AB0198 EFFICACY AND SAFETY AFTER TRANSITION FROM REFERENCE ADALIMUMAB TO CT-P17 (ADALIMUMAB BIOSIMILAR: 100 MG/ML) IN COMPARISON WITH THE MAINTAINED TREATMENT (CT-P17 OR REFERENCE ADALIMUMAB) IN PATIENTS WITH MODERATE-TO-SEVERE ACTIVE RHEUMATOID ARTHRITIS: 1-YEAR RESULT

Background:

Therapeutic equivalence of CT-P17 to reference adalimumab (ref-adalimumab) has been shown in patients with moderate-to-severe active rheumatoid arthritis (RA) through primary 24-week results [1]. Here, efficacy, pharmacokinetics (PK), safety and immunogenicity results up to 52-week, including transition data from ref-adalimumab to CT-P17 are presented.

Objectives:

To evaluate efficacy, PK, safety and immunogenicity when switched from ref-adalimumab to CT-P17 compared to maintaining CT-P17 or ref-adalimumab.

Methods:

In this study, 648 moderate-to-severe active RA patients despite methotrexate treatment were randomized (1:1) to either CT-P17 or ref-adalimumab and treated with doses of 40 mg every 2 weeks up to Week 24. Prior to dosing at Week 26, 608 patients were randomized again to either maintaining their treatments or being switched from ref-adalimumab to CT-P17. Efficacy, PK, safety, and immunogenicity were assessed up to Week 52.

Results:

After the second randomization, 303 patients continued with CT-P17, 153 patients continued with ref-adalimumab and 151 patients switched from ref-adalimumab to CT-P17 treatments, up to Week 48. Demographics and baseline characteristics were similar among the 3 groups. Sustained and comparable efficacy in terms of ACR20/50/70 response rates was achieved not only in the maintenance groups (CT-P17 or ref-adalimumab) but also in the switched from ref-adalimumab to CT-P17 group up to Week 52 (Figure 1).

Figure 1.

ACR 20/50/70 Response Rates up to 1 YearAbbreviation: ref-adalimumab, reference adalimumab.Note. There were patients who could not visit the study site due to COVID-19 pandemic and were counted as nonresponder for ACR response at Week 52.

In terms of PK, mean trough serum concentration (Ctrough) were maintained after Week 24 in all 3 groups. The observed mean Ctrough were within the reported therapeutic ranges of ref-adalimumab trough levels in RA patients (5-8 μg/mL).

The safety profile after transition was comparable among the 3 groups (Table 1). The most common treatment-emergent adverse events (TEAEs) was neutropenia. Similar proportions of patients in all 3 groups experienced at least 1 TEAE: injection site reactions, hypersensitivity/allergic reactions and infections. One malignancy (basal cell carcinoma; unrelated) was reported in the ref-adalimumab maintenance group. Safety data accumulated over 1 year also showed comparable results among the 3 groups. Anti-drug antibody (ADA) and neutralizing antibody (NAb) results were similar among the 3 groups. At Week 52, the proportions of patients who had ADA/NAbs were 28.4%/24.8% patients in CT-P17 maintenance, 27.0%/24.3% patients in ref-adalimumab maintenance and 28.3%/26.3% patients in switched to CT-P17 groups.

Conclusion:

Single transition from ref-adalimumab to CT-P17 was efficacious and safe without increase in immunogenicity. Also, efficacy, PK, safety and immunogenicity profiles were comparable between CT-P17 and ref-adalimumab up to Week 52.

References:

[1]J Kay et al, 2020. Poster Presented at ACR Convergence 2020.

Table 1.

Overview of TEAEs from Weeks 26 to 52 (Safety Population – second random subset)

Patients, n (%)Second RandomizationCT-P17 Maintenance(N=303)Ref-ada Maintenance(N=152)Switched to CT-P17 (N=152)≥1 TEAE121 (39.9)69 (45.4)73 (48.0)≥1 TESAE6 (2.0)3 (2.0)5 (3.3)≥1 TEAE leading to study drug discontinuation3 (1.0)2 (1.3)5 (3.3)≥1 TEAE classified as hypersensitivity/allergic reactions2 (0.7)1 (0.7)0 (0)≥1 TEAE classified as injection site reactions1 (0.3)4 (2.6)1 (0.7)≥1 TEAE classified as infection54 (17.8)41 (27.0)28 (18.4)≥1 TEAE classified as malignancy0 (0)1 (0.7)0 (0)

Abbreviations: Ref-ada, reference adalimumab; TEAE, treatment-emergent adverse event; TESAE, treatment-emergent serious adverse event.

