CEA-CD3 bispecific antibody cibisatamab with or without atezolizumab in patients with CEA-positive solid tumours: results of two multi-institutional Phase 1 trials.

Cibisatamab is a bispecific antibody-based construct targeting carcinoembryonic antigen (CEA) on tumour cells and CD3 epsilon chain as a T-cell engager. Here we evaluated cibisatamab for advanced CEA-positive solid tumours in two open-label Phase 1 dose-escalation and -expansion studies: as a single agent with or without obinutuzumab in S1 (NCT02324257) and with atezolizumab in S2 (NCT02650713). Primary endpoints were safety, dose finding, and pharmacokinetics in S1; safety and dose finding in S2. Secondary endpoints were anti-tumour activity (including overall response rate, ORR) and pharmacodynamics in S1; anti-tumour activity, pharmacodynamics and pharmacokinetics in S2. S1 and S2 enrolled a total of 149 and 228 patients, respectively. Grade ≥3 cibisatamab-related adverse events occurred in 36% of S1 and 49% of S2 patients. The ORR was 4% in S1 and 7% in S2. In S2, patients with microsatellite stable colorectal carcinoma (MSS-CRC) given flat doses of cibisatamab and atezolizumab demonstrated an ORR of 14%. In S1 and S2, 40% and 52% of patients, respectively, developed persistent anti-drug antibodies (ADAs). ADA appearance could be mitigated by obinutuzumab-pretreatment, with 8% of patients having persistent ADAs. Overall, cibisatamab warrants further exploration in immunotherapy combination strategies for MSS-CRC.

Advancing drug development in pediatric oncology, a focus on cancer biology and targeted therapies: iMATRIX platform.

With the development of novel treatment therapies as well as evolving and innovative approaches to conduct clinical trials, the landscape of pediatric oncology drug development has dramatically changed in recent years. Despite this change, approvals for new drugs and labeling updates to ensure availability of proper treatment for pediatric patients with cancer remain slow. The context of drug development in pediatric tumors has also changed with regulatory initiatives in the US and Europe, creating a great need for faster development of novel drugs. Today, conventional study designs have been replaced or complemented by novel clinical trial designs, such as master protocols and platform trials, to optimize cancer drug development and enable faster regulatory approval. The iMATRIX platform is a mechanism-of-action (MOA)-based phase 1/2 trial framework for concurrently studying multiple molecules across a range of relevant pediatric tumor types, taking into account the biology of each pediatric tumor type. Six studies have been conducted, ongoing, or planned on the iMATRIX platform - investigating atezolizumab, cobimetinib, entrectinib, idasanutlin, alectinib, and glofitamab. A brief overview of study designs and characteristics are shared in this article, along with learnings from them.

Metastatic Rhabdomyosarcoma: Results of the European Paediatric Soft Tissue Sarcoma Study Group MTS 2008 Study and Pooled Analysis With the Concurrent BERNIE Study.

PURPOSE: Outcome for patients with metastatic rhabdomyosarcoma (RMS) is poor. This study presents the results of the MTS 2008 study with a pooled analysis including patients from the concurrent BERNIE study. PATIENTS AND METHODS: In MTS 2008, patients with metastatic RMS received four cycles of ifosfamide, vincristine, and actinomycin D (IVA) plus doxorubicin, five cycles of IVA, and 12 cycles of maintenance chemotherapy (low-dose cyclophosphamide and vinorelbine). The BERNIE study randomly assigned patients to the addition or not of bevacizumab to the same chemotherapy. Local therapy (surgery/radiotherapy) was given to the primary tumor and all metastatic sites when feasible. RESULTS: MTS 2008 included 270 patients (median age, 9.6 years; range, 0.07-20.8 years). With a median follow-up of 50.3 months, 3-year event-free survival (EFS) and overall survival (OS) were 34.9% (95% CI, 29.1 to 40.8) and 47.9% (95% CI, 41.6 to 53.9), respectively. In pooled analyses on 372 patients with a median follow-up of 55.2 months, 3-year EFS and OS were 35.5% (95% CI, 30.4 to 40.6) and 49.3% (95% CI, 43.9 to 54.5), respectively. Patients with ≤ 2 Oberlin risk factors (ORFs) had better outcome than those with ≥ 3 ORFs: 3-year EFS was 46.1% versus 12.5% (P < .0001) and 3-year OS 60.0% versus 26.0% (P < .0001). Induction chemotherapy and maintenance appeared tolerable; however, about two third of patients needed dose adjustments during maintenance. CONCLUSION: Outcome remains poor for patients with metastatic RMS and multiple ORFs. Because of the design of the studies, it was not possible to determine whether the intensive induction regimen and/or the addition of maintenance treatment resulted in apparent improvement of outcome compared with historical cohorts. Further studies, with novel treatment approaches are urgently needed, to improve outcome for the group of patients with adverse prognostic factors.

