Pooled Microbiological Findings and Efficacy Outcomes by Pathogen in Adults With Community-Acquired Bacterial Pneumonia from the Lefamulin Evaluation Against Pneumonia (LEAP) 1 and LEAP 2 Phase 3 Trials of Lefamulin Versus Moxifloxacin

BACKGROUND

Lefamulin, a pleuromutilin antibiotic approved for community-acquired bacterial pneumonia (CABP), was evaluated for microbiological efficacy in a prespecified pooled analysis of LEAP 1 and 2 phase 3 clinical trial data in patients with CABP.

METHODS

In LEAP 1, adults (Pneumonia Outcomes Research Team [PORT] risk class III‒V) received intravenous (IV) lefamulin 150 mg every 12 hours (q12h; 5‒7 days) or moxifloxacin 400 mg every 24 hours (q24h; 7 days), with optional IV-to-oral switch. In LEAP 2, adults (PORT II‒IV) received oral lefamulin 600 mg q12h (5 days) or moxifloxacin 400 mg q24h (7 days). Primary outcomes were early clinical response (ECR) 96±24 hours after treatment start and investigator assessment of clinical response (IACR) 5‒10 days after last dose. Secondary outcomes included ECR and IACR in patients with a baseline CABP pathogen (detected via culture, urinary antigen test, serology, and/or real-time PCR).

RESULTS

Baseline CABP pathogens were detected in 709/1289 patients (55.0% [microbiological intent-to-treat population]). The most frequently identified pathogens in this population were Streptococcus pneumoniae (61.9% of patients) and Haemophilus influenzae (29.9%); 25.1% had atypical pathogens and 33.1% had polymicrobial infections. Pathogens were identified most frequently by PCR from sputum, followed by culture from respiratory specimens. In patients with baseline CABP pathogens, ECR rates were 89.3% (lefamulin) and 93.0% (moxifloxacin); IACR success rates were 83.2% and 86.7%, respectively. Results were consistent across CABP pathogens, including drug-resistant isolates and polymicrobial infections.

CONCLUSIONS

Lefamulin is a valuable IV and oral monotherapy option for empiric and directed CABP treatment in adults.

Oral 5-Day Lefamulin for Outpatient Management of Community-Acquired Bacterial Pneumonia: Post-hoc Analysis of the Lefamulin Evaluation Against Pneumonia (LEAP) 2 Trial

BACKGROUND

Safe and effective oral antibiotics are needed for outpatient management of moderate to severe community-acquired bacterial pneumonia (CABP).

OBJECTIVE

We describe a post-hoc analysis of adults with CABP managed as outpatients from the Lefamulin Evaluation Against Pneumonia (LEAP) 2 double-blind, noninferiority, phase 3 clinical trial.

METHODS

LEAP 2 compared the efficacy and safety of oral lefamulin 600 mg every 12 h (5 days) vs. oral moxifloxacin 400 mg every 24 h (7 days) in adults (inpatients and outpatients) with Pneumonia Outcomes Research Team (PORT) risk classes II‒IV.

RESULTS

Overall, 41% (151 of 368) of patients receiving lefamulin and 43% (159 of 368) of patients receiving moxifloxacin started treatment as outpatients-44% and 40%, respectively, were PORT risk class III/IV, and 21% in both groups had CURB-65 scores of 2‒3. Early clinical response (at 96 ± 24 h) and investigator assessment of clinical response success rates at test of cure (5‒10 days after last study drug dose) were high and similar in both groups among all (lefamulin, 91% vs. moxifloxacin, 89‒90%), PORT risk class III/IV (89‒91% vs. 88‒91%), and CURB-65 score 2‒3 (87‒90% vs. 82‒88%) outpatients. Few outpatients (lefamulin, 2.6%; moxifloxacin, 2.5%) discontinued the study drug because of treatment-emergent adverse events (TEAEs). No outpatient in the lefamulin group was hospitalized for a TEAE, compared with 5 patients (3%), including two deaths, in the moxifloxacin group.

CONCLUSIONS

These data suggest that 5 days of oral lefamulin can be given in lieu of fluoroquinolones for outpatient treatment of adults with CABP and PORT risk class III/IV or CURB-65 scores of 2‒3.

A Multicenter Evaluation of the US Prevalence and Regional Variation in Macrolide-Resistant S. pneumoniae in Ambulatory and Hospitalized Adult Patients in the United States

Macrolide resistance was found in 39.5% of 3626 nonduplicate Streptococcus pneumoniae isolates from adult ambulatory and inpatient settings at 329 US hospitals (2018–2019). Macrolide resistance was significantly higher for respiratory vs blood isolates and ambulatory vs inpatient settings. Despite geographic variation, S. pneumoniae macrolide resistance was >25% in most regions.

Health-Related Quality of Life as Measured by the 12-Item Short-Form Survey Among Adults With Community-Acquired Bacterial Pneumonia who Received Either Lefamulin or Moxifloxacin in 2 Phase III Randomized, Double-Blind, Double-Dummy Clinical Trials

Background

Interest in patient-reported outcomes (PROs) as part of benefit–risk assessment for new drug approvals is increasing. Lefamulin is the first intravenous (IV) and oral pleuromutilin antibiotic for treatment of adults with community-acquired bacterial pneumonia (CABP). Assessment of health-related quality of life (HRQoL) was prospectively incorporated in its CABP trials (Lefamulin Evaluation Against Pneumonia [LEAP] 1 and 2) via the 12-Item Short-Form Survey (SF-12), a widely used PRO that measures general health status in 8 domains.

Methods

HRQoL was evaluated by SF-12 at baseline and test of cure (TOC; 5–10 days after the last study drug dose) in patients who received lefamulin or moxifloxacin in LEAP 1 (IV/oral treatment) and LEAP 2 (oral-only treatment). SF-12 outcomes included the 8 domains, physical component and mental component summary scores, and the Short-Form Six-Dimension health utility score.

Results

Analysis included 1215 patients (lefamulin: n = 607; moxifloxacin: n = 608). At baseline, all mean SF-12 scores in both treatment groups were well below the United States reference mean. Clinically meaningful and significant improvements from baseline to TOC were observed in all SF-12 scores. No significant differences in mean score improvements from baseline to TOC between treatment groups were observed. SF-12 score improvements at TOC across predefined subgroups were comparable between treatment groups.

Conclusions

Results indicate that adults with CABP experienced comparable HRQoL improvements with lefamulin relative to moxifloxacin, and treatment with either agent resulted in returns to population norm HRQoL levels. These data suggest that lefamulin is a potential alternative to moxifloxacin for treatment of adults with CABP.

Post Hoc Assessment of Time to Clinical Response Among Adults Hospitalized with Community-Acquired Bacterial Pneumonia Who Received Either Lefamulin or Moxifloxacin in 2 Phase III Randomized, Double-Blind, Double-Dummy Clinical Trials

Time to clinical response, a proxy for hospital "discharge readiness," was compared between CABP inpatients who received lefamulin or moxifloxacin in the Lefamulin Evaluation Against Pneumonia (LEAP) trials. The analysis included 926 inpatients. A short and comparable median time to clinical response (4 days) was observed in both treatment groups.

The 1-year economic burden of community-acquired pneumonia (CAP) initially managed in the outpatient setting in the USA

Aim: To assess the annual economic burden of community-acquired pneumonia (CAP) initially managed in the outpatient setting. Patients & methods: Patients with an outpatient diagnosis of CAP between January 2012 and December 2016 were identified from the IQVIA (Danbury, CT & Durham, NC, USA) Real-World Data Adjudicated Claims – US Database. All-cause and CAP-related healthcare resource utilization and costs were assessed over the 1-year follow-up. Generalized linear model examined adjusted total cost. Results: Among 256,916 patients with outpatient CAP, a tenth (10.6%) had ≥1 hospitalization and, of these, 18.7% had ≥1 CAP-related hospitalization. The mean total cost per patient was US$14,372; 10.9% was CAP-related and 26.1% was due to inpatient care. The adjusted mean total all-cause cost was US$13,788. Conclusion: Patients with outpatient CAP incurred a substantial annual economic burden.

The annual economic burden among patients hospitalized for community-acquired pneumonia (CAP): a retrospective US cohort study

Objective: To assess the 1-year economic burden among patients hospitalized for community-acquired pneumonia (CAP) in the US.Methods: Adult patients hospitalized for CAP between 1/2012 and 12/2016 were identified from the IQVIA hospital charge data master (CDM) linked to the IQVIA Real-World Data Adjudicated Claims - US Database (date of admission = index date). Patients had continuous enrollment 180-days pre- and 360-days post-index, and empiric antimicrobial treatment (monotherapy [EM] or combination therapy [EC]) and chest x-ray on the index date or day after. All-cause and CAP-related healthcare resource utilization and cost were assessed over the 1-year follow-up. Generalized linear models (GLM) examined adjusted total cost.Results: The cohort comprised 1624 patients hospitalized for CAP (mean age 50.3; 52.8% female). The majority (78.2%) initiated EC, most frequently with beta-lactams + macrolides (30.4%). The index hospitalization was associated with a mean length of stay (LOS) of 5.7 days and mean cost of $17,736; 22.7% had a transfer to the intensive care unit (ICU). All-cause readmission rates at 30- and 180-days were 8.8% and 20.1%, respectively. Mean annual all-cause total cost was $61,928; one-third (33.8%, $20,954) was related to CAP. The primary cost driver was inpatient care, which accounted for more than half (56.0%) of total all-cause cost and 94.3% of total CAP-related cost. Mean total inpatient cost was significantly higher among EC versus EM patients ($37,106 versus $25,999, p = .0399). Adjusted mean total all-cause cost was $55,391.Conclusions: Patients hospitalized for CAP incurred a significant annual economic burden, driven substantially by the high cost of hospitalizations.