Disclosure of Interests:

Daniel Furst Speakers bureau: CME, Consultant of: Amgen, Corbus, Galapagos, Horizon, Kadmon, Pfizer, Talaris, Grant/research support from: Corbus, CSL Behring, Galapagos, Gilead, GSK, Horizon, Kadmon, Novartis, Pfizer, Roche/Genetech, Talaris, Edward Keystone Speakers bureau: Amgen, AbbVie, F. Hoffmann-La Roche Inc., Janssen Inc., Merck, Novartis, Pfizer Pharmaceuticals, Sanofi Genzyme, Consultant of: AbbVie, Amgen, Bristol-Myers Squibb Company, Celltrion Inc., Myriad Autoimmune, F. Hoffmann-La Roche Inc, Gilead, Janssen Inc., Lilly Pharmaceuticals, Merck, Pfizer Pharmaceuticals, Sandoz, Sanofi-Genzyme, Samsung Bioepis, Grant/research support from: Amgen, Merck, Pfizer Pharmaceuticals, PuraPharm, Jonathan Kay Consultant of: AbbVie, Inc., Boehringer Ingelheim GmbH, Celltrion Healthcare Co. Ltd., Jubilant Radiopharma, Merck & Co., Inc., Pfizer Inc., Samsung Bioepis, Sandoz Inc., Scipher Medicine, UCB, Inc., Grant/research support from: Paid to the University of Massachusetts Medical School: Gilead Sciences Inc., Novartis Pharmaceuticals Corp., Pfizer Inc., Janusz Jaworski: None declared, Rafal Wojciechowski: None declared, Piotr Wiland Speakers bureau: Eli Lilly, Sanofi Aventis, Novartis, Sandoz, Consultant of: Eli Lilly, Novartis, Sandoz, Anna Dudek: None declared, Marek Krogulec: None declared, Sławomir Jeka Speakers bureau: Novartis, Pfizer, Roche, Lilly, Teva, MSD, Abbvie, Sandoz, Egis, Medac, Consultant of: Novartis, Pfizer, Roche, Lilly, Teva, MSD, Abbvie, Sandoz, Egis, Medac, Agnieszka Zielinska: None declared, Jakub Trefler: None declared, Katarzyna Bartnicka-Masłowska: None declared, Magdalena Krajewska-Wlodarczyk Speakers bureau: Abbvie, Eli Lilly, Novartis, Roche, Piotr Klimiuk: None declared, Sang Joon Lee Employee of: Celltrion, Inc., Sung Hyun Kim Employee of: Celltrion, Inc., YunJu Bae Employee of: Celltrion, Inc., GoEun Yang Employee of: Celltrion, Inc., JaeKyoung Yoo Employee of: Celltrion, Inc., TaeKyung Kim Employee of: Celltrion, Inc.

Clinical and electrophysiological characteristics of extra-pulmonary vein triggers in patients who underwent catheter ablation for atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

Extra-pulmonary vein (PV) triggers play significant roles in atrial fibrillation (AF) recurrence after AF catheter ablation (AFCA).

Purpose

We explore the clinical and electrophysiological characteristics of extra-PV triggers in de novo and repeat-AFCA procedure.

Methods

We included 2,151 patients who had de novo AFCA and 319 repeat AFCA (female 28.0%, 59.1 ± 10.8 years old, paroxysmal AF 65.1%) those underwent post-procedural isoproterenol (ISO) provocation tests. We analysed the clinical, electrophysiological, and procedure-related factors associated with extra-PV triggers.

Results

Extra-PV triggers were documented in 11.9% (1.19 ± 0.42 foci) after de novo-AFCA and 27.0% (1.37 ± 0.65 foci) after repeat-AFCA (p = 0.004). LA volume index (OR 1.02 [1.01-1.03], p = 0.004), history of vascular disease (OR 0.55[0.31-0.91], p = 0.028) and Lead I amplitude of electrocardiogram (OR <0.01 [<0.01-0.62], p = 0.032) were independently associated with the existence of extra-PV triggers in de-novo procedure. Women (OR 1.84 [1.03-3.25], p = 0.037) and LA appendage volume (OR 1.04 [1.01-1.07] p = 0.027) were independently associated with extra-PV triggers during the redo-mapping procedure. Septum (28.4%), coronary sinus (24.0%), and superior vena cava (19.6%) were common extra-PV foci, and septal foci were more commonly found in repeat mapping (38.4% vs. 25.0%, p = 0.025). Among 65 patients who showed extra-PV at the repeat procedures, 19 (29.2%) matched with previous focal or empirical extra-PV ablation sites and 9 (13.8%) were multiple or unmappable sites. AF recurrence rates were significantly higher in both patients with extra-PV triggers after de novo procedures (Log-rank P <0.001; HR 1.93 [1.58-2.36], p= <0.001) and repeat procedures (Log-rank P <0.001, HR 1.87 [1.29-2.70], p= <0.001).