Extension of the Alternative Intravenous Dosing Regimens of Atezolizumab into Combination Settings through Modeling and Simulation.

Atezolizumab is approved as an intravenous (IV) infusion for use as a single agent and in combination with other therapies in a number of indications. The objectives of this publication are to characterize atezolizumab pharmacokinetics (PK) across indications with the available clinical data from one phase I and eight phase III studies, to determine the exposure-response (ER) relationships in combination settings across a variety of tumor types, and to provide the clinical safety to support the extension of the 840 mg q2w, 1200 mg q3w, and 1680 mg q4w IV dosing regimens across various indications in combination settings. Across all clinical studies, atezolizumab PK remained in the dose-linear range and were similar across tumor types when used in combination therapy or as a monotherapy. In the combination studies, efficacy was independent of the exposures tested and there was no significant increase in adverse events with increasing atezolizumab exposure (flat ER). The safety profile of atezolizumab in the individual combination studies was generally consistent with the established safety profile of atezolizumab, the combination partners, and the disease under study. The similar atezolizumab PK across monotherapy and combination therapy settings as well as the flat ER in new tumor types and combination therapies support the use of the 3 interchangeable atezolizumab dosing regimens in the combination setting. Atezolizumab is now approved with 3 interchangeable IV dosing regimens of 840 mg q2w, 1200 mg q3w, and 1680 mg q4w for single-agent and combination therapy use in the USA and EU.

The Impact of Radiation Therapy in Children and Adolescents With Metastatic Rhabdomyosarcoma.

PURPOSE: There is limited evidence to define the role of radiation therapy in children with metastatic rhabdomyosarcoma (mRMS). In the international BERNIE study, children with mRMS or non-RMS soft tissue sarcoma were randomized to receive standard chemotherapy with or without bevacizumab, with radiation therapy to all disease sites recommended after chemotherapy cycle 6. We retrospectively evaluated the impact of radiation therapy on survival in the mRMS cohort. METHODS AND MATERIALS: Patients were grouped according to the radiation therapy they received: radical, partial, or none. Radical irradiation was defined as radiation therapy delivered to all disease sites, unless a site was completely surgically resected. Partial irradiation was defined as radiation therapy to ≥1, but not all, disease sites. Landmark analysis excluded patients with an event before day 221. Overall survival (OS) and event-free survival (EFS) were modeled using Cox proportional hazards models. RESULTS: Of 102 patients with mRMS, 97 were included in the analysis for OS and 85 for EFS. Overall, 27 patients received radical irradiation, 46 partial irradiation, and 24 no irradiation. EFS was not significantly different among patient groups after adjustment for prognostic factors (hazard ratio [HR] = 0.520; P = .054 for any vs no irradiation). Radiation therapy was associated with improved OS compared with no radiation therapy (adjusted HR = 0.249; P = .00025), with OS being greater for radical versus partial irradiation (HR = 0.245; P = .039). The 3-year OS rate was 84%, 54%, and 23% for patients receiving radical, partial, and no irradiation, respectively. Radical treatment (surgery, irradiation, or both) of the primary site improved EFS and OS compared with no treatment. CONCLUSIONS: These findings demonstrate variability in the application of radiation therapy for mRMS and support the routine use of radical treatment to the primary site. Radical irradiation to metastatic sites may further improve OS. The burden of such treatment should be balanced against prognosis; further studies are needed.

Gross motor function outcomes following deep brain stimulation for childhood-onset dystonia: A descriptive report.

