Immediate and sustained terminal complement inhibition with ravulizumab in patients with anti-aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder

Objective

To assess the pharmacokinetics and pharmacodynamics of the long-acting terminal complement 5 (C5) inhibitor ravulizumab in adults with anti-aquaporin-4 antibody-positive (AQP4+) neuromyelitis optica spectrum disorder (NMOSD) in the phase 3, open-label CHAMPION-NMOSD trial (NCT04201262).

Methods

Patients aged 18 years or older received a weight-based intravenous loading dose of ravulizumab (2,400-3,000 mg) on day 1, followed by weight-based maintenance doses (3,000-3,600 mg) on day 15 and once every 8 weeks thereafter. Pharmacokinetic assessments were maximum observed concentration (Cmax, assessed at the end of the infusion) and concentration at the end of the dosing interval (Ctrough, assessed before dosing) for ravulizumab. Pharmacodynamic assessment was time-matched observed free C5 concentration in serum up to 50 weeks.

Results

The pharmacokinetic/pharmacodynamic analysis included 58 patients treated with ravulizumab. Serum ravulizumab concentrations at or above the therapeutic threshold (175 μg/mL) were achieved in all patients after administration of the first dose and maintained for 50 weeks. At week 50, the mean (standard deviation) Cmax (n = 51) and Ctrough (n = 52) were 1,887.6 (411.38) and 764.4 (217.68) μg/mL, respectively. Immediate and complete terminal complement inhibition (free C5 serum concentrations < 0.5 μg/mL) was achieved by the end of the first ravulizumab infusion and sustained throughout the treatment period. No treatment-emergent antibodies to ravulizumab were observed. No impact on ravulizumab pharmacokinetics was seen for age, sex, race, hematocrit, hemoglobin, markers of renal and liver impairment, or medications commonly used by patients with NMOSD. Body weight and BMI were significant covariates of ravulizumab pharmacokinetics.

Conclusions

Serum ravulizumab concentrations were maintained above the therapeutic threshold in all patients through 50 weeks of treatment. Ravulizumab achieved immediate and complete terminal complement inhibition that was sustained throughout the treatment period in adults with AQP4+ NMOSD.

Understanding Burnout Among US Radiation Oncology Residents

PURPOSE/OBJECTIVE(S)

Burnout is a significant concern among medical residents in the United States, including those in radiation oncology. This study aims to understand the extent of burnout among radiation oncology residents and identify modifiable factors within program structure and benefits that may help improve overall wellness and reduce burnout.

MATERIALS/METHODS

A Qualtrics-based survey was administered to US radiation oncology program directors and coordinators, utilizing contact information gathered in FREIDA, with a request to forward to all residents. The survey included questions on benefits and program structure as well as the Maslach Burnout Inventory. Data was analyzed using descriptive statistics.

RESULTS

To date, 82 of 736 residents (11.1%) completed the survey with representation from all PGY-levels. Median participant age was 31, and 53% identified as male. 20% of surveyed residents feel emotionally drained from work a few times a week and 6% feel emotionally drained daily. 59% feel burned out from work at least a few times a month, with 6% feeling burned out daily. Despite this, 85% feel they are positively influencing other people's lives through their work at least weekly and 77% feel they have accomplished many worthwhile things in this job at least weekly. 65% have salaries between $60,000-$74,999, and 35% have the opportunity to moonlight for supplemental income. 49% have 3 weeks of vacation and 48% have 4 weeks. 27% reported their department had funded wellness events. 61% reported dual coverage rotations, with 40% requiring coverage of multiple attendings in one day. 65% reported protected academic time on all rotations, and 7% have no protected academic time. 48% of respondents have 12 months of research time. 85% and 36% of those with research and protected academic time, respectively, can complete this off-site. Respondent concerns include the job market (62%), declining personal fertility in residency (46%), and cost of living (40%). The most reported ways to decrease stress and anxiety were exercise (35%), a strong support system (34%), and spirituality (10%). Increased salary was identified as the top benefit that could improve wellness by 41 residents, while retirement matching (32), paid gym memberships (23), a personal wellness stipend (30), and free/subsidized childcare (16) were also ranked among the top 5 benefit changes that could improve wellness. Increased mid-level support (16), more protected academic time during the week (15), and flexibility with work location during academic/research time (13) were the top aspects of program structure that were reported as opportunities to improve wellness.

CONCLUSION

Burnout is prevalent among US radiation oncology residents, and changes to residency programs and expanded institutional benefits are strongly perceived as the key components to improved resident wellness. This study highlights the need for further investigation into the root causes of burnout and the development of evidence-based strategies.

Ravulizumab pharmacokinetics and pharmacodynamics in patients with generalized myasthenia gravis

INTRODUCTION

The terminal complement C5 inhibitor ravulizumab has a long elimination half-life, allowing maintenance dosing every 8 weeks. In the 26-week, double-blind, randomized, placebo-controlled period (RCP) of the CHAMPION MG study, ravulizumab provided rapid and sustained efficacy and was well tolerated in adults with anti-acetylcholine receptor antibody-positive (AChR Ab+) generalized myasthenia gravis (gMG). This analysis evaluated the pharmacokinetics (PK), pharmacodynamics (PD), and potential immunogenicity of ravulizumab in adults with AChR Ab+ gMG.