Oral Lefamulin vs Moxifloxacin for Early Clinical Response Among Adults With Community-Acquired Bacterial Pneumonia: The LEAP 2 Randomized Clinical Trial

IMPORTANCE

New antibacterials are needed to treat community-acquired bacterial pneumonia (CABP) because of growing antibacterial resistance and safety concerns with standard care.

OBJECTIVE

To evaluate the efficacy and adverse events of a 5-day oral lefamulin regimen in patients with CABP.

DESIGN, SETTING, AND PARTICIPANTS

A phase 3, noninferiority randomized clinical trial conducted at 99 sites in 19 countries that included adults aged 18 years or older with a Pneumonia Outcomes Research Team (PORT) risk class of II, III, or IV; radiographically documented pneumonia; acute illness; 3 or more CABP symptoms; and 2 or more vital sign abnormalities. The first patient visit was on August 30, 2016, and patients were followed up for 30 days; the final follow-up visit was on January 2, 2018.

INTERVENTIONS

Patients were randomized 1:1 to receive oral lefamulin (600 mg every 12 hours for 5 days; n = 370) or moxifloxacin (400 mg every 24 hours for 7 days; n = 368).

MAIN OUTCOMES AND MEASURES

The US Food and Drug Administration (FDA) primary end point was early clinical response at 96 hours (within a 24-hour window) after the first dose of either study drug in the intent-to-treat (ITT) population (all randomized patients). Responders were defined as alive, showing improvement in 2 or more of the 4 CABP symptoms, having no worsening of any CABP symptoms, and not receiving any nonstudy antibacterial drug for current CABP episode. The European Medicines Agency coprimary end points (FDA secondary end points) were investigator assessment of clinical response at test of cure (5-10 days after last dose) in the modified ITT population and in the clinically evaluable population. The noninferiority margin was 10% for early clinical response and investigator assessment of clinical response.

RESULTS

Among 738 randomized patients (mean age, 57.5 years; 351 women [47.6%]; 360 had a PORT risk class of III or IV [48.8%]), 707 (95.8%) completed the trial. Early clinical response rates were 90.8% with lefamulin and 90.8% with moxifloxacin (difference, 0.1% [1-sided 97.5% CI, -4.4% to ∞]). Rates of investigator assessment of clinical response success were 87.5% with lefamulin and 89.1% with moxifloxacin in the modified ITT population (difference, -1.6% [1-sided 97.5% CI, -6.3% to ∞]) and 89.7% and 93.6%, respectively, in the clinically evaluable population (difference, -3.9% [1-sided 97.5% CI, -8.2% to ∞]) at test of cure. The most frequently reported treatment-emergent adverse events were gastrointestinal (diarrhea: 45/368 [12.2%] in lefamulin group and 4/368 [1.1%] in moxifloxacin group; nausea: 19/368 [5.2%] in lefamulin group and 7/368 [1.9%] in moxifloxacin group).

CONCLUSIONS AND RELEVANCE

Among patients with CABP, 5-day oral lefamulin was noninferior to 7-day oral moxifloxacin with respect to early clinical response at 96 hours after first dose.

TRIAL REGISTRATIONS

ClinicalTrials.gov Identifier: NCT02813694; European Clinical Trials Identifier: 2015-004782-92.

663. Efficacy and Safety of Lefamulin (LEF) vs. Moxifloxacin (MOX) for Legionella pneumophila (LP) in Patients with Community-Acquired Bacterial Pneumonia (CABP): Pooled Results From the Lefamulin Evaluation Against Pneumonia (LEAP) 1 and LEAP 2 Phase 3 Clinical Trials

Background

LP is associated with severe CABP, rapid onset, and high morbidity/mortality. Poor outcomes in CABP have been linked to receiving inappropriate empiric therapy or delayed treatment (tx). LEF, a novel IV/oral pleuromutilin, demonstrated efficacy/safety in noninferiority studies (LEAP 1/2) vs. MOX in adults with CABP. We report efficacy/safety of LEF in patients with LP based on a pooled analyses of LEAP 1/2 data.

Methods

In LEAP 1, PORT III–V patients received LEF 150 mg IV q12h for 5–7 days or MOX 400 mg IV q24h for 7 days, with optional IV-to-oral switch (600 mg LEF q12h or 400 mg MOX q24h). In LEAP 2, PORT II–IV patients received oral LEF for 5 days or oral MOX for 7 days. Both studies assessed early clinical response (ECR) at 96 ± 24 hours after first dose in the intent-to-treat (ITT; all randomized patients) population and investigator assessment of clinical response (IACR) at test-of-cure (TOC; 5–10 days after last dose) in the modified ITT (received ≥1 dose) and clinically evaluable (met predefined evaluability criteria) populations. LP was identified from baseline (BL) samples by culture, serology (IgG, Zeus L. pneumophila group 1–6 indirect fluorescent antibody assay), urine antigen testing (BinaxNOW), and real-time PCR (positive for ssrA). Efficacy analyses herein were done in the microbiological ITT (microITT, treated patients with BL CABP-causing pathogen), microITT-2 (no PCR), and microbiologically evaluable populations; safety analyses included all randomized/treated patients.

Results

Of 65 pooled microITT patients, median age was 60 y, 66% were male, 51% had a normal renal function, and 54%/25% were PORT III/IV. LP was identified in 9.3% (34/364) of LEF patients (7 [20.6%]/19 [55.9%]/8 [23.5%] PORT II/III/IV) and in 9.0% (31/345) of MOX patients (7 [22.6%]/16 [51.6%]/8 [25.8%] PORT II/III/IV), primarily by urine antigen or serology (table). Patients with LP in both tx groups achieved high and similar responses across all endpoints (Figures 1 and 2). In both tx groups, TEAE rates were low and comparable (~32%) and most were mild to moderate; 5 patients (3 LEF; 2 MOX) had treatment-emergent SAEs, all unrelated to tx. No patients died due to TEAEs; no LEF patients and 2 MOX patients discontinued tx due to TEAEs.

Conclusion

LEF appears to be as safe and effective as MOX in treating patients with LP, including when given as short-course (5 days) oral therapy.

Disclosures

All authors: No reported disclosures.

1485. Trends in Important-Resistant Gram-Negative (GN) and Gram-Positive (GP) Urine Bacterial Pathogens in Hospitalized Patients in the United States: A Multicenter Evaluation from 2013 to 2018

Background

The US CDC has identified a number of antibiotic-resistant (AR) bacteria as urgent or serious public health threats. This study sought to quantify the prevalence and incidence of extended-spectrum β-lactamase (ESBL) Enterobacteriaceae (ENT), Carbapenem-resistant ENT (CRE), P. aeruginosa (Carb NS-PsA), vancomycin-resistant enterococci (VRE), and methicillin-resistant S. aureus (MRSA) in the urine of adult hospitalized patients.

Methods

All hospitalized adult patients with a positive urine culture (first urine isolate of a species per 30-day period) were evaluated from over 400 US hospitals (2013–2018; BD Insights Research Database, Becton, Dickinson and Company). The following five groups of AR bacteria were examined: (1) ESBL ENT if ESBL-positive per commercial panels or intermediate/resistant (non-susceptible [NS]) to a third-generation cephalosporin; (2) CRE ENT if NS to imipenem (IPM), meropenem (MEM), doripenem (DOR) or ertapenem; (3) Carb-NS PsA if NS to IPM, MEM or DOR; (4) VRE if resistant to vancomycin; and (5) MRSA as resistant to methicillin/oxacillin. For each AR grouping, % NS and rates of NS per 100 admissions were calculated and trends were examined using Logistic regression and Poisson models.

Results

Across the 6-year study period, there were 24,558,856 admissions, accounting for 2,285,971 non-duplicate urine isolates; 1,016,642 were ENT, 87,450 were PSA, 203,231 were enterococci, and 41,979 were S. aureus. The % of NS for ESBL, CRE ENT, Carb-NS PsA, VRE, and MRSA were 12%, 0.9%, 13%, 19%, and 55%, respectively. The % of NS for ESBL increased from 2013 to 2018 (P < 0.001) whereas % NS for PsA and % MRSA decreased during the same time period (P < 0.001) (Figure 1). The rates of NS per 100 admissions for ESBL, CRE ENT, Carb-NS PsA, VRE, and MRSA were 0.44, 0.04, 0.05, 0.16, and 0.09, respectively. The annual NS rates per 100 admission trends for ESBL and CRE ENT were increasing (all P < 0.0001) while the trends for Carb-NS PsA, VRE, and MRSA were decreasing (all P < 0.0001).

Conclusion

While the percent of ESBL, CRE ENT, Carb-NS PsA, VRE, and MRSA have remained relatively constant over the past 6 years, there has been a notable increase in the rates of ESBL and CRE ENT per 100 admissions among adult hospitalized patients with positive urine cultures.

Disclosures

All authors: No reported disclosures.