AIM: To examine the impact of deep brain stimulation (DBS) on gross motor function in children with dystonic movement disorders. METHOD: Prospective audit involving children implanted 2007-2015, followed for up to two years. Outcomes were evaluated across aetiological sub-groups (inherited, acquired, idiopathic) using the GMFM-88 and BFMDRS movement scale (BFM-M). The predictive value of proportion of life lived with dystonia (PLD) and baseline motor capacity were evaluated. RESULTS: Data was available for 60 children (median surgery age 10y11mo). Inherited monogenetic dystonias demonstrated a median increase in GMFM-88 scores of 6.9% (p = 0.021) and 14.5% (p = 0.116) at one and two years. Heredodegenerative and idiopathic dystonias showed disparate responses, with non-significant changes seen in GMFM-88 and BFM-M scores, with the exception of improved one-year BFM-M scores in the idiopathic group [median change 5.5, p = 0.021]. Median GMFM-88 and BFM-M change scores were near zero for acquired dystonias, though improvement was noted in 9/18 CP cases with one-year GMFM-88 data. No significant relationship was found between PLD, or baseline GMFM-88, and GMFM-88 change following DBS. CONCLUSION: Gross motor response to DBS is similar in profile to literature reporting results using impairment-based dystonia rating scales. Relatively consistent improvements were seen in inherited monogenetic ("primary") dystonias, while highly variable, often disappointing, gross motor responses were found in acquired, heredodegenerative, and idiopathic dystonias. In view of such response variability, alternatives to mean group studies, such as single case experimental designs with multiple replications, are needed to determine the efficacy of DBS in childhood-onset dystonias. Ongoing research is needed to identify factors that predict treatment response.

Integrated analysis of long-term growth and bone development in pediatric and adolescent patients receiving bevacizumab.

BACKGROUND: We conducted an integrated analysis of clinical data to describe long-term effects of bevacizumab on growth and bone development in pediatric and adolescent patients with solid tumors. PROCEDURE: Clinical data were pooled from five phase I/II trials of bevacizumab versus chemotherapy: BERNIE, HERBY, and AVF4117s enrolled newly diagnosed patients, AVF3842s and AVF2771s enrolled patients with relapsed/refractory disease. Height, weight, body mass index (BMI), and bone-age data were pooled by treatment group. Growth charts were used to track and monitor growth in relation to a reference population of healthy children. Bone age was measured based on X-ray of the left hand and wrist. Analyses were exploratory/descriptive. RESULTS: Overall, 268 patients received bevacizumab ± chemotherapy and 135 received chemotherapy alone. Baseline characteristics were generally balanced. Median duration of long-term follow-up was 41.8 months (range, 2.4-75.1) with bevacizumab and 22.9 months (range, 2.8-69.2) with chemotherapy alone. Patients had age-appropriate baseline height and weight. Mean height and weight percentiles decreased over time in both treatment groups, but remained within the normal range (height: mean standard deviation score [SDS] range -2 to +3; weight: mean SDS range -2 to +1). Similar trends were seen in BMI. A tendency for reduced growth velocity relative to the reference population was observed at 6 months and 1 year in both groups, but there was no additional decrease for patients receiving bevacizumab. CONCLUSION: Bevacizumab did not appear to have additional negative effects on growth or development of pediatric and adolescent patients with solid tumors.

Phase II, Open-Label, Randomized, Multicenter Trial (HERBY) of Bevacizumab in Pediatric Patients With Newly Diagnosed High-Grade Glioma.