METHODS

Data were analyzed from 86 patients who received ravulizumab in the CHAMPION MG RCP. Ravulizumab dosing was weight-based: initial loading dose of 2400/2700/3000 mg on Day 1 and maintenance doses of 3000/3300/3600 mg on Day 15 and then every 8 weeks. PK parameters were estimated from serum ravulizumab concentrations determined pre- and post-dose; PD effects of ravulizumab on serum free C5 concentrations were measured; and immunogenicity was assessed using anti-drug antibody and neutralizing-antibody assays.

RESULTS

Target serum ravulizumab concentrations (> 175 µg/mL) were achieved immediately after the first ravulizumab dose (within 30 min of infusion completion) and maintained throughout the 26-week treatment period irrespective of patient body weight. Following the final maintenance dose, mean C_max was 1548 µg/mL and C_trough 587 µg/mL; no meaningful differences were noted among body-weight categories. Inhibition of serum free C5 was immediate, complete (< 0.5 μg/mL), and sustained throughout treatment in all patients. No treatment-emergent anti-drug antibodies were observed.

CONCLUSIONS

PK/PD evidence supports the use of ravulizumab every 8 weeks for immediate, complete, and sustained inhibition of terminal complement C5 in adults with AChR Ab+ gMG.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT03920293 (April 18, 2019).

Phase 3 Study of Subcutaneous Versus Intravenous Ravulizumab in Eculizumab-Experienced Adult Patients with PNH: Primary Analysis and 1-Year Follow-Up

INTRODUCTION

This study compared the pharmacokinetics (PK) of the ravulizumab on-body delivery system for subcutaneous (SUBQ) administration with intravenous (IV) ravulizumab in eculizumab-experienced patients with paroxysmal nocturnal hemoglobinuria (PNH).

METHODS

Patients with PNH received SUBQ ravulizumab (n = 90) or IV ravulizumab (n = 46) during the 10-week randomized treatment period; all patients then received SUBQ ravulizumab during an extension period (< 172 weeks; data cutoff 1 year). Primary endpoint was day 71 serum ravulizumab trough concentration (C_trough). Secondary endpoints were ravulizumab C_trough and free C5 over time. Efficacy endpoints included change in lactate dehydrogenase (LDH), breakthrough hemolysis (BTH), transfusion avoidance, stabilized hemoglobin, and Treatment Administration Satisfaction Questionnaire (TASQ) score. Safety, including adverse events (AEs) and adverse device effects (ADEs), was assessed until data cutoff.

RESULTS

SUBQ ravulizumab demonstrated PK non-inferiority with IV ravulizumab (day 71 SUBQ/IV geometric least-squares means ratio 1.257 [90% confidence interval 1.160-1.361; p < 0.0001]). Through 1 year of SUBQ administration, ravulizumab C_trough values were > 175 μg/mL (PK threshold) and free C5 < 0.5 μg/mL (PD threshold). Efficacy endpoints remained stable: mean (standard deviation, SD) LDH percentage change was 0.9% (20.5%); BTH events, 5/128 patients (3.9%); 83.6% achieved transfusion avoidance; 79.7% achieved stabilized hemoglobin. Total TASQ score showed improved satisfaction with SUBQ ravulizumab compared with IV eculizumab (mean [SD] change at SUBQ day 351, - 69.3 [80.1]). The most common AEs during SUBQ treatment (excluding ADEs) were headache (14.1%), COVID-19 (14.1%), and pyrexia (10.9%); the most common ADE unrelated to a device product issue was injection site reaction (4.7%). Although many patients had ≥ 1 device issue-related ADE, full SUBQ dose administration was achieved in 99.9% of attempts.

CONCLUSIONS

SUBQ ravulizumab provides an additional treatment choice for patients with PNH. Patients may switch to SUBQ ravulizumab from IV eculizumab or ravulizumab without loss of efficacy.

TRIAL REGISTRATION

NCT03748823.

The long-acting C5 inhibitor, ravulizumab, is efficacious and safe in pediatric patients with atypical hemolytic uremic syndrome previously treated with eculizumab

BACKGROUND

Atypical hemolytic uremic syndrome (aHUS) is a rare, complement-mediated disease associated with poor outcomes if untreated. Ravulizumab, a long-acting C5 inhibitor developed through minimal, targeted modifications to eculizumab was recently approved for the treatment of aHUS. Here, we report outcomes from a pediatric patient cohort from the ravulizumab clinical trial (NCT03131219) who were switched from chronic eculizumab to ravulizumab treatment.

METHODS

Ten patients received a loading dose of ravulizumab on Day 1, followed by maintenance doses administered initially on Day 15, and then, every 4-8 weeks thereafter, depending on body weight. All patients completed the initial evaluation period of 26 weeks and entered the extension period.

RESULTS

No patients required dialysis at any point throughout the study. The median estimated glomerular filtration rate values remained stable during the trial: 99.8 mL/min/1.73m2 at baseline, 93.5 mL/min/1.73m2 at 26 weeks, and 104 mL/min/1.73m2 at 52 weeks. At last available follow-up, all patients were in the same chronic kidney disease stage as recorded at baseline. Hematologic variables (platelets, lactate dehydrogenase, and hemoglobin) also remained stable throughout the initial evaluation period and up to the last available follow-up. All patients experienced adverse events; the most common were upper respiratory tract infection (40%) and oropharyngeal pain (30%). There were no meningococcal infections reported, no deaths occurred, and no patients discontinued during the study.