676. Health-Related Quality of Life (HRQoL) as Measured by the 12-Item Medical Outcomes Study Short-Form (SF-12) Among Adults With Community-Acquired Bacterial Pneumonia (CABP) Who Received Either Lefamulin (LEF) or Moxifloxacin (MOX) in Two Phase 3 Randomized, Double-Blind, Double-Dummy Clinical Trials (LEAP 1 and 2)

Background

Interest in patient health experience as part of a benefit–risk assessment for new drug approvals is increasing. Patient-centeredness, a key metric in the 2010 Affordable Care Act, is also a growing area of focus in healthcare. LEF, a new antibiotic in development for treating adults with CABP, was noninferior to MOX based on clinical response endpoints in LEAP 1 and 2. HRQoL was prospectively incorporated and evaluated in both studies via SF-12, a well-known survey that measures general health status in 8 domains (physical function, role limitations due to physical problems, bodily pain, general health, vitality, social function, role limitations due to emotional problems, and mental health).

Methods

An exploratory analysis evaluated HRQoL in patients who received LEF or MOX in LEAP 1 (IV-PO treatment) and LEAP 2 (PO-only treatment). SF-12 was measured at baseline (BL) and test-of-cure (TOC; 5–10 days after last study drug dose). SF-12 outcomes assessed included the 8 domains, physical component summary (PCS), and mental component summary (MCS) scores. SF-12 scores were normalized to the 2009 US population reference mean (SD) of 50 (10). A 3-point change on any scale represents a clinically meaningful difference.

Results

Analysis included 1,215 patients (LEF n = 607; MOX n = 608). At BL, all mean SF-12 scores in both treatment groups were well below the US reference mean, indicating a low HRQoL level, consistent with the acute illness of the study population (figure). Clinically meaningful and significant improvements from BL to TOC were observed in all domain, PCS, and MCS scores in both groups. Mean scores were close to the reference mean, indicating an average HRQoL level. No significant differences in mean score improvements from BL to TOC were seen for LEF vs. MOX. SF-12 score improvements at TOC across predefined subgroups (age, sex, number of comorbidities, study, and PORT risk class) were comparable between treatment groups.

Conclusion

Our data indicate that adults with CABP experienced HRQoL improvements with LEF that were comparable with MOX, and treatment with either agent resulted in return to normal HRQoL. When combined with overall study results, these data suggest LEF as a potential alternative to MOX for treatment of adults with CABP.

Disclosures

All authors: No reported disclosures.

717. Lefamulin (LEF) vs. Moxifloxacin (MOX) in Patients With Community-Acquired Bacterial Pneumonia (CABP) at Risk for Poor Efficacy or Safety Outcomes: Pooled Subgroup Analyses From the Lefamulin Evaluation Against Pneumonia (LEAP) 1 and LEAP 2 Phase 3 Noninferiority Clinical Trials

Background

In the United States, CABP is the second most common cause of hospitalization and a leading cause of infectious death. Patients with chronic obstructive pulmonary disease (COPD)/asthma or diabetes are at risk for CABP and associated mortality. Similarly, patients with underlying cardiac or liver disease are at risk for potential cardiac or liver toxicities, respectively, associated with CABP antimicrobials, and patients aged ≥65 years are at risk for both efficacy/safety concerns. We report pooled efficacy/safety outcomes in at-risk subgroups from the LEAP 1 and 2 phase 3 trials.

Methods

In LEAP 1, patients with CABP (PORT III–V) received IV LEF 150 mg q12h for 5–7 days or MOX 400mg q24h for 7 days, with optional IV-to-oral switch (600 mg LEF q12h or 400 mg MOX q24h). In LEAP 2, patients with CABP (PORT II–IV) received oral LEF 600 mg q12h for 5 days or MOX 400 mg q24h for 7 days. Both studies assessed early clinical response (ECR; 96 ± 24 hours after first dose) in the intent-to-treat (ITT; all randomized patients) population (FDA primary endpoint) and investigator assessment of clinical response (IACR) at test-of-cure (TOC; 5–10 days after last dose) in the modified ITT (≥1 study drug dose) and clinically evaluable (met predefined evaluability criteria) populations (EMA coprimary endpoints). Pooled analyses used a 10% noninferiority margin. Safety was assessed in all randomized and treated patients.

Results

1289 ITT patients were randomized to LEF (n = 646) or MOX (n = 643); of whom, 297 (23.0%) were aged 65–74 years and 220 (17.1%) were ≥75 years; 232 patients (18.0%) had COPD/asthma and 168 (13.0%) had diabetes mellitus (DM). At baseline, 501 patients (38.9%) had history of hypertension, 73 (5.7%) had history of arrhythmia, and 263 (20.4%) had transaminitis. The figure shows efficacy by age and in COPD/asthma and DM patients. Treatment-emergent adverse events, electrocardiogram assessments, and laboratory results in patients at risk for cardiac and hepatic safety concerns are shown in Tables 1 and 2.

Conclusion

In pooled analyses of LEAP 1 and 2, LEF efficacy was high and similar to MOX in patients at risk of efficacy concerns and LEF showed a safety profile similar to that of MOX in patients at risk of safety concerns. LEF is a promising new option for IV/oral monotherapy of CABP in patients at risk of poor outcomes due to CABP or to antimicrobial therapy for CABP.

Disclosures

All authors: No reported disclosures.

2233. Efficacy and Symptom Resolution by Visit in Adults With Community-Acquired Bacterial Pneumonia (CABP) Treated With Lefamulin (LEF) or Moxifloxacin (MOX): Pooled Analysis of Lefamulin Evaluation Against Pneumonia (LEAP) 1 and LEAP 2 Study Results

Background

Efficacy and safety of LEF were shown in 2 noninferiority trials (LEAP 1/2) vs. MOX in adults with CABP. We assessed the efficacy of LEF by visit based on a pooled analyses of LEAP 1/2 data.

Methods

In LEAP 1, PORT III–V patients (patients) received LEF 150 mg IV q12h for 5–7 days or MOX 400 mg IV q24h for 7 days, with optional IV-to-oral switch (600 mg LEF q12h or 400 mg MOX q24h). In LEAP 2, PORT II–IV patients received oral LEF 600 mg q12h for 5 days or oral MOX 400 mg q24h for 7 days. Criteria for defining the FDA primary endpoint of early clinical response (ECR) at 96 ± 24 hours after first dose were applied to each visit through late follow-up (LFU; days 27–34) in the intent-to-treat (ITT; all randomized patients) population. Investigator assessment of clinical response (IACR) was examined at end of treatment (EOT; within 2 days after last dose), test-of-cure (TOC; 5–10 days after last dose; EMA primary endpoint), and LFU in the modified ITT (mITT; received ≥1 dose of study drug) and clinically evaluable (CE; met predefined evaluability criteria) populations. Results are presented by visit for pooled LEAP 1/2 data.

Results

1289 ITT patients were randomized (LEF, n = 646; MOX, n = 643). Most patients in both groups achieved ECR at Day 3, with further increases through Day 7 and sustained efficacy through LFU (Fig 1). In mITT patients, IACR success rates at EOT/TOC/LFU were 87.1/85.0/83.2% with LEF and 88.1/87.1/86.1% with MOX; results were consistent in CE patients. The proportions of ITT patients with resolution of all baseline signs/symptoms of CABP increased similarly by visit in both treatment groups (Fig 2). Most patients did not achieve complete sign/symptom resolution until TOC, with fever generally being the first and cough the last to resolve. There was no apparent relationship between ECR and age, gender, renal status, SIRS, PORT, prior antibiotic use, baseline pathogens, typical/atypical pathogens, or mono/polymicrobial pathogens. The high percentage of patients at LFU with baseline symptom resolution suggests that symptom resolution was sustained.

Conclusion

In this pooled analysis, efficacy results were similar by visit in the LEF and MOX groups, with high ECR rates maintained through LFU. LEF will provide a potential new effective systemic monotherapy alternative to fluoroquinolones for the empiric treatment of CABP.

Disclosures

All authors: No reported disclosures.

699. Hepatobiliary Safety in Adults With Community-Acquired Bacterial Pneumonia (CABP) Treated With Lefamulin (LEF) or Moxifloxacin (MOX): Pooled Analysis of Lefamulin Evaluation Against Pneumonia (LEAP) 1 and LEAP 2 Study Results

Background

LEF efficacy and safety were shown in 2 noninferiority trials (LEAP 1/2) vs. MOX in adults with CABP. We assessed the hepatobiliary safety of LEF based on pooled analyses of LEAP 1/2 data.

Methods

In LEAP 1, PORT III–V patients received LEF 150 mg IV q12h for 5–7 days or MOX 400 mg IV q24h for 7 days, with optional IV-to-oral switch (600 mg LEF q12h or 400 mg MOX q24h). In LEAP 2, PORT II–IV patients received oral LEF 600 mg q12h for 5 days or oral MOX 400mg q24h for 7 days. Exclusion criteria included infection with HBV/HCV, acute hepatitis, cirrhosis, AST or ALT >5xULN, total bilirubin >3xULN (unless Gilbert’s disease), AST or ALT >3xULN and total bilirubin >2xULN, and manifestation of end-stage liver disease. Hepatic safety was assessed from baseline (BL) and multiple post-BL blood samples using a central laboratory, TEAEs, and expert consultant adjudication. Pooled analyses included all randomized/treated patients (safety population).

