P02.05.B Targeted therapies of Glioblastoma using single cell sequencing and drug-response analysis in a phase 2 clinical trial setting

Background

Glioblastoma is an aggressive brain tumour with a median survival of less than 15 months despite aggressive standard treatment consisting of neurosurgery, radiotherapy plus concomitant and adjuvant chemotherapy with temozolomide. There is no standard treatment at recurrence, and all have limited efficacy. In this study we will enroll glioblastoma patients from the Danish clinical trial “Protarget” to get a better understanding of resistance mechanisms and vulnerabilities in glioblastoma to give personalized medicine to glioblastoma patients at recurrent disease. We hypothesise that two connected factors are responsible for the failure to successfully target glioblastoma: i) intra-tumour heterogeneity and within this ii) cancer stem cells.

Material and Methods

We will use tumour tissue from glioblastoma patients included in the Danish phase 2, prospective, non-randomized clinical trial “Protarget” to establish short-term cultured neurospheres to preserve the heterogeneity of the tumour including cancer stem cells. We will then perform single cell RNA sequencing before and after drug screening. This setup will allow for a new approach to identify drug vulnerabilities at the single cell level. If successful in identifying drugs that leads to a clinical response, according to the "ProTarget" guidelines, we will consider scaling up the effort, to allow broader evaluation of efficacy. Our plan is to enroll 10 patients as a start. Patients will be selected based on ProTarget inclusion criteria and molecular profiling. We will further select patients with the following characteristics:1. IDH wildtype 2. High tumour purity (>50%). 3. High degree of intra-tumour heterogeneity.

Results

Enrollment for "Protarget" began in 2020 and our cohort will be part of this study, which is why enrollment has already started, but the first patient has not been enrolled yet. Clinical trial registry number for "Protarget" is NCT04341181.

Conclusion

This new and flexible approach to identify drug vulnerabilities at the single cell level in glioblastoma in order to find targeted therapies is a promising tool for future treatment of glioblastoma patients.

Absence of association between 2019-20 influenza vaccination and COVID-19: Results of the European I-MOVE-COVID-19 primary care project, March-August 2020

BACKGROUND

Claims of influenza vaccination increasing COVID-19 risk are circulating. Within the I-MOVE-COVID-19 primary care multicentre study, we measured the association between 2019-20 influenza vaccination and COVID-19.

METHODS

We conducted a multicentre test-negative case-control study at primary care level, in study sites in five European countries, from March to August 2020. Patients presenting with acute respiratory infection were swabbed, with demographic, 2019-20 influenza vaccination and clinical information documented. Using logistic regression, we measured the adjusted odds ratio (aOR), adjusting for study site and age, sex, calendar time, presence of chronic conditions. The main analysis included patients swabbed ≤7 days after onset from the three countries with <15% of missing influenza vaccination. In secondary analyses, we included five countries, using multiple imputation with chained equations to account for missing data.

RESULTS

We included 257 COVID-19 cases and 1631 controls in the main analysis (three countries). The overall aOR between influenza vaccination and COVID-19 was 0.93 (95% CI: 0.66-1.32). The aOR was 0.92 (95% CI: 0.58-1.46) and 0.92 (95% CI: 0.51-1.67) among those aged 20-59 and ≥60 years, respectively. In secondary analyses, we included 6457 cases and 69 272 controls. The imputed aOR was 0.87 (95% CI: 0.79-0.95) among all ages and any delay between swab and symptom onset.

CONCLUSIONS

There was no evidence that COVID-19 cases were more likely to be vaccinated against influenza than controls. Influenza vaccination should be encouraged among target groups for vaccination. I-MOVE-COVID-19 will continue documenting influenza vaccination status in 2020-21, in order to learn about effects of recent influenza vaccination.

