Australian multicentre study of current real-world prophylaxis practice in severe and moderate haemophilia A and B

INTRODUCTION

With the emergence of novel treatment products for haemophilia and an increasing focus on the benefits of pharmacokinetic driven individualized prophylaxis, robust national data with regard to current patterns of factor consumption and adherence are required.

AIM

To characterize current Australian practice with regard to use of prophylactic clotting factor infusions in patients with moderate or severe haemophilia A (HA) and haemophilia B (HB).

METHODS

This was a retrospective, non-interventional study utilizing Australian Bleeding Disorder Registry (ABDR) data collected over a 12 month period. Registered and consented patients with moderate or severe HA or HB without inhibitors were included.

RESULTS

A total of 718 HA (551 severe, 167 moderate) and 166 HB (87 severe, 79 moderate) patients were included. Regular prophylaxis was prescribed in 453 patients (82%) with severe HA, 42 patients (25%) with moderate HA, 66 patients (75%) with severe HB and 11 patients (14%) with moderate HB. Near universal prophylaxis was achieved in the paediatric subgroup. The mean weekly dose of factor VIII in severe HA was 84 international units/kg/wk (IU/kg/wk) vs 71 IU/kg/wk of factor IX in severe HB. Most patients on prophylaxis were treated ≥3 times/wk (HA) or 2 times/wk (HB). Non-adherence peaked in the 20-29 year age group. Older individuals on regular prophylaxis used more factor than was expected for their prescribed regimen.

CONCLUSION

Prophylaxis rates in severe haemophilia are comparable with other developed nations. The benefit of a national registry is demonstrable. Furthermore research into the underlying reasons for non-compliance in young adults with haemophilia is required.

Stress hormones promote EGFR inhibitor resistance in NSCLC: Implications for combinations with β-blockers

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) resistance mediated by T790M-independent mechanisms remains a major challenge in the treatment of non-small cell lung cancer (NSCLC). We identified a targetable mechanism of EGFR inhibitor resistance whereby stress hormones activate β2-adrenergic receptors (β2-ARs) on NSCLC cells, which cooperatively signal with mutant EGFR, resulting in the inactivation of the tumor suppressor, liver kinase B1 (LKB1), and subsequently induce interleukin-6 (IL-6) expression. We show that stress and β2-AR activation promote tumor growth and EGFR inhibitor resistance, which can be abrogated with β-blockers or IL-6 inhibition. IL-6 was associated with a worse outcome in EGFR TKI-treated NSCLC patients, and β-blocker use was associated with lower IL-6 concentrations and improved benefit from EGFR inhibitors. These findings provide evidence that chronic stress hormones promote EGFR TKI resistance via β2-AR signaling by an LKB1/CREB (cyclic adenosine 3',5'-monophosphate response element-binding protein)/IL-6-dependent mechanism and suggest that combinations of β-blockers with EGFR TKIs merit further investigation as a strategy to abrogate resistance.

Abstract 2774: Correlative analysis of systemic markers from a randomized trial assessing local consolidative therapy for non-small cell lung cancer (NSCLC) patients with oligometastatic disease

Introduction: We present serum correlative analysis from a phase II randomized trial to identify markers associated with progression free survival (PFS) in NSCLC.

Methods: NSCLC patients presenting with oligometastatic disease (≤3 metastases) were enrolled on a multi-institution phase II randomized trial (NCT01725165). Patients who did not progress after ≥3 months of first-line systemic therapy were randomized to upfront local consolidative therapy (LCT arm) to all sites of disease or at later progression (no-LCT arm). For correlative analyses, peripheral blood was collected from consenting patients after completion of initial systemic therapy but prior to randomization (baseline) and at each follow up. Serum cytokine and angiogenesis factors (CAFs) were analyzed via magnetic bead-based multiplex assay (Merck Millipore). Peripheral blood T cell receptor (TCR) repertoire was profiled by immunoSEQ (Adaptive Biotechnologies). Peripheral cell-free DNA (cfDNA) was subjected to next generation sequencing of a panel of cancer genes. Comparisons of PFS, the primary endpoint of this study, were conducted via log-rank test.

Results: After enrollment of 74 patients with a median follow up of 19 months, this study was closed early after the Data Safety Monitoring Committee review determined efficacy in the LCT arm. Of 49 randomized patients, correlative blood draws were conducted on 33 patients. Considering all patients, high baseline EGF (cutpoint 50 pg/ml; median PFS: 5.7 vs 19.8 mo), Eotaxin (cutpoint 110 pg/ml; median PFS: 5.7 vs 21 mo), TNF alpha (cutpoint 8 pg/ml; median PFS: 3.6 vs 17.9 mo), or low baseline GRO (cutpoint 600 pg/ml; median PFS: 17.9 vs 3.6 mo) were associated with longer PFS (all P<0.05). When considering individual treatment arms, LCT arm patients exhibiting low baseline MMP-2 (cutpoint 90 ug/ml; median PFS: 17.9 vs 5.3 mo) and no-LCT arm patients exhibiting low baseline GRO (cutpoint 600 pg/ml; median PFS: 21.0 vs 1.8 mo) or high baseline FGF-2 (cutpoint 58 pg/ml; median PFS: 2.2 vs 21.0 mo) exhibited longer PFS (all P<0.05). TCR repertoire and cfDNA profile analyses are underway.

Conclusions: In this exploratory analysis, we identified baseline CAFs associated with PFS. These finding are being validated in a larger cohort of patients. If validated, CAFs could be a biomarker to select patients with oligometastatic NSCLC for aggressive local treatment.