Purpose Bevacizumab (BEV) is approved in more than 60 countries for use in adults with recurrent glioblastoma. We evaluated the addition of BEV to radiotherapy plus temozolomide (RT+TMZ) in pediatric patients with newly diagnosed high-grade glioma (HGG). Methods The randomized, parallel group, multicenter, open-label HERBY trial ( ClinicalTrials.gov identifier: NCT01390948) enrolled patients age ≥ 3 years to ≤ 18 years with localized, centrally neuropathology-confirmed, nonbrainstem HGG. Eligible patients were randomly assigned to receive RT + TMZ (RT: 1.8 Gy, 5 days per week, and TMZ: 75 mg/m2 per day for 6 weeks; 4-week treatment break; then up to 12 × 28-day cycles of TMZ [cycle 1: 150 mg/m2 per day, days 1 to 5; cycles 2 to 12: 200 mg/m2 per day, days 1 to 5]) with or without BEV (10 mg/kg every 2 weeks). The primary end point was event-free survival (EFS) as assessed by a central radiology review committee that was blinded to treatment. We report findings of EFS at 12 months after the enrollment of the last patient. Results One hundred twenty-one patients were enrolled (RT+TMZ [n = 59]; BEV plus RT+TMZ [n = 62]). Central radiology review committee-assessed median EFS did not differ significantly between treatment groups (RT+TMZ, 11.8 months; 95% CI, 7.9 to 16.4 months; BEV plus RT+TMZ, 8.2 months; 95% CI, 7.8 to 12.7 months; hazard ratio, 1.44; P = .13 [stratified log-rank test]). In the overall survival analysis, the addition of BEV did not reduce the risk of death (hazard ratio, 1.23; 95% CI, 0.72 to 2.09). More patients in the BEV plus RT+TMZ group versus the RT+TMZ group experienced one or more serious adverse events (n = 35 [58%] v n = 27 [48%]), and more patients who received BEV discontinued study treatment as a result of adverse events (n = 13 [22%] v n = 3 [5%]). Conclusion Adding BEV to RT+TMZ did not improve EFS in pediatric patients with newly diagnosed HGG. Our findings were not comparable to those of previous adult trials, which highlights the importance of performing pediatric-specific studies.

Somatosensory Evoked Potentials and Central Motor Conduction Times in children with dystonia and their correlation with outcomes from Deep Brain Stimulation of the Globus pallidus internus.

OBJECTIVES: To report Somatosensory Evoked Potentials (SEPs) and Central Motor Conduction Times (CMCT) in children with dystonia and to test the hypothesis that these parameters predict outcome from Deep Brain Stimulation (DBS). METHODS: 180 children with dystonia underwent assessment for Globus pallidus internus (GPi) DBS, mean age 10 years (range 2.5-19). CMCT to each limb was calculated using Transcranial Magnetic Stimulation. Median and posterior tibial nerve SEPs were recorded over contralateral and midline centro-parietal scalp. Structural abnormalities were assessed with cranial MRI. One-year outcome from DBS was assessed as percentage improvement in Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS-m). RESULTS: Abnormal CMCTs and SEPs were found in 19% and 47% of children respectively and were observed more frequently in secondary than primary dystonia. Of children proceeding to DBS, better outcome was seen in those with normal (n = 78/89) versus abnormal CMCT (n = 11/89) (p = 0.002) and those with normal (n = 35/51) versus abnormal SEPs (n = 16/51) (p = 0.001). These relationships were independent of dystonia aetiology and cranial MRI findings. CONCLUSIONS: CMCTs and SEPs provide objective evidence of motor and sensory pathway dysfunction in children with dystonia and relate to DBS outcome. SIGNIFICANCE: CMCTs and SEPs can contribute to patient selection and counselling of families about potential benefit from neuromodulation for dystonia.

Comparison of Propensity Score Methods and Covariate Adjustment: Evaluation in 4 Cardiovascular Studies.

Propensity scores (PS) are an increasingly popular method to adjust for confounding in observational studies. Propensity score methods have theoretical advantages over conventional covariate adjustment, but their relative performance in real-word scenarios is poorly characterized. We used datasets from 4 large-scale cardiovascular observational studies (PROMETHEUS, ADAPT-DES [the Assessment of Dual AntiPlatelet Therapy with Drug-Eluting Stents], THIN [The Health Improvement Network], and CHARM [Candesartan in Heart Failure-Assessment of Reduction in Mortality and Morbidity]) to compare the performance of conventional covariate adjustment with 4 common PS methods: matching, stratification, inverse probability weighting, and use of PS as a covariate. We found that stratification performed poorly with few outcome events, and inverse probability weighting gave imprecise estimates of treatment effect and undue influence to a small number of observations when substantial confounding was present. Covariate adjustment and matching performed well in all of our examples, although matching tended to give less precise estimates in some cases. PS methods are not necessarily superior to conventional covariate adjustment, and care should be taken to select the most suitable method.