Results

Of 1282 randomized/treated patients, 1251 had BL and post-BL hepatobiliary data (table). Post-BL distribution of ALT/AST was generally similar for both groups, although ALT >AST in the absence of muscle injury or alcohol use. Overall, rates of patients experiencing an increase in ALT/AST >3xULN, ALP >2xULN, or total bilirubin >1.5xULN were low (table). Patients with elevated vs. normal BL transaminases (TAs) were more likely to have post-BL elevations >3xULN, but the vast majority remained <5xULN. Among patients with ALT >5xULN, peak increases were generally seen in the first week after the first LEF dose and declined to within/near normal levels by late follow-up (day 28); for MOX, time to peak ALT was less consistent (figure). No LEF pt and 1 MOX pt met laboratory criteria for Hy’s Law. Elevations in TAs were reversible, with no evidence of chronic injury. The LEF injury pattern was predominantly hepatocellular (50.0%)/mixed (40.0%), with no apparent gender, age, or ethnic predominance. TEAEs in the hepatobiliary disorders system organ class were reported in 6 (0.9%) LEF patients and 6 (0.9%) MOX patients, with similar levels seen in patients with elevated BL TAs. There were no symptomatic patients, severe disease, or evidence of hypersensitivity.

Conclusion

Low incidences of hepatobiliary parameter elevations and TEAEs were observed, with no apparent differences between LEF and MOX.

Disclosures

All authors: No reported disclosures.

2245. Oral 5-Day Lefamulin for Outpatient Management of Pneumonia Outcomes Research Team (PORT) Risk Class III/IV Community-Acquired Bacterial Pneumonia (CABP): Post Hoc Analysis of the Lefamulin Evaluation Against Pneumonia (LEAP) 2 Phase 3 Study

Background

Site-of-care decisions (e.g., admission vs. outpatient) in CABP management can be challenging for healthcare providers. Here we describe a post hoc analysis of adults with CABP managed as outpatients in the LEAP 2 double-blind, noninferiority, Phase 3 trial.

Methods

LEAP 2 compared the efficacy and safety of oral lefamulin (LEF) 600 mg every 12 hours for 5 days vs. oral moxifloxacin (MOX) 400 mg every 24 hours for 7 days in adults with PORT Risk Class II-IV. Descriptive statistics were generated to characterize demographics, baseline characteristics, efficacy, and safety outcomes in the subpopulation of outpatients in LEAP 2.

Results

Overall, 42% (310/736) of patients started treatment as outpatients (41% [151/368] LEF and 43% [159/368] MOX). Age, gender, and BMI were generally similar in both treatment groups. 44% (66/151) LEF and 40% (64/159) MOX outpatients had PORT Risk Class III or IV, and 21% in both groups (31/151 LEF and 34/159 MOX) had CURB-65 score 2 or 3. Comorbidities included smoking history (43% LEF vs. 34% MOX), hypertension (26% vs. 30%), COPD/asthma (14% vs. 18%), and diabetes mellitus (7% vs. 11%). Early clinical response (ECR) responder rates and investigator’s assessment of clinical response (IACR) success rates at the test of cure (TOC) visit were high and similar in both groups among all, PORT Risk Class III/IV, and CURB-65 score 2 or 3 outpatients (Table 1). In the PORT Risk Class III/IV subset, 86% LEF vs. 80% MOX patients were both an ECR responder and IACR success at TOC. In the CURB-65 score 2 or 3 subset, 87% LEF vs. 74% MOX patients were both an ECR responder and IACR success at TOC. Treatment-emergent adverse event (TEAE) rates were similar in both groups (Table 2). Consistent with overall study results, the difference between groups in related TEAEs was driven by gastrointestinal disorders (20% LEF vs. 5% MOX), specifically diarrhea (15% vs. 1%). Rates of TEAEs leading to discontinuation were low and similar in both groups. No LEF outpatient had an SAE or was admitted during the study, compared with 5 (3%) SAEs, including 2 deaths, in the MOX group.

Conclusion

These study data suggest that PORT Risk Class III or IV patients can be effectively managed as outpatients with 5 days of oral LEF as an alternative to fluoroquinolones for the treatment of CABP.

Disclosures

All authors: No reported disclosures.

1440. Prevalence and Regional Variation of in ESBLs and CRE Enterobacteriaceae (ENT) among Adult, Hospitalized Patients with ENT on a Urine Culture: A Multicenter Evaluation

Background

Despite increased public health awareness of ESBLs and CRE, limited data exist regarding the true frequency of these resistant bacteria in urine cultures collected from adult patients in US hospitals. This study sought to quantify the prevalence and rates of ESBLs and CRE from urine cultures in adult hospitalized patients with ENT.

Methods

All hospitalized adults with a urine culture (first urine isolate of a species per 30-day period) from 377 hospitals in 2018 were evaluated (BD Insights Research Database, Becton, Dickinson & Company). ESBL was defined as an ENT that was ESBL-positive per commercial panels or intermediate or resistant (non-susceptible, [NS]) to a third-generation cephalosporin; CRE was defined as an ENT that was NS to imipenem, meropenem, doripenem or ertapenem. Urine isolates were classified as community-onset (CO: < 3 days of an inpatient admission and no previous admission within 14 days) or hospital-onset (HO: ≥ 3 days post-admission or within 14 days of discharge) period. Prevalence and rates per 100 admissions were calculated overall, by onset location (CO vs. HO), and by US Department of Health and Human Services (HHS) geographic region.

Results

In 2018, there were 193,476 non-duplicate ENT urine isolates across 4,623,333 admissions; 63.6% were E. coli (EC), 19.5% were K. pneumoniae/oxytoca (KPO), and 8.7% were P. mirabilis (PM). Overall, 12.6% were ESBL and 0.9% were CRE. Rate per 100 admissions was 0.484 and 0.037 for ESBL and CRE, respectively. Among CO, 11.8% were ESBLs and ESBL rates per 100 admissions were 0.358; 0.7% were CRE and CRE rates per 100 admissions was 0.024. Among HO, 15.7% were ESBLs and ESBL rates per 100 admissions was 0.126; 1.5% were CRE and CRE rates per 100 admissions was 0.013. Regional differences in both ESBL and CRE ENT were noted (table).

Conclusion

The prevalence of ESBLs/CRE among adult hospitalized patients with ENT in a urine culture was 13% and 1%, respectively. The % ESBL/CRE was higher among patients HO urine isolates whereas ESBL/CRE rates per 100 admissions were higher among patients with CO urine isolates. Considerable geographic variations were observed. Region and site of onset differences in ESBL/CRE epidemiology should be considered when making empiric antibiotic treatment decisions.

Disclosures

All authors: No reported disclosures.

720. Efficacy of Fosfomycin for Injection (FOS) vs. Piperacillin–Tazobactam (PIP-TAZ) in Adults with Complicated Urinary Tract Infection (cUTI) and Acute Pyelonephritis (AP): ZEUS Study Outcomes in Patients With Reduced Study Drug Susceptibility

Background

FOS is being pursued for US registration in cUTI/AP. Safety and efficacy of FOS vs. PIP-TAZ were demonstrated in the noninferiority ZEUS trial in hospitalized patients with cUTI/AP. Although FOS resistance has been observed in several in vitro studies, resistance rates in clinical settings have remained relatively stable despite >40 years of clinical use of FOS outside of the United States. Here we report outcomes in patients who developed reduced susceptibility to study drug (FOS or PIP-TAZ) after enrollment in ZEUS.

Methods

Patients received IV FOS 6g q8h or PIP-TAZ 4.5g q8h for 7 days (no oral switch allowed). The primary endpoint was overall success (clinical cure + microbiologic eradication) in microbiologic modified intent-to-treat (m-MITT) population at test-of-cure (TOC; Day 19–21). Reduced susceptibility to FOS or PIP-TAZ was defined as a ≥4-fold increase from baseline in minimum inhibitory concentration (MIC) at Day 5, end of treatment (EOT; Day 7–8), TOC, or late follow-up (LFU; Day 26 ± 2). Microbiologic eradication/persistence of baseline and postbaseline pathogens was confirmed post hoc by pulsed-field gel electrophoresis (PFGE).

Results

In all m-MITT patients, overall success/clinical cure/microbiologic eradication rates (with PFGE) at TOC were 69.0/90.8/70.7% (FOS) and 57.3/91.6/60.1% (PIP-TAZ). Reduced study drug susceptibility was identified in 7/184 (3.8%) FOS and 8/178 (4.5%) PIP-TAZ patients; all had monomicrobial infections (Table 1). Of these patients, almost all were aged ≥50 years (93%), male (73%), white (100%), and had a screening diagnosis of cUTI (93%). At TOC, 7/7 FOS patients and 7/8 PIP-TAZ patients had microbiologic persistence but all patients were clinical cures; these responses were all sustained through LFU (Table 1).

Conclusion

In the ZEUS study, few patients had urine isolates with reduced postbaseline susceptibility to either FOS or PIP-TAZ. No trend was observed in isolate species associated with decreased susceptibility to FOS or PIP-TAZ, including various Enterobacteriaceae species and Pseudomonas aeruginosa. Despite microbiologic persistence at TOC in a small number of patients, all of these patients were clinical cures at TOC and sustained cures at LFU.

Disclosures

All authors: No reported disclosures.