CONCLUSIONS

Overall, treatment with ravulizumab in pediatric patients with aHUS who were previously treated with eculizumab resulted in stable kidney and hematologic parameters, with no unexpected safety concerns when administered every 4-8 weeks.

TRIAL REGISTRATION

Trial identifiers: Trial ID: ALXN1210-aHUS-312 Clinical trials.gov : NCT03131219 EudraCT number: 2016-002499-29 Graphical abstract.

One-year outcomes from a phase 3 randomized trial of ravulizumab in adults with paroxysmal nocturnal hemoglobinuria who received prior eculizumab

Ravulizumab every 8 weeks showed non‐inferiority to eculizumab every 2 weeks in a 26‐week, phase 3, randomized controlled trial in adults with paroxysmal nocturnal hemoglobinuria (PNH) who were clinically stable on eculizumab (NCT03056040). We report results from the first 26 weeks of the extension period in which patients continued ravulizumab (n = 96) or switched from eculizumab to ravulizumab (n = 95). At week 52, mean (SD) lactate dehydrogenase levels increased 8.8% (29%) with ravulizumab‐ravulizumab and 5.8% (27%) with eculizumab‐ravulizumab from primary evaluation period baseline. During the extension period, four patients (ravulizumab‐ravulizumab, n = 3; eculizumab‐ravulizumab, n = 1) experienced breakthrough hemolysis, but none associated with serum free C5 ≥ 0.5 μg/mL. Mean Functional Assessment of Chronic Illness Therapy (FACIT)‐Fatigue scores remained stable through week 52. During the extension period, proportions of patients avoiding transfusion remained stable (ravulizumab‐ravulizumab, 86.5%; eculizumab‐ravulizumab, 83.2%); 81.2% and 81.1%, respectively, had stabilized hemoglobin. All patients maintained serum free C5 levels < 0.5 μg/mL. Adverse events were generally similar between groups, and rates were lower in the extension period. Adults with PNH on stable eculizumab therapy who received ravulizumab over 52 weeks experienced durable efficacy, with consistent efficacy in patients who received eculizumab during the primary evaluation period and then switched to ravulizumab. Ravulizumab was well tolerated.

Characterization of breakthrough hemolysis events observed in the phase 3 randomized studies of ravulizumab versus eculizumab in adults with paroxysmal nocturnal hemoglobinuria

Eculizumab is first-line treatment for paroxysmal nocturnal hemoglobinuria (PNH); however, approximately 11-27% of patients may experience breakthrough hemolysis (BTH) on approved doses of eculizumab. Ravulizumab, a new long-acting C5 inhibitor with a four times longer mean half-life than eculizumab, provides immediate, complete, and sustained C5 inhibition over 8-week dosing intervals. In two phase III studies, ravulizumab was non-inferior to eculizumab (Pinf ≤0.0004) for the BTH endpoint; fewer patients experienced BTH with ravulizumab versus eculizumab in both studies (301 [complement inhibitor−naïve patients], 4.0% vs. 10.7%; 302 [patients stabilized on eculizumab at baseline], 0% vs. 5.1%). In the current analysis, patientlevel data were evaluated to assess causes and clinical parameters associated with incidents of BTH reported during the 26-week treatment periods in the ravulizumab phase III PNH studies. Of the five BTH events occurring in ravulizumab-treated patients across the studies, none were temporally associated with suboptimal C5 inhibition (free C5 ≥0.5 mg/mL); four (80%) were temporally associated with complement-amplifying conditions (CAC). Of the 22 events occurring in eculizumab-treated patients, 11 were temporally associated with suboptimal C5 inhibition, including three events also associated with concomitant infection. Six events were associated with CAC only. Five events were unrelated to free C5 elevation or reported CAC. These results suggest that the immediate, complete, and sustained C5 inhibition achieved through weight-based dosing of ravulizumab reduces the risk of BTH by eliminating BTH associated with suboptimal C5 inhibition in patients with PNH. (Registered at clinicaltrials.gov identifiers: Study 301, NCT02946463; Study 302, NCT03056040.)

The long-acting C5 inhibitor, ravulizumab, is effective and safe in pediatric patients with atypical hemolytic uremic syndrome naïve to complement inhibitor treatment

Ravulizumab, a long-acting complement C5 inhibitor engineered from eculizumab, allows extending maintenance dosing from every 2-3 weeks to every 4-8 weeks depending on bodyweight. Here, we evaluated the efficacy and safety of ravulizumab in complement inhibitor-naïve children (under 18 years) with atypical hemolytic uremic syndrome. In this phase III, single-arm trial, ravulizumab was administered every eight weeks in patients 20 kg and over, and four weeks in patients under 20 kg. The primary endpoint was a complete thrombotic microangiopathy response (normalization of platelet count and lactate dehydrogenase, and a 25% or more improvement in serum creatinine) through 26 weeks. Secondary endpoints included change in hematologic parameters and kidney function. 18 patients with a median age of 5.2 years were evaluated. At baseline, symptoms of atypical hemolytic uremic syndrome outside the kidney were present in 72.2% of patients and 38.9% had been in intensive care. Baseline estimated glomerular filtration rate was 22 mL/min/1.73 m². By week 26, 77.8% of patients achieved a complete thrombotic microangiopathy response; 94.4%, 88.9% and 83.3% of patients achieved platelet normalization, lactate dehydrogenase normalization and a 25% or more improvement in serum creatinine, respectively. By week 50, 94.4% patients had achieved a complete thrombotic microangiopathy response. Median improvement in platelet count was 246 and 213 x10⁹/L through week 26 and week 50, respectively. The median increase above baseline in estimated glomerular filtration rate was 80 and 94 mL/min/1.73m² through week 26 and week 50, respectively. No unexpected adverse events, deaths, or meningococcal infections occurred. Thus, ravulizumab rapidly improved hematologic and kidney parameters with no unexpected safety concerns in complement inhibitor-naïve children with atypical hemolytic uremic syndrome.