Conclusion

ISO provoked extra-PV triggers commonly found in AF patients with significant remodelling and previous empirical or focal extra-PV ablations. Existence of extra-PV triggers were independently associated with poorer rhythm outcome after both de novo and repeat AFCA. Denovo AF ablation outcome OverallExtra-PV triggers (-)Extra-PV triggers (+)p-value(n = 2151)(n = 1895)(n = 256)Age, yrs58.98 ± 10.9558.73 ± 11.0360.76 ± 10.200.006Male, (%)1550 ( 72.1)1389 ( 73.3)161 ( 62.9)0.001Follow up duration, month50.30 (37.71)51.65 (37.95)40.71 (34.58)<0.001Early recurrence (%)579 ( 27.8)455 ( 24.9)124 ( 48.4)<0.001Clinical recurrence (%)699 ( 33.6)584 ( 32.0)115 ( 44.9)<0.001Abstract Figure. AF free survival according to Extra PVT

Computational modeling for antiarrhythmic drugs for atrial fibrillation according to the genotypes

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was supported by a grant [HI19C0114] from the Ministry of Health and Welfare. Additionally, the work was funded by grants [NRF-2019R1C1C100907512], and [NRF-2020R1A2B01001695] from the Basic Science Research Program run by the National Research Foundation of Korea (NRF) under the Ministry of Science, ICT & Future Planning (MSIP).

Background

The efficacy of antiarrhythmic drugs (AAD) can vary in patients with atrial fibrillation (AF) and the PITX2 gene affects the responsiveness of AADs. We explored the virtual AAD (V-AAD) responses between wild-type and PITX2+/- deficient AF conditions by realistic in-silico AF modeling.

Methods

We tested the V-AADs in AF modeling integrated with patients’ 3D-computed tomography and 3D-electroanatomical mapping, acquired in 25 patients (68% male, 59.8 ± 9.8 years old, 32.0% paroxysmal type). The ion currents for the PITX2+/- deficiency and each AAD (amiodarone, sotalol, dronedarone, flecainide, and propafenone) were defined based on previous publications.

Results

We compared the wild-type and PITX2+/- deficiency in terms of the action potential duration (APD90), conduction velocity (CV), maximal slope of restitution (Smax), and wave-dynamic parameters, such as the dominant frequency (DF), phase singularities (PS), and AF termination rates according to the V-AADs. The PITX2+/- deficient model exhibited a shorter APD90 (p < 0.001), a lower Smax (p < 0.001), mean DF (p = 0.012), PS number (p < 0.001), and a longer AF cycle length (AFCL, p = 0.011). Five V-AADs changed the electrophysiology in a dose dependent manner. AAD-induced AFCL lengthening (p < 0.001) and reductions in the CV (p = 0.033), peak DF (p < 0.001) and PS number (p < 0.001) were more significant in PITX2+/- deficient than wild-type AF. PITX2+/- deficient AF was easier to terminate with class IC AADs than the wild-type AF (p = 0.018).

Conclusions

The computational modeling-guided AAD test was feasible for evaluating the efficacy of multiple AADs in patients with AF. AF wave-dynamics and electrophysiological characteristics are different among the PITX2 deficient and the wild-type genotype models. BaselineChanges after AADClass ICClass IIIWild-typePITX2+/-p-valueWild-typePITX2+/-p-valueWild-typePITX2+/-p-valueWild-typePITX2+/-p-valueAPD90, (ms)243.7 ± 33.8184.4 ± 15.5<0.00138.2 ± 37.343.4 ± 56.20.223275.9 ± 43.5219.0 ± 39.2<0.001284.9 ± 32.8233.8 ± 71.4<0.001CV, (m/s)0.78 ± 0.320.70 ± 0.210.347-0.15 ± 0.18-0.20 ± 0.260.0330.63 ± 0.320.53 ± 0.300.0270.60 ± 0.360.43 ± 0.33<0.001Mean Smax0.787 ± 0.280.531 ± 0.18<0.0010.005 ± 0.260.115 ± 0.24<0.0010.828 ± 0.310.694 ± 0.320.0030.768 ± 0.320.608 ± 0.27<0.001Mean AFCL, (ms)146.96 ± 24.61164.78 ± 22.730.01122.62 ± 24.5537.92 ± 32.72<0.001165.44 ± 36.96190.85 ± 35.61<0.001169.05 ± 25.26203.35 ± 34.78<0.001Peak DF, (Hz)10.68 ± 2.9711.82 ± 3.340.211-2.98 ± 4.94-5.46 ± 4.66<0.00110.01 ± 4.397.23 ± 4.20<0.0016.30 ± 4.325.80 ± 4.070.301Mean DF, (Hz)6.80 ± 0.886.22 ± 0.710.012-1.95 ± 2.44-2.20 ± 1.990.2065.75 ± 1.784.53 ± 2.00<0.0014.14 ± 2.393.69 ± 2.000.077PS Number, (N)101086 ± 9608814150 ± 24778<0.001-59322 ± 99288-7409 ± 27856<0.00150579 ± 6523611568 ± 21868<0.00132951 ± 558643524 ± 8302<0.001PS Life Span, (ms)109.36 ± 113.90102.24 ± 226.640.889-24.87 ± 72.06-41.38 ± 126.350.073103.36 ± 180.6868.05 ± 162.790.14871.91 ± 141.8655.99 ± 217.970.454Table. Effects of AADs in the Wild-type and PITX2+/- Deficiency groupAbstract Figure. Wild-type vs. PITX2+/- baseline model