664. Efficacy in Adults With Moderate to Severe Community-Acquired Bacterial Pneumonia (CABP) and Pneumonia Outcomes Research Team (PORT) Risk Class III to V: Results of a Pooled Analysis of Lefamulin Evaluation Against Pneumonia (LEAP) 1 and LEAP 2 Study Outcomes

Background

CABP, the second most common cause of hospitalization in the US, has prognoses ranging from rapid resolution to death, the likelihood of which can be estimated via PORT pneumonia severity index. Patients with PORT scores ≤III have predicted mortality rates <3% and may be managed as outpatients; those with scores of IV/V are often hospitalized, owing to higher predicted mortality rates (8%–31%). Lefamulin (LEF), a novel systemic antibiotic, was noninferior to moxifloxacin (MOX) for treatment of adults with CABP in 2 phase 3 trials (LEAP 1 and 2). We report the results of pooled analyses of LEAP 1/2 data in patients with PORT III and IV/V scores.

Methods

In LEAP 1, patients (PORT III–V) received IV LEF 150 mg for 5–7 d or MOX 400 mg for 7 d, with optional IV-to-oral switch. In LEAP 2, patients (PORT II–IV) received oral LEF 600 mg for 5 d or MOX 400 mg for 7 d. In both studies, randomization was stratified by PORT score. The studies assessed early clinical response (ECR; 96±24 h after first dose) in the intent-to-treat (ITT; all randomized patients) population (FDA primary endpoint) and investigator assessment of clinical response (IACR) success at test of cure (5–10 d after last dose) in the modified ITT (received ≥1 dose) and clinically evaluable (met predefined evaluability criteria) populations (EMA coprimary endpoints).

Results

Over 50% of patients (52.8% LEF; 51.9% MOX) were PORT III and >18% (18.7% LEF; 18.2% MOX) were PORT IV/V, reflective of the CABP population. As expected, PORT IV/V patients were older and more likely to have comorbidities (eg, moderate/severe renal impairment) vs. PORT III patients (Table 1). ECR and IACR response rates were high and similar for LEF and MOX in PORT III (Figure 1) and PORT IV/V (Figure 2) patients, with slightly higher rates in PORT III vs. PORT IV/V patients. LEF and MOX had similar safety profiles, with more adverse events overall in PORT IV/V vs. PORT III patients (Table 2). Mortality rates were low, with higher rates in PORT IV/V (4.2% LEF; 5.2% MOX) vs. PORT III (1.5% LEF; 0.6% MOX) patients.

Conclusion

ECR and IACR rates with LEF were high and similar to MOX in patients who are candidates for outpatient (PORT III) and inpatient (PORT IV/V) treatment; LEF may be an alternative oral and IV monotherapy option for empiric CABP treatment in both populations.

Disclosures

All authors: No reported disclosures.

684. Cardiac Safety in Adults with Community-Acquired Bacterial Pneumonia (CABP) Treated with Lefamulin (LEF) or Moxifloxacin (MOX): Analysis of Lefamulin Evaluation Against Pneumonia (LEAP) 1 and LEAP 2 Study Results

Background

Preclinical data suggest potential effects of LEF on cardiac interval parameters. We therefore assessed LEF cardiac safety from the LEAP 1/2 trials.

Methods

In LEAP 1, PORT III–V patients received LEF 150mg IV q12h for 5–7 days or MOX 400mg IV q24h for 7 days, with optional IV-to-oral switch (600mg LEF q12h or 400 mg MOX q24h). In LEAP 2, PORT II–IV patients received oral LEF 600mg q12h for 5 days or oral MOX 400mg q24h for 7 days. Patients with known QT prolongation or on medication with potential to prolong the QT interval were excluded as per MOX label. After 5 minutes of rest in the supine position, triplicate 12-lead ECGs were obtained within a 5-minute interval at Screening in both studies, on Days 1/3 in LEAP 1 (predose and ≤15 minutes after first IV dose), and on Days 1/4 in LEAP 2 (predose and 1–3 hours after first oral dose), and sent to a central ECG reader for adjudication.

Results

Of 1,282 randomized/treated patients (n = 641/group), 1,274 had baseline (BL) and post-BL ECG data (n = 636 LEF, n = 638 MOX). Consistent with the resolution of infection, ECGs revealed mean reductions of 7–8 beats/minute for both groups in both studies. The largest mean change in QTcF from BL to post-BL was on Day 3 in LEAP 1 (13.6 and 16.4 msec with IV LEF and MOX, respectively) and on Day 4 in LEAP 2 (9.3 and 11.6 msec with oral LEF and MOX, respectively). The proportion of patients meeting potentially important post-BL QTcF values/changes was comparable between treatment groups (table). In the standardized MedDRA query of Torsade de pointes/QT prolongation (broad), the most common treatment-emergent adverse event was ECG QT prolonged (n = 4 LEF, n = 5 MOX). All events were nonserious and mild or moderate in severity. 6 events were considered study drug related (n = 4 LEF, n = 2 MOX). 5 events led to study drug discontinuation (n = 2 LEF, n = 3 MOX). In 2 patients with cardiovascular disease, 1 had ventricular arrhythmia on Day 20 (18 days after last LEF dose) and 1 had cardiac arrest on Day 18 (9 days after last MOX dose); both events were fatal and considered unrelated to study drug by investigator.

Conclusion

Mild prolongation of the QTcF interval was seen with LEF and MOX, with somewhat smaller effects seen with LEF. Given the small effect, LEF is unlikely to pose a clinically significant risk of ventricular proarrhythmia with appropriate precautions and use.

Disclosures

All authors: No reported disclosures.

A randomized trial of human C1 inhibitor prophylaxis in children with hereditary angioedema

BACKGROUND

Patients with hereditary angioedema with C1 inhibitor deficiency or dysfunction have burdensome recurrent angioedema attacks. The safety, efficacy, and health-related quality of life (HRQoL) outcomes of C1 inhibitor (C1-INH) prophylaxis (intravenously administered) in patients aged 6-11 years were investigated.

METHODS

Eligible patients were enrolled in a randomized, single-blind, crossover, phase 3 trial. After a 12-week baseline observation period (BOP), patients received 500 or 1000 U C1-INH, twice weekly, for 12 weeks before crossing over to the alternate dose for 12 weeks. The primary efficacy end-point was the monthly normalized number of angioedema attacks (NNA). HRQoL was assessed using the EuroQoL 5-dimensional descriptive system youth version and visual analog scale (EQ-VAS).

RESULTS

Twelve randomized patients had a median (range) age of 10.0 (7-11) years. Mean (SD) percentage reduction in monthly NNA from BOP was 71.1% (27.1%) with 500 U and 84.5% (20.0%) with 1000 U C1-INH. Mean (SD) within-patient difference (-0.4 [0.58]) for monthly NNA with both doses was significant (P = 0.035 [90% CI, -0.706 to -0.102]). Cumulative attack severity, cumulative daily severity, and number of acute attacks treated were reduced. No serious adverse events or discontinuations occurred. Mean EQ-VAS change from BOP to week 9 of treatment (500 U C1-INH, 10.4; 1000 U C1-INH, 21.6) was greater than the minimal important difference, indicating a meaningful HRQoL change.

CONCLUSIONS

C1-INH prophylaxis was effective, safe, and well tolerated in children aged 6-11 years experiencing recurrent angioedema attacks. A post hoc analysis indicated a meaningful improvement in HRQoL with C1-INH.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT02052141.

Fixed-Dose Subcutaneous C1-Inhibitor Liquid for Prophylactic Treatment of C1-INH-HAE: SAHARA Randomized Study

BACKGROUND

Hereditary angioedema (HAE) with C1 inhibitor deficiency (C1-INH) is characterized by swelling of subcutaneous and/or submucosal tissues.

OBJECTIVE

To evaluate efficacy/safety of fixed-dose subcutaneous plasma-derived C1-INH (pdC1-INH) liquid for HAE attack prevention (NCT02584959).

METHODS

Eligible patients were ≥12 years with ≥2 monthly attacks prescreening or pre-long-term prophylaxis. In a partial crossover design, 80% of patients were randomized to placebo or pdC1-INH liquid for 14 weeks and crossed over from active to placebo or vice versa for another 14 weeks. The remainder were randomized to pdC1-INH liquid for 28 weeks. The primary efficacy endpoint was normalized number of attacks (NNA) versus placebo. Key additional endpoints were the proportion of patients achieving NNA reduction ≥50%, attack severity, number of attack-free days, and safety.

RESULTS

Seventy-five patients were randomized and 58 (77%) completed the study. Mean age 41 years; 88% HAE type I. Least-squares means of NNA were reduced from 3.9 with placebo to 1.6 with pdC1-INH (from day 1; P < .0001). Most patients had ≥50% NNA reduction with pdC1-INH (from day 1, 78%). A total of 8.8% of placebo-treated patients were attack-free and 5.3%, 22.8%, and 63.2% had mild, moderate, and severe attacks, respectively; 37.5% of pdC1-INH-treated patients were attack-free and 8.9%, 26.8%, and 26.8% had mild, moderate, and severe attacks, respectively. Treatment-emergent adverse event rates were similar between groups (52% vs 56% for pdC1-INH crossover vs placebo, respectively).

CONCLUSIONS

Fixed-dose subcutaneous pdC1-INH liquid was superior to placebo in preventing HAE attacks and demonstrated a favorable safety profile.

Effect of Lanadelumab Compared With Placebo on Prevention of Hereditary Angioedema Attacks: A Randomized Clinical Trial

IMPORTANCE

Current treatments for long-term prophylaxis in hereditary angioedema have limitations.

OBJECTIVE

To assess the efficacy of lanadelumab, a fully human monoclonal antibody that selectively inhibits active plasma kallikrein, in preventing hereditary angioedema attacks.