One-year efficacy and safety of ravulizumab in adults with paroxysmal nocturnal hemoglobinuria naïve to complement inhibitor therapy: open-label extension of a randomized study

Background:

Ravulizumab, the only long-acting complement C5 inhibitor for adults with paroxysmal nocturnal hemoglobinuria (PNH), demonstrated non-inferiority to eculizumab after 26 weeks of treatment in complement inhibitor-naïve patients during a phase III randomized controlled trial. We present open-label extension results with up to 52 weeks of treatment.

Methods:

Patients assigned to ravulizumab every 8 weeks (q8w) or eculizumab every 2 weeks during the randomized primary evaluation period received ravulizumab q8w during the 26-week extension. Efficacy endpoints were lactate dehydrogenase (LDH) normalization, transfusion avoidance, breakthrough hemolysis (BTH), LDH levels, Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue scale, and stabilized hemoglobin. Serum free C5 levels and safety were assessed. Outcomes as of the data cut-off (4 September 2018) were summarized using descriptive statistics.

Results:

Overall, 124 patients continued ravulizumab, and 119 switched from eculizumab to ravulizumab. During the extension, 43.5% and 40.3% of patients in the ravulizumab–ravulizumab and eculizumab–ravulizumab arms, respectively, achieved LDH normalization; 76.6% and 67.2% avoided transfusion. BTH decreased in the eculizumab–ravulizumab arm; no events were associated with free C5 ⩾0.5 μg/mL while receiving ravulizumab. Overall, 73.4% and 65.5% of patients in the ravulizumab–ravulizumab and eculizumab–ravulizumab arms, respectively, achieved stabilized hemoglobin. Similar proportions of patients achieved ⩾3-point improvement in FACIT-Fatigue at week 52 (ravulizumab–ravulizumab, 64.5%; eculizumab–ravulizumab, 57.1%). All patients maintained free C5 <0.5 μg/mL during the ravulizumab extension, including those who experienced C5 excursions ⩾0.5 μg/mL while receiving eculizumab during the primary evaluation period. Adverse events were comparable between groups and decreased over time.

Conclusion:

In adult, complement inhibitor–naïve patients with PNH, ravulizumab q8w for up to 52 weeks demonstrated durable efficacy and was well tolerated, with complete and sustained free C5 inhibition and a decreased incidence of BTH with no events associated with loss of free C5 control.

Trial registration:

ClinicalTrials.gov identifier, NCT02946463

A Phase 3 Open-label, Randomized, Controlled Study to Evaluate the Efficacy and Safety of Intravenously Administered Ravulizumab Compared with Best Supportive Care in Patients with COVID-19 Severe Pneumonia, Acute Lung Injury, or Acute Respiratory Distress Syndrome: A structured summary of a study protocol for a randomised controlled trial

Objectives

Primary Objective

• To evaluate the effect of ravulizumab, a long-acting complement (C5) inhibitor plus best supportive care (BSC) compared with BSC alone on the survival of patients with COVID-19.

Secondary Objectives

• Number of days free of mechanical ventilation at Day 29

• Duration of intensive care unit stay at Day 29

• Change from baseline in Sequential Organ Failure Assessment (SOFA) score at Day 29

• Change from baseline in peripheral capillary oxygen saturation/ fraction of inspired oxygen (SpO2 /FiO2) at Day 29

• Duration of hospitalization at Day 29

• Survival (based on all-cause mortality) at Day 60 and Day 90

Safety

• Incidence of treatment-emergent adverse events and treatment-emergent serious adverse events.

PK/PD/Immunogenicity

• Change in serum ravulizumab concentrations over time

• Change in serum free and total C5 concentrations over time

• Incidence and titer of anti-ALXN1210 antibodies

Biomarkers

• Change in absolute level of soluble biomarkers in blood associated with complement activation, inflammatory processes, and hypercoagulable states over time

Exploratory

• Incidence of progression to renal failure requiring dialysis at Day 29

• Time to clinical improvement (based on a modified 6-point ordinal scale) over 29 days

• SF-12 Physical Component Summary (PCS) and Mental Component Summary (MCS) scores at Day 29 (or discharge), Day 60, and Day 90

• EuroQol 5-dimension 5-level (EQ-5D-5L) scores at Day 29 (or discharge), Day 60, and Day 90

Trial design

This is a multicenter Phase 3, open-label, randomized, controlled, study.

The study is being conducted in acute care hospital settings in the United States, United Kingdom, Spain, France, Germany, and Japan.

Participants

Male or female patients at least 18 years of age, weighing ≥ 40 kg, admitted to a designated hospital facility for treatment will be screened for eligibility in this study.