Long-term outcomes of empirical extra-pulmonary vein linear ablation in patients with persistent atrial fibrillation

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was supported by grants [HI18C0070] and [HI19C0114] from the Korea Health 21 R&D Project, Ministry of Health and Welfare, and a grant [NRF-2020R1A2B01001695] from the Basic Science Research Program run by the National Research Foundation of Korea (NRF).

Background

Although extra-pulmonary vein (PV) left atrial (LA) linear ablation has been performed during catheter ablation (CA) of persistent atrial fibrillation (PeAF), the long-term efficacy and safety of this procedure have not yet been verified.

Purpose

We investigated whether an anterior line (AL) and posterior box ablation (POBA) in addition to circumferential PV isolation (CPVI) improves the rhythm without worsening the LA function in PeAF patients.

Methods

We retrospectively compared the additional AL + POBA and CPVI alone groups in 604 patients with PeAF who underwent regular rhythm follow-ups (16.9%; males 79.3%, 58.5 ± 10.7 years of age) after propensity score matching. The primary endpoint was AF recurrence after single procedures and secondary endpoints were the cardioversion rate, response to anti arrhythmic drugs, LA changes, and re-conduction rates of the de-novo ablation lesion set.

Results

After a mean follow-up of 45.2 ± 33.6 months, the clinical recurrence rate did not significantly differ between the two groups (log-rank p = 0.554) despite longer procedure times in the AL + POBA group (p < 0.001). Atrial tachycardia recurrences (p = 0.001) and the cardioversion rates after ablation (p < 0.001) were higher in the AL + POBA group than CPVI group. AL + POBA was associated with better rhythm outcomes in patients with large anterior LA volume indices (p for interaction 0.037) and low mean LAA(left atrial appendage) voltages (p for interaction 0.019). In repeat procedures, the LA pulse pressure elevation was significant after the AL + POBA.

Conclusion

In patients with PeAF, an AL + POBA in addition to the CPVI did not improve the rhythm outcomes nor influence the long-term safety, and lead to more extended procedures. Procedure outcomes OverallAL + POBACPVIp-value(n = 604)(n = 302)(n = 302)Procedure time, min190.8 ± 62.6226.9 ± 49.4154.6 ± 52.8<0.001Ablation time, sec5079 ± 19566420 ± 13723738± 1475<0.001Overall complications24 (4.0)13 (4.3)11 (3.6)0.835Early recurrence, n (%)277 (45.9)129 (42.7)148 (49.0)0.142Recurrence type AT, n (% in early recur)77 (27.8)51 (39.5)26 (17.6)<0.001Clinical recurrence within 1-year, n(%)116 (19.2)52 (17.2)65 (21.5)0.256Recurrence type AT, n (% in clinical recur)60 (23.1)46 (30.7)14 (12.7)0.001Cardioversion, n (% in total recur/ % overall)105 (40.4/17.4)74 (49.3/24.5)31 (28.1/10.3)<0.001POBA, posterior box ablation; AL, anterior line; CPVI, circumferential pulmonary vein isolation; AT, atrial tachycardia;Abstract Figure. Long term ablation outcome

Elliptic Flow of Electrons from Beauty-Hadron Decays in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