DESIGN, SETTING, AND PARTICIPANTS

Phase 3, randomized, double-blind, parallel-group, placebo-controlled trial conducted at 41 sites in Canada, Europe, Jordan, and the United States. Patients were randomized between March 3, 2016, and September 9, 2016; last day of follow-up was April 13, 2017. Randomization was 2:1 lanadelumab to placebo; patients assigned to lanadelumab were further randomized 1:1:1 to 1 of the 3 dose regimens. Patients 12 years or older with hereditary angioedema type I or II underwent a 4-week run-in period and those with 1 or more hereditary angioedema attacks during run-in were randomized.

INTERVENTIONS

Twenty-six-week treatment with subcutaneous lanadelumab 150 mg every 4 weeks (n = 28), 300 mg every 4 weeks (n = 29), 300 mg every 2 weeks (n = 27), or placebo (n = 41). All patients received injections every 2 weeks, with those in the every-4-week group receiving placebo in between active treatments.

MAIN OUTCOME AND MEASURES

Primary efficacy end point was the number of investigator-confirmed attacks of hereditary angioedema over the treatment period.

RESULTS

Among 125 patients randomized (mean age, 40.7 years [SD, 14.7 years]; 88 females [70.4%]; 113 white [90.4%]), 113 (90.4%) completed the study. During the run-in period, the mean number of hereditary angioedema attacks per month in the placebo group was 4.0; for the lanadelumab groups, 3.2 for the every-4-week 150-mg group; 3.7 for the every-4-week 300-mg group; and 3.5 for the every-2-week 300-mg group. During the treatment period, the mean number of attacks per month for the placebo group was 1.97; for the lanadelumab groups, 0.48 for the every-4-week 150-mg group; 0.53 for the every-4-week 300-mg group; and 0.26 for the every-2-week 300-mg group. Compared with placebo, the mean differences in the attack rate per month were -1.49 (95% CI, -1.90 to -1.08; P < .001); -1.44 (95% CI, -1.84 to -1.04; P < .001); and -1.71 (95% CI, -2.09 to -1.33; P < .001). The most commonly occurring adverse events with greater frequency in the lanadelumab treatment groups were injection site reactions (34.1% placebo, 52.4% lanadelumab) and dizziness (0% placebo, 6.0% lanadelumab).

CONCLUSIONS AND RELEVANCE

Among patients with hereditary angioedema type I or II, treatment with subcutaneous lanadelumab for 26 weeks significantly reduced the attack rate compared with placebo. These findings support the use of lanadelumab as a prophylactic therapy for hereditary angioedema. Further research is needed to determine long-term safety and efficacy.

TRIAL REGISTRATION

EudraCT Identifier: 2015-003943-20; ClinicalTrials.gov Identifier: NCT02586805.

LB6. Oral Lefamulin Is Safe and Effective in the Treatment of Adults With Community-Acquired Bacterial Pneumonia (CABP): Results of Lefamulin Evaluation Against Pneumonia (LEAP 2) Study

Background

Lefamulin, a first in class pleuromutilin, is being developed as an IV and oral formulation for treating CABP. The second of 2 phase 3 Lefamulin Evaluation Against Pneumonia studies, LEAP 2 (NCT02813694; EudraCT 2015-004782-92) evaluating an oral 5-day regimen, is presented here. LEAP 2 complements the positive results from LEAP 1, an IV-to-oral switch study in patients with PORT Risk Class III-V.

Methods

In this multicenter, randomized, double-blind, double dummy study, patients with CABP were randomized to oral lefamulin 600 mg q12h for 5 days or moxifloxacin 400 mg q24h for 7 days. Adults with PORT Risk Class II–IV were eligible (≥50% were to have PORT Risk Class III or IV). The US FDA primary endpoint was early clinical response (ECR) (96 ± 24 h after first dose) in the intent-to-treat (ITT) population. The EMA coprimary endpoints (FDA secondary endpoints) were investigator assessment of clinical response (IACR) at test of cure (TOC) (5–10 days after last dose) in the modified ITT (mITT) and clinically evaluable (CE) TOC populations. For FDA and EMA endpoints, noninferiority was concluded if the lower limit of the two-sided 95% CI was greater than –10% (Figure 1).

Results

A total of 738 patients were randomized (n = 370 lefamulin, n = 368 moxifloxacin). Five days of lefamulin was noninferior to 7 days of moxifloxacin for both FDA and EMA primary endpoints (Figure 2). Lefamulin was efficacious regardless of PORT Risk Class (ECR responder rates for PORT II, III, and IV: 91.8% [168/183], 91.0% [132/145], and 85.0% [34/40] for lefamulin; 93.1% [176/189], 90.2% [120/133], and 85.7% [36/42] for moxifloxacin, respectively). Both agents demonstrated similar ECR responder and IACR success rates across baseline CABP pathogens. Rates of serious adverse events (AEs) and AEs leading to discontinuation were low and similar between groups. Most frequently reported AEs were gastrointestinal, the majority of mild severity with few discontinuations.

Conclusion

Five-day oral lefamulin demonstrated noninferiority for both FDA and EMA efficacy endpoints vs. 7-day oral moxifloxacin. Both agents were safe and generally well tolerated. Lefamulin shows promise as an oral monotherapy with a complete spectrum of antibacterial activity against CABP pathogens.

Disclosures

E. Alexander, Nabriva: Employee and Shareholder, Salary and Stock Options. L. Goldberg, Nabriva: Employee, Employee Stock Options and Salary. A. Das, Achaogen: Consultant, Consulting fee. Cempra: Consultant, Consulting fee. Contrafect: Consultant, Consulting fee. Paratek: Consultant, Consulting fee. Tetraphase: Consultant, Consulting fee. Wockhardt: Consultant, Consulting fee. Theravance: Consultant, Consulting fee. Zavante: Consultant, Consulting fee. Utility: Consultant, Consulting fee. Former Employee of Nabriva: Employee, Salary. Nabriva: Consultant, Consulting fee. G. J. Moran, Nabriva: Scientific Advisor, Consulting fee. C. Sandrock, Nabriva: Consultant, Consulting fee. L. B. Gasink, Former Employee of Nabriva: Employee, Salary. P. Spera, Nabriva: Employee and Shareholder, Salary. C. Sweeney, Nabriva: Employee, Employee Stock Options and Salary. S. Paukner, Nabriva: Employee and Shareholder, Salary. W. W. Wicha, Nabriva: Employee and Shareholder, Salary. J. Schranz, Nabriva: Employee and Shareholder, Salary.

An open-label study to evaluate the long-term safety and efficacy of lanadelumab for prevention of attacks in hereditary angioedema: design of the HELP study extension

BACKGROUND

Hereditary angioedema (HAE) is characterized by recurrent attacks of subcutaneous or submucosal edema. Attacks are unpredictable, debilitating, and have a significant impact on quality of life. Patients may be prescribed prophylactic therapy to prevent angioedema attacks. Current prophylactic treatments may be difficult to administer (i.e., intravenously), require frequent administrations or are not well tolerated, and breakthrough attacks may still occur frequently. Lanadelumab is a subcutaneously-administered monoclonal antibody inhibitor of plasma kallikrein in clinical development for prophylaxis of hereditary angioedema attacks. A Phase 1b study supported its efficacy in preventing attacks. A Phase 3, randomized, double-blind, placebo-controlled, parallel-arm study has been completed and an open-label extension is currently ongoing.

METHODS/DESIGN

The primary objective of the open-label extension is to evaluate the long-term safety of repeated subcutaneous administrations of lanadelumab in patients with type I/II HAE. Secondary objectives include evaluation of efficacy and time to first angioedema attack to determine outer bounds of the dosing interval. The study will also evaluate immunogenicity, pharmacokinetics/pharmacodynamics, quality of life, characteristics of breakthrough attacks, ease of self-administration, and safety/efficacy in patients who switch to lanadelumab from another prophylactic therapy. The open-label extension will enroll patients who completed the double-blind study ("rollover patients") and those who did not participate in the double-blind study ("non-rollover patients"), which includes patients who may or may not be currently using another prophylactic therapy. Rollover patients will receive a single 300 mg dose of lanadelumab on Day 0 and the second dose after the patient's first confirmed angioedema attack. Thereafter, lanadelumab will be administered every 2 weeks. Non-rollover patients will receive 300 mg lanadelumab every 2 weeks regardless of the first attack. All patients will receive their last dose on Day 350 (maximum of 26 doses), and will then undergo a 4-week follow-up.

DISCUSSION

Prevention of attacks can reduce the burden of illness associated with HAE. Prophylactic therapy requires extended, repeated dosing and the results of this study will provide important data on the long-term safety and efficacy of lanadelumab, a monoclonal antibody inhibitor of plasma kallikrein for subcutaneous administration for the treatment of HAE. Trial registration NCT02741596.

Preventing Hereditary Angioedema Attacks in Children Using Cinryze®: Interim Efficacy and Safety Phase 3 Findings

BACKGROUND

Hereditary angioedema (HAE) is a rare genetic disease causing unpredictable and potentially life-threatening subcutaneous and submucosal edematous attacks. Cinryze® (Shire ViroPharma Inc., Lexington, MA, USA), a nanofiltered C1 inhibitor (C1-INH), is approved in Europe for the treatment, preprocedure prevention, and routine prophylaxis of HAE attacks, and for the routine prophylaxis of attacks in the USA. This phase 3 study assessed the safety and efficacy of 2 C1-INH doses in preventing attacks in children aged 6-11 years.