Key Inclusion criteria

• Confirmed diagnosis of SARS-CoV-2 infection (eg, via polymerase chain reaction [PCR] and/or antibody test) presenting as severe COVID-19 requiring hospitalization

• Severe pneumonia, acute lung injury, or ARDS confirmed by computed tomography (CT) or X-ray at Screening or within the 3 days prior to Screening, as part of the patient’s routine clinical care

• Respiratory distress requiring mechanical ventilation, which can be either invasive (requiring endotracheal intubation) or non-invasive (with continuous positive airway pressure [CPAP] or bilevel positive airway pressure [BiPAP])

Key Exclusion criteria

• Patient is not expected to survive for more than 24 hours

• Patient is on invasive mechanical ventilation with intubation for more than 48 hours prior to Screening

• Severe pre-existing cardiac disease (ie, NYHA Class 3 or Class 4, acute coronary syndrome, or persistent ventricular tachyarrhythmias)

• Patient has an unresolved Neisseria meningitidis infection

Excluded medications and therapies

• Current treatment with a complement inhibitor

• Intravenous immunoglobulin (IVIg) within 4 weeks prior to randomization on Day 1

Excluded prior/concurrent clinical study experience

• Treatment with investigational therapy in a clinical study within 30 days before randomization, or within 5 half-lives of that investigational therapy, whichever is greater

• Exceptions

a. Investigational therapies will be allowed if received as part of best supportive care through an expanded access protocol or emergency approval for the treatment of COVID-19.

b. Investigational antiviral therapies (such as remdesivir) will be allowed even if received as part of a clinical study.

Intervention and comparator

The study consists of a Screening Period of up to 3 days, a Primary Evaluation Period of 4 weeks, a final assessment at Day 29, and a Follow-up Period of 8 weeks. For patients randomized to ravulizumab plus BSC, a weight-based dose of ravulizumab (≥40 to < 60 kg/2400 mg, 60 to < 100 kg/2700 mg, ≥ 100 kg/3000 mg) will be administered on Day 1. On Day 5 and Day 10, additional doses of 600 mg (≥40 to <60 kg) or 900 mg (>60 kg) ravulizumab will be administered and on Day 15 patients will receive 900 mg ravulizumab. There is no active or placebo comparator in this open-label clinical trial. The total duration of each patient’s participation is anticipated to be approximately 3 months.

Main outcomes

The primary efficacy outcome of this study is survival (based on all-cause mortality) at Day 29.

Randomisation

Patients will be randomized in a 2:1 ratio (ravulizumab plus BSC:BSC alone). Randomization will be stratified by intubated or not intubated on Day 1. Computer-generated randomization lists will be prepared by a third party under the direction of the sponsor. Investigators, or designees, will enrol patients and then obtain randomization codes using an interactive voice/web response system. The block size will be kept concealed so that investigators cannot select patients for a particular treatment assignment.

Blinding (masking): This is an open-label study.

Numbers to be randomised (sample size): Approximately 270 patients will be randomly assigned in a 2:1 ratio to ravulizumab plus BSC (n=180) or BSC alone (n=90).

Trial status

Protocol Number: ALXN1210-COV-305

Original Protocol: 09 Apr 2020

Protocol Amendment 1 (Global): 13 Apr 2020

Protocol Amendment 2 (Global): 17 Apr 2020

Protocol Amendment 3 (Global): 09 Jun 2020

Recruitment is currently ongoing.

Recruitment was initiated on 11 May 2020.

We expect recruitment to be completed by 30 Nov 2020.

Trial registration

Clinicaltrials.gov: Protocol Registry Number: NCT04369469; First posted; 30 Apr 2020

EU Clinical Trials Register: EudraCT Number: https://www.clinicaltrialsregister.eu/ctr-search/search?query=ALXN1210-COV-305, Start date: 07 May 2020

Full protocol

The full redacted protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.

Pharmacokinetic and pharmacodynamic effects of ravulizumab and eculizumab on complement component 5 in adults with paroxysmal nocturnal haemoglobinuria: results of two phase 3 randomised, multicentre studies

Ravulizumab, a novel long‐acting complement component 5 (C5) inhibitor administered every 8 weeks (q8w), was non‐inferior to eculizumab for all efficacy outcomes in two randomised, open‐label, phase 3 trials in C5 inhibitor‐naïve (Study 301) and eculizumab‐experienced (Study 302) adult patients with paroxysmal nocturnal haemoglobinuria (PNH). This pre‐specified analysis characterised ravulizumab pharmacokinetics (PK), pharmacodynamics (PD; free C5 levels), and PD differences between medications (Study 301, n = 246; Study 302, n = 195). Ravulizumab PK parameters were determined using non‐compartmental analysis. Serum free C5 was quantified with a Gyros‐based fluorescence assay (ravulizumab) and an electrochemiluminescence ligand‐binding assay (eculizumab). Ravulizumab PK parameters were numerically comparable in both studies; the median time to maximum concentrations ranged from 2·3 to 2·8 and 2·3 to 2·6 h in studies 301 and 302, respectively. Ravulizumab steady‐state serum concentrations were achieved immediately after the first dose and sustained throughout treatment. For ravulizumab, the mean (SD) post hoc terminal elimination half‐life was 49·7 (8·9) days. Serum free C5 concentrations <0·5 µg/ml were achieved after the first ravulizumab dose and sustained throughout treatment in both studies. In a minority of patients, free C5 concentrations <0·5 µg/ml were not consistently achieved with eculizumab in either study. Ravulizumab q8w was more consistent in providing immediate, complete, sustained C5 inhibition than eculizumab every‐2‐weeks in patients with PNH.