Citation Format: Chad Tang, John V. Heymach, Alexandre Reuben, Hai Tran, James Welsh, Jennifer Wargo, Zhongxing Liao, Anne Tsao, Eric Prado, Stephen Swisher, Jianjun Zhang, Daniel Gomez. Correlative analysis of systemic markers from a randomized trial assessing local consolidative therapy for non-small cell lung cancer (NSCLC) patients with oligometastatic disease [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2774. doi:10.1158/1538-7445.AM2017-2774

Metabolic and evolutionary patterns in the extremely acidophilic archaeon Ferroplasma acidiphilum YT

Ferroplasmaceae represent ubiquitous iron-oxidising extreme acidophiles with a number of unique physiological traits. In a genome-based study of Ferroplasma acidiphilum YT, the only species of the genus Ferroplasma with a validly published name, we assessed its central metabolism and genome stability during a long-term cultivation experiment. Consistently with physiology, the genome analysis points to F. acidiphilum YT having an obligate peptidolytic oligotrophic lifestyle alongside with anaplerotic carbon assimilation. This narrow trophic specialisation abridges the sugar uptake, although all genes for glycolysis and gluconeogenesis, including bifunctional unidirectional fructose 1,6-bisphosphate aldolase/phosphatase, have been identified. Pyruvate and 2-oxoglutarate dehydrogenases are substituted by 'ancient' CoA-dependent pyruvate and alpha-ketoglutarate ferredoxin oxidoreductases. In the lab culture, after ~550 generations, the strain exhibited the mutation rate of ≥1.3 × 10-8 single nucleotide substitutions per site per generation, which is among the highest values recorded for unicellular organisms. All but one base substitutions were G:C to A:T, their distribution between coding and non-coding regions and synonymous-to-non-synonymous mutation ratios suggest the neutral drift being a prevalent mode in genome evolution in the lab culture. Mutations in nature seem to occur with lower frequencies, as suggested by a remarkable genomic conservation in F. acidiphilum YT variants from geographically distant populations.

Mapping in-vivo optic nerve head strains caused by intraocular and intracranial pressures

Although it is well documented that abnormal levels of either intraocular (IOP) or intracranial pressure (ICP) can lead to potentially blinding conditions, such as glaucoma and papilledema, little is known about how the pressures actually affect the eye. Even less is known about potential interplay between their effects, namely how the level of one pressure might alter the effects of the other. Our goal was to measure in-vivo the pressure-induced stretch and compression of the lamina cribrosa due to acute changes of IOP and ICP. The lamina cribrosa is a structure within the optic nerve head, in the back of the eye. It is important because it is in the lamina cribrosa that the pressure-induced deformations are believed to initiate damage to neural tissues leading to blindness. An eye of a rhesus macaque monkey was imaged in-vivo with optical coherence tomography while IOP and ICP were controlled through cannulas in the anterior chamber and lateral ventricle, respectively. The image volumes were analyzed with a newly developed digital image correlation technique. The effects of both pressures were highly localized, nonlinear and non-monotonic, with strong interactions. Pressure variations from the baseline normal levels caused substantial stretch and compression of the neural tissues in the posterior pole, sometimes exceeding 20%. Chronic exposure to such high levels of biomechanical insult would likely lead to neural tissue damage and loss of vision. Our results demonstrate the power of digital image correlation technique based on non-invasive imaging technologies to help understand how pressures induce biomechanical insults and lead to vision problems.

Biology of archaea from a novel family Cuniculiplasmataceae (Thermoplasmata) ubiquitous in hyperacidic environments

The order Thermoplasmatales (Euryarchaeota) is represented by the most acidophilic organisms known so far that are poorly amenable to cultivation. Earlier culture-independent studies in Iron Mountain (California) pointed at an abundant archaeal group, dubbed ‘G-plasma’. We examined the genomes and physiology of two cultured representatives of a Family Cuniculiplasmataceae, recently isolated from acidic (pH 1–1.5) sites in Spain and UK that are 16S rRNA gene sequence-identical with ‘G-plasma’. Organisms had largest genomes among Thermoplasmatales (1.87–1.94 Mbp), that shared 98.7–98.8% average nucleotide identities between themselves and ‘G-plasma’ and exhibited a high genome conservation even within their genomic islands, despite their remote geographical localisations. Facultatively anaerobic heterotrophs, they possess an ancestral form of A-type terminal oxygen reductase from a distinct parental clade. The lack of complete pathways for biosynthesis of histidine, valine, leucine, isoleucine, lysine and proline pre-determines the reliance on external sources of amino acids and hence the lifestyle of these organisms as scavengers of proteinaceous compounds from surrounding microbial community members. In contrast to earlier metagenomics-based assumptions, isolates were S-layer-deficient, non-motile, non-methylotrophic and devoid of iron-oxidation despite the abundance of methylotrophy substrates and ferrous iron in situ, which underlines the essentiality of experimental validation of bioinformatic predictions.

RADIATION DOSE MEASUREMENTS FOR HIGH-INTENSITY LASER INTERACTIONS WITH SOLID TARGETS AT SLAC

A systematic study of photon and neutron radiation doses generated in high-intensity laser-solid interactions is underway at SLAC National Accelerator Laboratory. These laser-solid experiments are being performed using a 25 TW (up to 1 J in 40 fs) femtosecond pulsed Ti:sapphire laser at the Linac Coherent Light Source's (LCLS) Matter in Extreme Conditions (MEC) facility. Radiation measurements were performed with passive and active detectors deployed at various locations inside and outside the target chamber. Results from radiation dose measurements for laser-solid experiments at SLAC MEC in 2014 with peak intensity between 10¹⁸ and 7.1 × 10¹⁹ W cm^-2 are presented.