METHODS

A randomized single-blind crossover study was initiated in March 2014. Results for the first 6 patients completing the study are reported here. After a 12-week qualifying observation period, patients were randomly assigned to 1 of 2 C1-INH doses, 500 or 1,000 U, every 3-4 days for 12 weeks and crossed over to the alternative dose for a second 12-week period. The primary efficacy endpoint was the number of angioedema attacks per month.

RESULTS

Six females with HAE type I and a median age of 10.5 years received 2 doses of C1-INH (500 and 1,000 U). The mean (SD) difference in the number of monthly angioedema attacks between the baseline observation period and the treatment period was -1.89 (1.31) with 500 U and -1.89 (1.11) with 1,000 U. During the treatment periods, cumulative attack severity, cumulative daily severity, and the number of attacks needing acute treatment were lower. No serious adverse events or study drug discontinuations occurred.

CONCLUSIONS

Interim findings from this study indicate that routine prevention with intravenous administration of C1-INH is efficacious, safe, and well tolerated in children ≥6 years of age.

Treatment Effect and Safety of Icatibant in Pediatric Patients with Hereditary Angioedema

BACKGROUND

Clinical manifestations of hereditary angioedema with C1 inhibitor deficiency (C1-INH-HAE) usually begin in childhood, often intensifying during puberty. Currently there are insufficient efficacy/safety data for HAE therapies in children and adolescents due to the small number of pediatric patients enrolled in studies.

OBJECTIVE

The objective of this phase 3 study was to evaluate the efficacy/safety of a single subcutaneous dose of icatibant (0.4 mg/kg; maximum 30 mg) in pediatric patients with C1-INH-HAE.

METHODS

Patients aged 2 years to younger than 18 years were categorized as prepubertal (children) and pubertal/postpubertal (adolescents). The primary end point was time to onset of symptom relief-earliest time posttreatment to 20% or more improvement in composite symptom score.

RESULTS

Thirty-two patients received icatibant (safety population: 11 children with attack, 10 adolescents without attack, and 11 adolescents with attack). The efficacy population consisted of 11 children and 11 adolescents with edematous attacks. Most attacks in the efficacy population (16 [72.7%]) were cutaneous, 5 (22.7%) were abdominal, and 1 (4.5%) was both cutaneous and abdominal; none was laryngeal. Overall, the median time to onset of symptom relief was 1.0 hour, the same for children and adolescents. Thirty-two treatment-emergent adverse events (all mild or moderate) occurred in 9 (28.1%) patients. Gastrointestinal symptoms were most common (9 events in 3 [9.4%] patients). Injection-site reactions affected most (90.6%) patients (particularly erythema and swelling), but almost all resolved by 6 hours postdose. Icatibant demonstrated a monophasic plasma concentration-time profile. Time to peak concentration was approximately 0.5 hours postdose.

CONCLUSIONS

Symptom relief was rapid, and a single icatibant injection in pediatric patients with C1-INH-HAE was well tolerated (ClinicalTrials.gov identifier, NCT01386658).

Health-related quality of life with hereditary angioedema following prophylaxis with subcutaneous C1-inhibitor with recombinant hyaluronidase

BACKGROUND

To estimate health-related quality-of-life changes in patients with hereditary angioedema due to C1-inhibitor (C1-INH) deficiency who received subcutaneous C1-INH with recombinant hyaluronidase (rHuPH20) for attack prophylaxis in a randomized, double-blind, dose-ranging, cross-over study.

METHODS

Patients with type I/II hereditary angioedema received 1000 U of C1-INH with 24,000 U of rHuPH20 or 2000 U of C1-INH with 48,000 U of rHuPH20 every 3-4 days for 8 weeks and then crossed over for another 8-week period. The study was terminated early as a precaution related to non-neutralizing antibodies to rHuPH20. The Angioedema Quality of Life questionnaire (AE-QoL) was administered at weeks 1 and 5 of both periods, and at 1 week after the second treatment period. Changes in AE-QoL scores were calculated over both treatment periods and within each treatment period for patients with ≥4 weeks of treatment.

RESULTS

Forty-one patients had evaluable AE-QoL data, and 22 patients completed treatment. At screening, 43% of the patients were receiving intravenous C1-INH. A significant average AE-QoL total score decline (improvement) of -8.1 (95% confidence interval, -13.7 to -2.5) was observed from baseline to the end of the study, and significant AE-QoL score declines were observed in the Functioning, Fear/Shame, and Nutrition domains. Patients on 2000 U reported higher mean AE-QoL score declines in Functioning and Nutrition domains relative to the 1000 U dose. Overall, 43.9% of all the patients, 45.5% of the study completers, and 46.7% of the nonprophylaxis users at baseline on high treatment doses achieved a reduction in the AE-QoL total score of six points.

CONCLUSION

Despite early termination and prestudy prophylactic intravenous C1-INH use by 43% of the patients, improved AE-QoL scores were observed after ≤16 weeks of subcutaneous C1-INH-rHuPH20 prophylaxis.

Subcutaneous administration of human C1 inhibitor with recombinant human hyaluronidase in patients with hereditary angioedema

BACKGROUND

The currently approved method of C1 inhibitor (C1 INH) administration for patients with hereditary angioedema with C1 INH deficiency (HAE) is by intravenous injection. A C1 INH subcutaneous formulation may provide an attractive mode of administration for some patients.

OBJECTIVE

To evaluate efficacy and safety of two doses of subcutaneous, plasma-derived C1 INH with the dispersing agent, recombinant human hyaluronidase (rHuPH20) to prevent angioedema attacks in patients with HAE.

METHODS

A randomized, double-blind, dose-ranging, crossover study, patients 12 years of age (n = 47) with a confirmed diagnosis of HAE were randomly assigned to receive subcutaneous injections of 1000 U C1 INH with 24,000 U rHuPH20 or 2000 U C1 INH with 48,000 U rHuPH20 every 3 or 4 days for 8 weeks and then crossed-over for another 8-week period. The primary efficacy end point was the number of angioedema attacks during each treatment period.

RESULTS

The study was terminated early as a precaution related to non-neutralizing antibodies to rHuPH20 in 45% of patients. The mean standard deviation number of angioedema attacks during the 8-week treatment periods were 1.58 1.59 with 1000 U C1 INH and 0.97 1.26 with 2000 U. The mean (95% confidence interval [CI]) within-patient difference (2000 U-1000 U, respectively) was 0.61 (95% CI, 1.23 to 0.01) attacks per month (p = 0.0523), and 0.56 (95% CI, 1.06 to 0.05) attacks that required acute treatment, (p = 0.0315). No deaths or other serious adverse events were reported. Injection-site reaction was the most common adverse event.

CONCLUSION

Despite early termination, this study demonstrated a clinically and statistically significant difference in burden of disease, which favored 2000 U C1 INH, without associated serious adverse events.

Safety and efficacy of C1 esterase inhibitor for acute attacks in children with hereditary angioedema

BACKGROUND

Human plasma-derived nanofiltered C1 esterase inhibitor (C1 INH-nf) is used to treat acute angioedema attacks in patients with hereditary angioedema (HAE), but data regarding use in children are sparse.

METHODS

Patients 2 to <12 years of age, body weight ≥10 kg, with a diagnosis of HAE type I or II, were recruited for a multicenter open-label trial. Patients were recruited into 2 weight categories (10-25 kg, >25 kg). Each weight category included 2 dosing levels: C1 INH-nf (500 units [U], 1000 U) and C1 INH-nf (1000 U, 1500 U), respectively. Patients experiencing an angioedema attack were given a single intravenous dose. Primary efficacy end-point was the onset of unequivocal relief of the defining symptom within 4 h following initiation of C1 INH-nf treatment.

RESULTS

Nine children were treated: 3 (10-25 kg) received 500 U; 3 (>25 kg) received 1000 U; and 3 (>25 kg) received 1500 U. The lower weight/higher dose category (10-25 kg, 1000 U) was not successfully enrolled. All patients completed the study. Most angioedema attacks (n = 5) were abdominal. All patients met the primary end-point; median time to unequivocal symptom relief was 0.5 (range: 0.25-2.5) h. Doses of C1 INH-nf ranged from 20.8 to 51.9 U/kg.

CONCLUSIONS

Treatment of a single angioedema attack with C1 INH-nf doses of 500 U (in patients 10-25 kg), 1000 U, and 1500 U (in patients >25 kg) were well tolerated. Doses of C1 INH-nf <1000 U may be appropriate in some pediatric patients.

Escalating doses of C1 esterase inhibitor (CINRYZE) for prophylaxis in patients with hereditary angioedema

BACKGROUND

Nanofiltered C1 inhibitor (human) is approved in the United States for routine prophylaxis of angioedema attacks in patients with hereditary angioedema, a rare disease caused by a deficiency of functional C1 inhibitor.

OBJECTIVE

To assess the safety of escalating doses of nanofiltered C1 inhibitor (human) in patients who were not adequately controlled on the indicated dose (1000 U every 3 or 4 days).

METHODS

Eligible patients had >1 attack/month over the 3 months before the trial. Doses were escalated to 1500 U every 3 or 4 days for 12 weeks, at which point, the patients were evaluated. If treatment was successful (≤1 attack/mo) or at the investigator's discretion, the patients entered a 3-month follow-up period. The patients with an average of >1 attack/month were eligible for further escalation to 2000 U and then 2500 U.