Failing to progress or progressing to fail? Age-for-grade heterogeneity and grade repetition in primary schools in Karonga district, northern Malawi.

Timely progression through school is an important measure for school performance, completion and the onset of other life transitions for adolescents. This study examines the risk factors for grade repetition and establishes the extent to which age-for-grade heterogeneity contributes to subsequent grade repetition at early and later stages of school. Using data from a demographic surveillance site in Karonga district, northern Malawi, a cohort of 8174 respondents (ages 5-24 years) in primary school was followed in 2010 and subsequent grade repetition observed in 2011. Grade repetition was more common among those at early (grades 1-3) and later (grades 7-8) stages of school, with little variation by sex. Being under-age or over-age in school has different implications on schooling outcomes, depending on the stage of schooling. After adjusting for other risk factors, boys and girls who were under-age at early stages were at least twice as likely to repeat a grade as those at the official age-for-grade (girls: adjusted OR 2.06 p < 0.01; boys: adjusted OR 2.37 p < 0.01); while those over-age at early stages were about 30% less likely to repeat (girls: adjusted OR 0.65 p < 0.01; boys: adjusted OR 0.72 p < 0.01). Being under/over-age at later grades (4-8) was not associated with subsequent repetition but being over-age was associated with dropout. Other risk factors identified that were associated with repetition included both family-level factors (living away from their mother, having young children in the household, lower paternal education) and school-level factors (higher student-teacher ratio, proportion of female teachers and schools without access to water). Reducing direct and indirect costs of schooling for households; and improving school quality and resources at early stages of school may enable timely progression at early stages for greater retention at later stages.

Progression to musculoskeletal deformity in childhood dystonia.

AIM: Dystonia is a movement disorder characterized by involuntary muscle contractions, resulting in abnormalities of posture and movement. Children with dystonia are at risk of developing fixed musculoskeletal deformities (FMDs). FMDs cause pain, limit function and participation and interfere with care. We aimed to explore factors relating to the development of FMD in a large cohort of children with dystonia. METHOD: The case notes of all children referred to our Complex Motor Disorder service between July 2005 and December 2011 were reviewed. Data from 279 children (median age 9 years 10 months, Standard Deviation 4 years 2 months) with motor disorders including a prominent dystonic element were analyzed. Parametric accelerated failure time regression was used to identify the factors related to development of contractures. RESULTS: FMDs were present at referral in more than half (n = 163, 58%) of cases. Three quarters (n = 120, 74%) of children with FMD had deformities around the hip, and 42% had spinal deformity (n = 68). Compared to pure primary dystonia, FMD onset was earlier with a diagnosis of secondary or heredodegenerative dystonia, and a mixed spastic-dystonic phenotype (all p < 0.001). FMD onset was also earlier with increasing Gross Motor Function Classification System (GMFCS) level (p < 0.001). The effect of aetiological classification was lost when controlling for GMFCS level and motor phenotype. INTERPRETATION: Children with secondary or heredodegenerative dystonia are at greater risk of progression to FMD compared to primary dystonia, likely due to more severe dystonia within these groups. Children with additional spasticity are at particular risk, requiring close monitoring.

Burke-Fahn-Marsden dystonia severity, Gross Motor, Manual Ability, and Communication Function Classification scales in childhood hyperkinetic movement disorders including cerebral palsy: a 'Rosetta Stone' study.