Survivorship of wild caught Mepraia spinolai nymphs: The effect of seasonality and Trypanosoma cruzi infection after feeding and fasting in the laboratory

Chagas disease is caused by Trypanosoma cruzi. Vector survival is an important variable affecting vectorial capacity to determine parasite transmission risk. The aims of this study are to evaluate vector survival under fasting/starvation conditions of wild-caught Mepraia spinolai after feeding and fasting, the pathogenicity of T. cruzi infection, the parasite burden and seasonal variation in parasite discrete typing units (DTU). The survivorship of M. spinolai nymphs after two continuous artificial feedings was evaluated, assessing their infection with microscopic observation of fecal samples and PCR. Later, insects were fasted/starved until death. We performed qPCR analyses of parasite load in the fecal samples and dead specimens. T. cruzi genotyping was performed using conventional PCR amplicons and hybridization tests. Infection rate was higher in M. spinolai nymphs in summer and spring than in fall. Parasite burden varied from 3 to 250,000 parasites/drop. Survival rate for starved nymph stage II was lower in insects collected in the spring compared to summer and fall. TcII was the most frequent DTU. Mainly metacyclic trypomastigotes were excreted. We conclude that M. spinolai infection rate in nymphs varies among seasons, suggesting higher transmission risk in warmer seasons. However, nymphs stage II collected in spring are more sensitive to starvation compared to other seasons. TcII in single or mixed infection does not seem relevant to determine vector pathogenicity. These results of vector survivorship after fasting/starvation are important to determine the competence of M. spinolai as a vector of T. cruzi, since they excrete metacyclic trypomastigotes and the parasitism with T. cruzi seems to be poorly pathogenic to the vector under a severe fasting/starvation condition.

Comparison of clinical and cognitive characteristics of a Mexican adult clinical population with and without ADHD

Introduction. Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder affecting approximately 5% of the world population, with symptoms that may persist into adulthood. Despite the findings on the clinical course of this disorder, information regarding comorbidity patterns, psychosocial and executive functioning in adult life in those with and without ADHD in Latin American samples is scarce. Objective. The aim of this study is to compare the comorbidity pattern, psychosocial, and executive functioning of adults with and without ADHD from a clinical sample. Method. One hundred and fifty-one patients between 20 and 45 years, with screened positively on ASRS-V1.1, were invited to continue an evaluation process as part of clinical research program (PROMETEO): 1) K-SADS-PL Mx interview, 2) MINI-Plus interview, ASRS-V1-1 18 item version, BRIEF self-reported questionnaire, SCQA-ADHD, and 3) Individual case review by clinical expert in ADHD. Results. Individuals in the ADHD group had a higher average of comorbid disorders (2.5 SD 1.1 vs. 1.3 SD 1.0 respectively, F = .439; t = -6.621; df = 149; p < .001), more likelihood of procrastinating (OR = 6.5; 95% CI[2.6, 16.2]; z = 4.0) and were more likely to present difficulties in both the behavior regulation index (OR = 104.9; 95% CI[31.8, 345.7]; z = 7.65) and the metacognitive index (OR = 94.79; 95% CI[29.10, 308.76]; z = 7.56) compared to the non-ADHD group, regardless of gender. Discussion and conclusions. Our results indicate that the ADHD adult group presented with more comorbidity, and worse psychosocial and executive functioning than non-ADHD adults.

Minicircle classes heterogeneity within the TcIII and TcIV discrete typing units of Trypanosoma cruzi

The taxon Trypanosoma cruzi, causative agent of Chagas disease, is composed of several discrete typing units (DTUs) named TcI-TcVI, and Tcbat. The history of the taxon T. cruzi is known, even though several controversial aspects remain as the relationships between TcIII and TcIV. We analyzed cloned T. cruzi stocks pertaining to the seven DTUs by filter hybridization tests of PCR amplicons from minicircle variable regions and kinetoplast DNA probes. Minicircle DNA blots from the cloned stocks and filter hybridization with one TcI, one TcII, one TcV, one TcVI, three TcIII, one TcIV from North America and one TcIV kinetoplast DNA probes from South America revealed minicircle variable region cross-reaction in some T. cruzi DTUs probed. TcIII was heterogeneous in minicircle class composition, even though two TcIII probes revealed that a small fraction of minicircles cross-hybridized with the minicircles from the TcIII, TcV and TcVI DTUs. The minicircles of TcIV from North America cross-reacted only with TcIV from North America but not with TcIV stocks from Brazil and Bolivia. The results on minicircle cross-hybridizations are discussed in the context of RNA editing, mitochondrial function in T. cruzi DTUs.

[Prognostic implications of folliculo-stellate cells in pituitary adenomas: relationship with tumoral behavior]

INTRODUCTION

Despite progress in understanding its pathogenesis, there has not yet been found any independent predictive marker of aggressive behavior of pituitary adenomas, to facilitate the treatment and monitoring of patients.

AIM

To analyze the expression of folliculo-stellate cells by immunostaining with S-100 protein, in a series of patients with pituitary adenomas followed for at least seven years.

PATIENTS AND METHODS

A retrospective study of 51 patients diagnosed with a pituitary adenoma between 2006 and 2008 was performed, according to current criteria established by the World Health Organization. The S-100 expression in folliculo-stellate cells was immunohistochemically evaluated, correlating it with clinico-radiological and histopathological tumor parameters and post-operative progression/recurrence.

