients and 10.1% among placebo recipients. Brincidofovir did not reduce CS-CMVi by week 24 post-HCT and was associated with gastrointestinal toxicity.

Definitions of Resistant and Refractory Cytomegalovirus Infection and Disease in Transplant Recipients for Use in Clinical Trials.

Despite advances in preventive strategies, cytomegalovirus (CMV) infection remains a major complication in solid organ and hematopoietic cell transplant recipients. CMV infection may fail to respond to commercially available antiviral therapies, with or without demonstrating genotypic mutation(s) known to be associated with resistance to these therapies. This lack of response has been termed "resistant/refractory CMV" and is a key focus of clinical trials of some investigational antiviral agents. To provide consistent criteria for future clinical trials and outcomes research, the CMV Resistance Working Group of the CMV Drug Development Forum (consisting of scientists, clinicians, regulatory officials, and industry representatives from the United States, Canada, and Europe) has undertaken establishing standardized consensus definitions of "resistant" and "refractory" CMV. These definitions have emerged from the Working Group's review of the available virologic and clinical literature and will be subject to reassessment and modification based on results of future studies.

Inactivated varicella zoster vaccine in autologous haemopoietic stem-cell transplant recipients: an international, multicentre, randomised, double-blind, placebo-controlled trial.

BACKGROUND: Recipients of autologous haemopoietic stem-cell transplants (auto-HSCT) have an increased risk of herpes zoster and herpes zoster-related complications. The aim of this study was to establish the efficacy and safety of an inactivated varicella zoster vaccine for the prevention of herpes zoster after auto-HSCT. METHODS: In this randomised, double-blind, placebo-controlled phase 3 trial, participants were recruited from 135 medical centres (ie, stem-cell transplant centres and hospitals) in North America, South America, Europe, and Asia. Patients were eligible if they were aged 18 years or older, scheduled to receive an auto-HSCT within 60 days of enrolment, and had a history of varicella infection or were seropositive for antibodies to varicella zoster virus, or both. Exclusion criteria included a history of herpes zoster within the previous year of enrolment, and intended antiviral prophylaxis for longer than 6 months after transplantation. Participants were randomly assigned according to a central randomisation schedule generated by the trial statistician, to receive either the inactivated-virus vaccine from one of three consistency lots, a high-antigen lot, or placebo, stratified by age (<50 vs ≥50 years) and intended duration of antiviral prophylaxis after transplantation (≤3 months vs >3 to ≤6 months). Participants, investigators, trial staff, and the funder's clinical and laboratory personnel were masked to group assignment. Participants were given four doses of inactivated vaccine or placebo, with the first dose 5-60 days before auto-HSCT, and the second, third, and fourth doses at about 30, 60, and 90 days after transplantation. The primary efficacy endpoint was the incidence of herpes zoster, confirmed by PCR or adjudication by a masked clinical committee, or both, assessed in all participants randomly assigned to the vaccine consistency lot group or placebo group who received at least one dose of vaccine and had auto-HSCT. Safety was assessed in all randomised participants who received at least one dose of vaccine and had follow-up data. A prespecified vaccine efficacy success criterion required the lower bound of the 95% CI be higher than 25% for the relative reduction of the hazard ratio of herpes zoster infection in participants given the vaccine from one of the consistency lots compared with those given placebo. This trial is registered on ClinicalTrials.gov (NCT01229267) and EudraCT (2010-020150-34). FINDINGS: Between Dec 7, 2010, and April 25, 2013, 560 participants were randomly assigned to the vaccine consistency lot group, 106 to the high-antigen lot group, and 564 to the placebo group. 249 (44%) of patients in the vaccine consistency lot group, 35 (33%) in the high-antigen lot group, and 220 (39%) in the placebo group discontinued before study end, mostly because of death or withdrawal. 51 participants were excluded from the primary efficacy endpoint analyses because they did not undergo auto-HSCT or were not vaccinated, or both (22 [4%] in the vaccine consistency lot group, and 29 [5%] in the placebo group). Mean follow-up for efficacy was 2·4 years (SD 1·3) in the vaccine consistency lot group and 2·3 years (SD 1·3) in the placebo group. 42 (8%) of 538 participants in the vaccine consistency lot group (32·9 per 1000 person-years) and 113 (21%) of 535 in the placebo group (91·9 per 1000 person-years) had a confirmed case of herpes zoster. The estimated vaccine efficacy was 63·8% (95% CI 48·4-74·6), meeting the pre-specified success criterion. For the combined vaccine groups versus the placebo group, the proportion of patients with serious adverse events (216 [33%] of 657 vs 181 [33%] of 554; risk difference 0·2%, 95% CI -5·1 to 5·5) and serious vaccine-related adverse events (five [1%] vs five [1%]; risk difference 0·1%, -1·4 to 1·1) were similar. Vaccine-related injection-site adverse events occurred more frequently in participants given vaccine than those given placebo (191 [29%] vs 36 [7%]; risk difference 22·6%, 95% CI 18·5-26·6; p<0·0001). INTERPRETATION: This study shows for the first time in a large phase 3 trial that early vaccination of auto-HSCT recipients during the peri-transplant period can be effective for the prevention of an opportunistic infection like herpes zoster and that the vaccine is well tolerated. FUNDING: Merck & Co., Inc.