AIM: Hyperkinetic movement disorders (HMDs) can be assessed using impairment-based scales or functional classifications. The Burke-Fahn-Marsden Dystonia Rating Scale-movement (BFM-M) evaluates dystonia impairment, but may not reflect functional ability. The Gross Motor Function Classification System (GMFCS), Manual Ability Classification System (MACS), and Communication Function Classification System (CFCS) are widely used in the literature on cerebral palsy to classify functional ability, but not in childhood movement disorders. We explore the concordance of these three functional scales in a large sample of paediatric HMDs and the impact of dystonia severity on these scales. METHOD: Children with HMDs (n=161; median age 10y 3mo, range 2y 6mo-21y) were assessed using the BFM-M, GMFCS, MACS, and CFCS from 2007 to 2013. This cross-sectional study contrasts the information provided by these scales. RESULTS: All four scales were strongly associated (all Spearman's rank correlation coefficient rs >0.72, p<0.001), with worse dystonia severity implying worse function. Secondary dystonias had worse dystonia and less function than primary dystonias (p<0.001). A longer proportion of life lived with dystonia is associated with more severe dystonia (rs =0.42, p<0.001). INTERPRETATION: The BFM-M is strongly linked with the GMFCS, MACS, and CFCS, irrespective of aetiology. Each scale offers interrelated but complementary information and is applicable to all aetiologies. Movement disorders including cerebral palsy can be effectively evaluated using these scales.

Retrospective review of the drop in observer detection performance over time in lesion-enriched experimental studies.

The vigilance decrement describes a decrease in sensitivity or increase in specificity with time on task. It has been observed in a variety of repetitive visual tasks, but little is known about these patterns in radiologists. We investigated whether there is systematic variation in performance over the course of a radiology reading session. We re-analyzed data from six previous lesion-enriched radiology studies. Studies featured 8-22 participants assessing 27-100 cases (including mammograms, chest CT, chest x-ray, and bone x-ray) in a reading session. Changes in performance and speed as the reading session progressed were analyzed using mixed effects models. Time taken per case decreased 9-23% as the reading session progressed (p < 0.005 for every study). There was a sensitivity decrease or specificity increase over the course of reading 100 chest x-rays (p = 0.005), 60 bone fracture x-rays (p = 0.03), and 100 chest CT scans (p < 0.0001). This effect was not found in the shorter mammography sessions with 27 or 50 cases. We found evidence supporting the hypothesis that behavior and performance may change over the course of reading an enriched test set. Further research is required to ascertain whether this effect is present in radiological practice.

Wellington: a novel method for the accurate identification of digital genomic footprints from DNase-seq data.

The expression of eukaryotic genes is regulated by cis-regulatory elements such as promoters and enhancers, which bind sequence-specific DNA-binding proteins. One of the great challenges in the gene regulation field is to characterise these elements. This involves the identification of transcription factor (TF) binding sites within regulatory elements that are occupied in a defined regulatory context. Digestion with DNase and the subsequent analysis of regions protected from cleavage (DNase footprinting) has for many years been used to identify specific binding sites occupied by TFs at individual cis-elements with high resolution. This methodology has recently been adapted for high-throughput sequencing (DNase-seq). In this study, we describe an imbalance in the DNA strand-specific alignment information of DNase-seq data surrounding protein-DNA interactions that allows accurate prediction of occupied TF binding sites. Our study introduces a novel algorithm, Wellington, which considers the imbalance in this strand-specific information to efficiently identify DNA footprints. This algorithm significantly enhances specificity by reducing the proportion of false positives and requires significantly fewer predictions than previously reported methods to recapitulate an equal amount of ChIP-seq data. We also provide an open-source software package, pyDNase, which implements the Wellington algorithm to interface with DNase-seq data and expedite analyses.

Selective phenotyping, entropy reduction, and the mastermind game.

BACKGROUND: With the advance of genome sequencing technologies, phenotyping, rather than genotyping, is becoming the most expensive task when mapping genetic traits. The need for efficient selective phenotyping strategies, i.e. methods to select a subset of genotyped individuals for phenotyping, therefore increases. Current methods have focused either on improving the detection of causative genetic variants or their precise genomic location separately. RESULTS: Here we recognize selective phenotyping as a Bayesian model discrimination problem and introduce SPARE (Selective Phenotyping Approach by Reduction of Entropy). Unlike previous methods, SPARE can integrate the information of previously phenotyped individuals, thereby enabling an efficient incremental strategy. The effective performance of SPARE is demonstrated on simulated data as well as on an experimental yeast dataset. CONCLUSIONS: Using entropy reduction as an objective criterion gives a natural way to tackle both issues of detection and localization simultaneously and to integrate intermediate phenotypic data. We foresee entropy-based strategies as a fruitful research direction for selective phenotyping.