RESULTS

Of 51 tumors, 40 were classified as typical and 11 as atypical pituitary adenomas. Most typical pituitary adenomas showed positive folliculo-stellate cells for S-100 (mean: 3.93%); atypical had little/no cell S-100 positive (mean: 0.83%). There were no significant differences in the expression of S-100 with respect to age or sex of the patient, size, invasiveness or post-operative tumor recurrence.

CONCLUSIONS

In our study group, with the exception of non-functioning adenomas immunopositive for prolactin, with the lowest and highest average of all subtypes in both groups (typical 0.25% vs atypical 9.24%; p = 0.0028), the predictive factor of tumor aggressiveness for pituitary adenomas, is not represented by a low value of S-100 in folliculo-stellate cells, not allowing select patients for intensive post-operative treatment.

Trypanosoma cruzi diversity in infected dogs from areas of the north coast of Chile

As part of a multi-site research program on the eco-epidemiology and control of Chagas disease in northern Chile, we sought to identify the Trypanosoma cruzi discrete typing units (DTUs) infecting rural and peridomestic dogs, using direct methods without grown of the parasite in the laboratory and thus to assess the use of this species as a sentinel of the disease in well-defined endemic areas of T. cruzi in Chile. Infected dogs (35) from three villages were included in the study. The studied villages were Caleta Río Seco and Caleta San Marcos, both in the Tarapacá Region, and La Serena in the Coquimbo Region. These villages were selected based on previous evidence of Mepraia infection reports of the Chilean Ministry of Health. Amplicons from nested-PCR positive samples were used as targets to determine the infective T. cruzi DTUs circulating in blood using PCR-DNA blotting and hybridization assays with five specific DNA probes (TcI, TcII, TcIII, TcV and TcVI). Results of hybridization with dog samples from Caleta Rio Seco showed single infections in 2 out of 16 and mixed infections in 14 out of 16. TcVI was the most frequent DTU found in this area. A highlight is that for the first time the presence of TcIII is reported in this area. Samples from Caleta San Marcos showed single infections in 5 out of 9 and mixed infections in 4 out of 9. TcVI was the most frequent DTU found in this area. Samples from La Serena showed single infections in 5 out of 10 and mixed infections in 2 out of 10; we were unable to genotype the other 3 samples. Our results indicate that infection by T. cruzi DTUs in dogs is not homogeneously distributed but rather specific to each region of our country, as demonstrated by the differences in the T. cruzi DTU distribution in some localities.

Birth Control and Low-Income Mexican-American Women: The Impact of Three Values

Nineth-nine Mexican-American women who were identified as either high or low acculturated responded to questionnaires assessing the relationship between birth control attitudes, knowledge, and usage, and the values ascribed to motherhood, male dominance, and sexual expression. Using a multiple regression analysis, a significant positive relationship was found for both high and low acculturated women with respect to their attitudes toward birth control and the values ascribed to motherhood, male dominance, and sexual expression. Relative to birth control use, a significant positive relationship was found between this variable and the values ascribed to motherhood, male dominance, and sexual expression for the low but ntot the high acculturated women. Finallh, no significant relationship was found between birth control knowledge and the aforementioned values. It should be noted that the differences between the low and high acculturated women persisted even while holding their socioeconomic level constant.

Mid-infrared nonlinear optical response of Si-Ge waveguides with ultra-short optical pulses

We characterize the nonlinear optical response of low loss Si(0.6)Ge(0.4) / Si waveguides in the mid-infrared between 3.3 μm and 4 μm using femtosecond optical pulses. We estimate the three and four-photon absorption coefficients as well as the Kerr nonlinear refractive index from the experimental measurements. The effect of multiphoton absorption on the optical nonlinear Kerr response is evaluated and the nonlinear figure of merit estimated providing some guidelines for designing nonlinear optical devices in the mid-IR. Finally, we compare the impact of free-carrier absorption at mid-infrared wavelengths versus near-infrared wavelengths for these ultra-short pulses.

On the prediction of Hodgkin lymphoma treatment response

PURPOSE

The cure rate in Hodgkin lymphoma is high, but the response along with treatment is still unpredictable and highly variable among patients. Detecting those patients who do not respond to treatment at early stages could bring improvements in their treatment. This research tries to identify the main biological prognostic variables currently gathered at diagnosis and design a simple machine learning methodology to help physicians improve the treatment response assessment.

METHODS

We carried out a retrospective analysis of the response to treatment of a cohort of 263 Caucasians who were diagnosed with Hodgkin lymphoma in Asturias (Spain). For that purpose, we used a list of 35 clinical and biological variables that are currently measured at diagnosis before any treatment begins. To establish the list of most discriminatory prognostic variables for treatment response, we designed a machine learning approach based on two different feature selection methods (Fisher's ratio and maximum percentile distance) and backwards recursive feature elimination using a nearest-neighbor classifier (k-NN). The weights of the k-NN classifier were optimized using different terms of the confusion matrix (true- and false-positive rates) to minimize risk in the decisions.

RESULTS AND CONCLUSIONS

We found that the optimum strategy to predict treatment response in Hodgkin lymphoma consists in solving two different binary classification problems, discriminating first if the patient is in progressive disease; if not, then discerning among complete and partial remission. Serum ferritin turned to be the most discriminatory variable in predicting treatment response, followed by alanine aminotransferase and alkaline phosphatase. The importance of these prognostic variables suggests a close relationship between inflammation, iron overload, liver damage and the extension of the disease.