Isavuconazole for treatment of invasive fungal diseases caused by more than one fungal species.

The optimal approach to treat invasive fungal disease (IFD) caused by more than one fungal species is unknown. We documented the efficacy and safety of isavuconazole for treatment of IFDs caused by more than one fungal species. VITAL was a single-arm, international, open-label study evaluating the efficacy and safety of isavuconazole (200 mg orally or intravenously every 8 hours for 48 hours, then once daily) for treatment of rare IFDs. The primary outcome was the overall response at Day 42; key secondary outcomes were overall responses at Day 84 and end of treatment (EOT), mortality at Days 42 and 84, and safety. This analysis includes patients with IFD caused by multiple fungal species. Fifteen patients were included in this analysis (including Aspergillus spp., n = 11; without Aspergillus spp., n = 4); median treatment duration was 97 days [range, 6-544] days). Overall treatment success was observed in 2/15 patients (13.3%) at Days 42 and 84, and 2/14 (14.3%) at EOT. All-cause mortality was 2/15 (13.3%) at Day 42 and 4/15 (26.7%) at Day 84. All patients had ≥1 treatment-emergent adverse event (TEAE); 12 patients (80.0%) had serious TEAEs; TEAEs led to discontinuation of isavuconazole in two patients (13.3%). Isavuconazole may be useful to treat some IFDs caused by multiple fungal species.

Isavuconazole for treatment of rare invasive fungal diseases.

Data regarding treatment of rare invasive fungal diseases (IFDs) are scarce. We documented the efficacy and safety of isavuconazole for treatment of uncommonly diagnosed IFDs. VITAL was a single-arm, international, open-label study evaluating the efficacy and safety of isavuconazole (200 mg orally or intravenously every 8 hours for 48 hours, then once daily). The primary outcome was overall response at Day 42; key secondary outcomes were overall responses at Day 84 and end of treatment (EOT), mortality at Days 42 and 84, and safety. This analysis includes patients with IFD caused by rare or unidentified pathogens. Twenty-six patients with IFDs caused by rare moulds (n = 17), non-Candida yeasts (n = 2), or unidentified moulds (n = 7) were enrolled (median treatment duration [range], 114.5 [1-496]) days. Overall treatment success was observed in 11/26 (42.3%), 10/26 (38.5%), and 15/26 (57.7%) patients at Days 42, 84, and EOT, respectively. All-cause mortality rates were 2/26 patients (7.7%) at Day 42 and 4/26 patients (15.4%) at Day 84; another two patients died after Day 84. All patients had ≥1 treatment-emergent adverse event (TEAE); 15 patients (57.7%) had serious TEAEs, and TEAEs led to discontinuation of isavuconazole in four patients (15.4%). Isavuconazole may be efficacious for treatment of a range of rare IFDs.