RESULTS

Twenty patients started at 1500 U; 13 were escalated to 2000 U, and 12 were escalated to 2500 U. Eighteen patients reported adverse events. Two patients reported 4 serious adverse events (cerebral cystic hygroma, laryngeal angioedema attack, anemia, and bile duct stone) that were considered by investigators to be unrelated to treatment. Notably, there were no systemic thrombotic events or discontinuations due to adverse events. Fourteen patients were treated successfully (70%), continued to the follow-up period at the investigator's discretion, or experienced a reduction in attacks of >1.0/month.

CONCLUSIONS

Dose escalation of nanofiltered C1 inhibitor (human) up to 2500 U was well tolerated and reduced attack frequency in the majority of patients.

Safety and Pharmacokinetics of Coadministered Voriconazole and Anidulafungin

There is considerable interest in combining echinocandin and triazole antifungal agents for treatment of invasive fungal infections; however, information is needed regarding the tolerability and potential for pharmacokinetic interactions. Anidulafungin is a semisynthetic echinocandin, and voriconazole is an extended-spectrum triazole. In a random sequence, 17 subjects received anidulafungin with placebo, voriconazole with placebo, and anidulafungin with voriconazole. Anidulafungin was administered intravenously: 200 mg on day 1, then 100 mg/d on days 2 through 4. Voriconazole was administered orally: 400 mg every 12 hours on day 1, then 200 mg every 12 hours on days 2 to 4. No dose-limiting toxicities or serious adverse events occurred, and all adverse events were mild and consistent with the known safety profiles of both drugs. Pharmacokinetic parameters were not affected by coadministration. The geometric mean ratio (90% confidence interval) of the combination/drug alone for AUC(SS) was 97.4% (94.9-99.9), 97.4% (92.1-103.0), and 94.4% (87.0-102.5) for anidulafungin, voriconazole, and the voriconazole metabolite, respectively.

Anidulafungin versus fluconazole for invasive candidiasis

BACKGROUND

Anidulafungin, a new echinocandin, has potent activity against candida species. We compared anidulafungin with fluconazole in a randomized, double-blind, noninferiority trial of treatment for invasive candidiasis.

METHODS

Adults with invasive candidiasis were randomly assigned to receive either intravenous anidulafungin or intravenous fluconazole. All patients could receive oral fluconazole after 10 days of intravenous therapy. The primary efficacy analysis assessed the global response (clinical and microbiologic) at the end of intravenous therapy in patients who had a positive baseline culture. Efficacy was also assessed at other time points.

RESULTS

Eighty-nine percent of the 245 patients in the primary analysis had candidemia only. Candida albicans was isolated in 62% of the 245 patients. In vitro fluconazole resistance was infrequent. Most of the patients (97%) did not have neutropenia. At the end of intravenous therapy, treatment was successful in 75.6% of patients treated with anidulafungin, as compared with 60.2% of those treated with fluconazole (difference, 15.4 percentage points; 95% confidence interval [CI], 3.9 to 27.0). The results were similar for other efficacy end points. The statistical analyses failed to show a "center effect"; when data from the site enrolling the largest number of patients were removed, success rates at the end of intravenous therapy were 73.2% in the anidulafungin group and 61.1% in the fluconazole group (difference, 12.1 percentage points; 95% CI, -1.1 to 25.3). The frequency and types of adverse events were similar in the two groups. The rate of death from all causes was 31% in the fluconazole group and 23% in the anidulafungin group (P=0.13).

CONCLUSIONS

Anidulafungin was shown to be noninferior to fluconazole in the treatment of invasive candidiasis. (ClinicalTrials.gov number, NCT00056368 [ClinicalTrials.gov]).

Indirect effects associated with widespread vaccination of infants with heptavalent pneumococcal conjugate vaccine (PCV7; Prevnar)

Prevnar (heptavalent pneumococcal conjugate vaccine; PCV7) provides protection against invasive pneumococcal disease (IPD) caused by vaccine serotypes. Indirect protection of non-immunised individuals may be the consequence of decreased transmission of vaccine serotypes, generally carried in the nasopharynx of infants and young children. This review summarises published reports of IPD incidence (1998-2005) among non-immunised individuals in countries with universal PCV7 immunisation. Findings suggest that non-immunised individuals benefit from indirect protection following widespread vaccination, enhancing cost-benefit evaluations of vaccination programs. Continued surveillance will be important, to follow future changes associated with non-vaccine type IPD, particularly among individuals with medical co-morbidities that may put them at higher risk of disease.

Safety and pharmacokinetics of intravenous anidulafungin in children with neutropenia at high risk for invasive fungal infections

Anidulafungin is an echinocandin with activity against Candida species and Aspergillus species. Adult dosages under study are 50 mg/day for esophageal candidiasis and 100 mg/day for invasive candidiasis and aspergillosis. Little is known, however, about the safety and pharmacokinetics of anidulafungin in children. A multicenter, ascending-dosage study of neutropenic pediatric patients was therefore conducted. Patients were divided into two age cohorts (2 to 11 years and 12 to 17 years) and were enrolled into sequential groups to receive 0.75 or 1.5 mg/kg of body weight/day. Blood samples were obtained following the first and fifth doses. Anidulafungin was assayed in plasma, and pharmacokinetic parameters were determined. Safety was assessed using National Cancer Institute (NCI) common toxicity criteria. Pharmacokinetic parameters were determined for 12 patients at each dosage (0.75 mg/kg/day or 1.5 mg/kg/day). Concentrations and drug exposures were similar for patients between age cohorts, and weight-adjusted clearance was consistent across age. No drug-related serious adverse events were observed. One patient had fever (NCI toxicity grade of 3), and one patient had facial erythema, which resolved with slowing the infusion rate. Anidulafungin in pediatric patients was well tolerated and can be dosed based on body weight. Pediatric patients receiving 0.75 mg/kg/day or 1.5 mg/kg/day have anidulafungin concentration profiles similar to those of adult patients receiving 50 or 100 mg/day, respectively.

[Bronchial obstruction by an aberrant left pulmonary artery misdiagnosed as asthma in a 7 year old child]

INTRODUCTION

Wheezing is common symptom in infants and is usually due to asthma. However an alternative diagnosis should be sought if there is no reversibility to B2-agonist.

CASE REPORT

This case report describes a 7 years old child who had been treated for poorly controlled asthma for several years. The absence of B2-agonist reversibility, indirect signs of thoracic straining on spirometry and evidence of right heart decompensation raised doubts about the diagnosis. CT angiography demonstrated a pulmonary artery malformation. Formal pulmonary angiography confirmed the diagnosis of pulmonary artery sling. This malformation had been causing intermittent bronchial compression and the symptoms resolved after surgical intervention.

CONCLUSION

Wheezing symptoms over two Years in a child, misdiagnosed as asthma, is an unusual presentation of this pulmonary vascular anomaly.

Effects of ritonavir on indinavir pharmacokinetics in cerebrospinal fluid and plasma

Therapeutic control of human immunodeficiency virus type 1 (HIV-1) in peripheral compartments does not assure control in the central nervous system. Inadequate drug penetration may provide a sanctuary from which resistant virus can emerge or allow development of psychomotor abnormalities. To characterize the effect of ritonavir on indinavir disposition into cerebrospinal fluid, seven HIV-infected adults underwent intensive sampling at steady-state while receiving twice-daily indinavir (800 mg) and ritonavir (100 mg). Serial cerebrospinal fluid and plasma samples were obtained at 10 time points from each subject. Free indinavir accounted for 98.6% of drug in cerebrospinal fluid and 55.9% in plasma. Mean cerebrospinal fluid C(max), C(min), and area under the concentration-time curve from 0 to 12 h (AUC(0-12)) values for free indinavir were 735 nM, 280 nM, and 6502 nM h(-1), respectively, and the free levels exceeded 100 nM in every sample. The cerebrospinal fluid/plasma AUC(0-12) ratio for free indinavir was 17.5% +/- 6.4%. This ratio was remarkably similar to results obtained in a previous study in which subjects received indinavir without ritonavir, indicating that ritonavir did not have a substantial direct effect on the barrier to indinavir penetration into cerebrospinal fluid. Low-dose ritonavir increases cerebrospinal fluid indinavir concentrations substantially more than 800 mg of indinavir given thrice daily without concomitant ritonavir, despite a lower total daily indinavir dose.

Aspergillosis case-fatality rate: systematic review of the literature

To update the case-fatality rate (CFR) associated with invasive aspergillosis according to underlying conditions, site of infection, and antifungal therapy, data were systematically reviewed and pooled from clinical trials, cohort or case-control studies, and case series of >/=10 patients with definite or probable aspergillosis. Subjects were 1941 patients described in studies published after 1995 that provided sufficient outcome data; cases included were identified by MEDLINE and EMBASE searches. The main outcome measure was the CFR. Fifty of 222 studies met the inclusion criteria. The overall CFR was 58%, and the CFR was highest for bone marrow transplant recipients (86.7%) and for patients with central nervous system or disseminated aspergillosis (88.1%). Amphotericin B deoxycholate and lipid formulations of amphotericin B failed to prevent death in one-half to two-thirds of patients. Mortality is high despite improvements in diagnosis and despite the advent of newer formulations of amphotericin B. Underlying patient conditions and the site of infection remain important prognostic factors.