Cognitive effects of interictal epileptiform discharges in children

Frequent interictal epileptiform discharges (IEDs) may have effects on cognition. We analysed a group of 182 children with different epilepsy syndromes as well as children with IEDs without observed seizures [corrected], with 24-h ambulatory EEG and cognitive tests. The IED index was estimated, in wakefulness and in sleep, as percentage of time in five categories (0%, <1%, 1-10%, ≥10-50% and ≥50%). IEDs were defined as spikes or spike-wave complexes, isolated or occurring serially (in runs) without evident clinical signs of a seizure. The IED categories were correlated to cognitive test results and epilepsy characteristics. The group of patients with diurnal IEDs in ≥10% of the EEG record showed impaired central information processing speed, short-term verbal memory and visual-motor integration. This effect was seen independently from other EEG-related and epilepsy-related characteristics, and independently from epilepsy syndrome diagnosis. The impact of the nocturnal IEDs was of less importance; only contributing partially to the slowing of central information processing speed. We conclude that frequent IEDs (in more than 10% of the record) in the awake EEG can impair cognitive performance in children. Whether children with a high diurnal spike frequency and low seizure frequency can benefit from antiepileptic treatment should be examined in controlled trials.

Nocturnal epileptiform EEG discharges, nocturnal epileptic seizures, and language impairments in children: review of the literature

This review addresses the effect on language function of nocturnal epileptiform EEG discharges and nocturnal epileptic seizures in children. In clinical practice, language impairment is frequently reported in association with nocturnal epileptiform activity. Vice versa, nocturnal epileptiform EEG abnormalities are a common finding in children with specific language impairment. We suggest a spectrum that is characterized by nocturnal epileptiform activity and language impairment ranging from specific language impairment to rolandic epilepsy, nocturnal frontal lobe epilepsy, electrical status epilepticus of sleep, and Landau-Kleffner syndrome. In this spectrum, children with specific language impairment have the best outcome, and children with electrical status epilepticus of sleep or Landau-Kleffner syndrome, the worst. The exact nature of this relationship and the factors causing this spectrum are unknown. We suggest that nocturnal epileptiform EEG discharges and nocturnal epileptic seizures during development will cause or contribute to diseased neuronal networks involving language. The diseased neuronal networks are less efficient compared with normal neuronal networks. This disorganization may cause language impairments.

Long-term neuropsychological performance in a cohort of children and adolescents after severe paediatric traumatic brain injury

OBJECTIVE

The purpose of the present study was to evaluate progress in neuropsychological performance in children and adolescents with severe paediatric traumatic brain injury (TBI), from admission to the rehabilitation centre up to 3-12 years after the trauma.

METHODS

Children and adolescents (n = 31, mean age at injury 11.8 years, SD = 3.8; at follow-up 18.8 years; SD = 4.5) who all had suffered a TBI participated. A comprehensive neuropsychological test battery was administered at the start of rehabilitation (T1), around discharge (T2) and in the long-term (at least 3 years after rehabilitation; T3). T1 and T2 were clinical assessments; T3 was executed as a follow-up measurement for this study.

RESULTS

At T1 and T2, most problems were in the domains of attention, memory and executive functioning. At the start of rehabilitation most deficits were with performal intelligence (61%); at discharge (mean length of stay 411 days) considerably less children had severe deficits on the intelligence domain (23%). At long-term follow-up, most problems were in the domains attention, mental speed and memory. From admission to discharge 42% of the children improved on two or more cognitive tests; from discharge to follow-up this percentage was 13%.

CONCLUSIONS

In this unique study a clinical cohort of children with severe TBI was followed for many years after injury. Most cognitive deficits were found in the early phase of rehabilitation. Most children did improve on cognitive functioning (40%) during the first year after their injury, whereas at follow-up most children had not changed. At follow-up, more than half of the children (54%) attended a regular school or had a regular job, corresponding to their age and pre-morbid functioning.

Sequence variability of the meningococcal lactoferrin-binding protein LbpB

The lactoferrin receptor of Neisseria meningitidis consists of two proteins, LbpA and LbpB. LbpB is considered a promising vaccine candidate, and therefore its sequence variability was studied. LbpB from five different strains exhibited 70-80% mutual identity at the amino acid level. Most sequence variability was found in two stretches with a high content of negatively charged amino acids. These stretches were sequenced from six additional strains. One of the stretches is of variable length and is missing in some of the strains. The other stretch is present in all strains, but varies considerably in its exact amino acid sequence. The high degree of variability is disadvantageous for vaccine development, but may be useful for epidemiological studies.