Nonlinear optical response of low loss silicon germanium waveguides in the mid-infrared

We have investigated the nonlinear optical response of low loss Si(0.6)Ge(0.4) / Si waveguides in the mid-infrared wavelength range from 3.25- 4.75μm using picosecond optical pulses. We observed and measured the three and four-photon absorption coefficients as well as the Kerr nonlinear refractive index. The dynamics of the spectral broadening suggests that, in addition to multiphoton absorption, the corresponding higher order nonlinear refractive phenomena also needs to be included when high optical pulse intensities are used at mid-infrared wavelengths in this material.

FT-IR and FT-Raman spectra of 6-chlorouracil: molecular structure, tautomerism and solid state simulation. A comparison between 5-chlorouracil and 6-chlorouracil

A Raman and IR study of the biomolecule 6-chlorouracil was carried out in the solid state. The unit cell found in the crystal was simulated as a tetramer form by density functional calculations. Specific scale factors and scaling equations deduced from uracil molecule were employed in the predicted wavenumbers of 6-chlorouracil. The scaled wavenumbers were used in the reassignment of the IR and Raman experimental bands. Good reproduction of the experimental wavenumbers is obtained and the % error is very small in the majority of cases. A comparison between the molecular structure and charge distribution of 6-chlorouracil and 5-chlorouracil molecules was presented. The effect of the hydration with the PCM model in the molecular structure and charges was discussed. The optimum tautomers of 6-chlorouracil were optimized and analyzed. Six of them were related to those of uracil molecule. The effect of the halogen substitution in the sixth position of the pyrimidine ring in the stability of the different tautomers was evaluated. HOMO and LUMO orbital energy analysis were carried out.

Abstract 633: Pharmacodynamic Interactions Between Nebivolol and Valsartan in Healthy Volunteers

Background: Combining different classes of antihypertensive drugs is more effective for achieving blood pressure (BP) control than increasing the dose of monotherapies. An aim of this study was to investigate pharmacodynamic (PD) interactions between nebivolol, a β1 selective, vasodilatory beta blocker and valsartan, an angiotensin II type 1 receptor blocker.

Methods: This was a single-center, randomized, open-label, multiple-dose, three-way crossover trial in 30 healthy adults aged 18-45 years. Participants were randomized into one of six treatment sequences (1:1:1:1:1:1) consisting of three 7-day treatment periods followed by a 7-day washout. Once-daily oral treatments comprised nebivolol 20 mg, valsartan 320 mg, or nebivolol 20 mg plus valsartan 320 mg. Outcomes included changes in BP, heart rate (HR), plasma angiotensin II, plasma renin activity (PRA), and 24-hour urinary aldosterone.

Results: The drop in least square mean values of systolic and diastolic BP was significantly greater following the concomitant administration of nebivolol and valsartan than either monotherapy alone. The mean HR after treatment with nebivolol alone, as well as after the combined treatment, was consistently lower than valsartan monotherapy. A sharp increase in mean Day 7 PRA and plasma angiotensin II occurred in subjects receiving valsartan alone and this was significantly attenuated with concomitant nebivolol administration. Mean 24-hour urine aldosterone at Day 7 was substantially decreased after combined treatment, as compared to either monotherapy treatment. All treatments were safe and well tolerated.

Conclusion: Nebivolol and valsartan co-administration led to greater reductions in BP compared to either monotherapy. Nebivolol attenuated valsartan-induced increases in angiotensin II levels and PRA and reduced urinary aldosterone levels. Hence, these mechanisms for BP lowering are complementary and provide a rationale for further investigation of this combination in patients with essential hypertension.

Common variant in VEGFA and response to anti-VEGF therapy for neovascular age-related macular degeneration

Age-related macular degeneration (AMD) is a leading cause of visual impairment in aging populations in industrialized countries. Here we investigated whether the genotype of vascular endothelial growth factor A (VEGFA) gene is associated with response to anti-VEGF therapy. 223 eyes with neovascular AMD were treated with intravitreal anti-VEGF therapy. Responders were defined as patients who had an improvement in best corrected visual acuity (BCVA) of at least 5 letters or one line on the EDTRS visual acuity chart along with resolution of intraretinal or subretinal fluid over 12 months. Patients who did not meet the definition of responders were classified as poor-responders. The vision of responders (n = 148) improved while the vision of poor-responders (n = 75) worsened (P<0.001). Responders on average had a decrease in central foveal thickness (CFT), while poor-responders had an increase in CFT (P <0.001). Compared with the responder group, the poor-responder group had a higher frequency of the risk (T) allele (Allelic P = 0.019) and TT genotype (P = 0.002 under a recessive model) for the VEGFA-rs943080 polymorphism. VEGFA expression was 1.8-fold higher in cells with the VEGFA rs943080 TT genotype than in cells with the VEGFA rs943080 CC genotype (P = 0.012). Age, gender, smoking, diabetes mellitus, and hypertension did not play a significant role in treatment response, but BMI was found to be significantly different between responders and poorresponders (P = 0.033). In conclusion, we demonstrated a potential pharmacogenetic relationship between the VEGFA gene and treatment response to anti-VEGF therapy.The studies are registered at ClinicalTrials.gov under the identifiers NCT00474695 (http://clinicaltrials. gov/ct2/show/NCT00474695) and NCT01464723 (http://clinicaltrials.gov/ct2/show/NCT01464723).