The elliptic flow of electrons from beauty hadron decays at midrapidity (|y|<0.8) is measured in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV with the ALICE detector at the LHC. The azimuthal distribution of the particles produced in the collisions can be parametrized with a Fourier expansion, in which the second harmonic coefficient represents the elliptic flow, v_{2}. The v_{2} coefficient of electrons from beauty hadron decays is measured for the first time in the transverse momentum (p_{T}) range 1.3-6  GeV/c in the centrality class 30%-50%. The measurement of electrons from beauty-hadron decays exploits their larger mean proper decay length cτ≈500  μm compared to that of charm hadrons and most of the other background sources. The v_{2} of electrons from beauty hadron decays at midrapidity is found to be positive with a significance of 3.75  σ. The results provide insights into the degree of thermalization of beauty quarks in the medium. A model assuming full thermalization of beauty quarks is strongly disfavored by the measurement at high p_{T}, but is in agreement with the results at low p_{T}. Transport models including substantial interactions of beauty quarks with an expanding strongly interacting medium describe the measurement within uncertainties.

Dendritic and parallel processing of visual threats in the retina control defensive responses

Approaching predators cast expanding shadows (i.e., looming) that elicit innate defensive responses in most animals. Where looming is first detected and how critical parameters of predatory approaches are extracted are unclear. In mice, we identify a retinal interneuron (the VG3 amacrine cell) that responds robustly to looming, but not to related forms of motion. Looming-sensitive calcium transients are restricted to a specific layer of the VG3 dendrite arbor, which provides glutamatergic input to two ganglion cells (W3 and OFFα). These projection neurons combine shared excitation with dissimilar inhibition to signal approach onset and speed, respectively. Removal of VG3 amacrine cells reduces the excitation of W3 and OFFα ganglion cells and diminishes defensive responses of mice to looming without affecting other visual behaviors. Thus, the dendrites of a retinal interneuron detect visual threats, divergent circuits downstream extract critical threat parameters, and these retinal computations initiate an innate survival behavior.

Circulating immune cell profiles detected by mass cytometry differ significantly between patients with predominantly calcified and predominantly non-calcified coronary atherosclerosis

Background/Introduction

Inflammation is now a well-established component of the pathophysiology of coronary artery disease (CAD), but it is unknown whether atherosclerosis is associated with a distinct circulating immune cell profile. Mass cytometry time-of-flight (CYTOF) is a new precision technology which can be used to assess leukocyte populations comprehensively.

Purpose

To determine if patients with calcified and non-calcified (soft) coronary plaque have distinct circulating immune cell profiles when compared to healthy controls, and to assess whether this could be used to detect sub-clinical CAD.

Methods

Patients referred for a CT coronary angiogram were recruited; blood samples were collected and peripheral blood mononuclear cells (PBMCs) were isolated. Imaging data was analysed using a modified Gensini scoring system which incorporated plaque composition, with higher weighting given to soft plaque. The modified Gensini scores were then used to further segregate into calcified-predominant and soft-predominant disease groups. CYTOF analysis was performed on the PBMCs, with groups as outlined in Table 1.

Results

Age was significantly higher in the CAD+ group, but all other demographic features and risk factors did not differ between groups. Patients with predominantly calcified disease showed an increase in memory CD8 T cells (p=0.004), an increase in CD 39+ CD4 T cells (p=0.028), and a decrease in naïve CD8 T cells (p=0.005), which suggests an accumulated memory response in more quiescent disease. Patients with predominantly soft-plaque disease have higher pro-inflammatory monocyte populations (p=0.013) and proliferative CD4 T cell populations (p=0.011), suggesting acute innate and adaptive responses to biologically active plaque.

Conclusions

This pilot study has shown that further study should be pursued into the utility of CYTOF to identify sub-clinical CAD through differences in peripheral circulating immune cell profiles.

Figure 1

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): National Health and Medical Research Council of Australia, Heart Research Australia

Measurement of the Low-Energy Antideuteron Inelastic Cross Section

In this Letter, we report the first measurement of the inelastic cross section for antideuteron-nucleus interactions at low particle momenta, covering a range of 0.3≤p<4  GeV/c. The measurement is carried out using p-Pb collisions at a center-of-mass energy per nucleon-nucleon pair of sqrt[s_{NN}]=5.02  TeV, recorded with the ALICE detector at the CERN LHC and utilizing the detector material as an absorber for antideuterons and antiprotons. The extracted raw primary antiparticle-to-particle ratios are compared to the results from detailed ALICE simulations based on the geant4 toolkit for the propagation of (anti)particles through the detector material. The analysis of the raw primary (anti)proton spectra serves as a benchmark for this study, since their hadronic interaction cross sections are well constrained experimentally. The first measurement of the inelastic cross section for antideuteron-nucleus interactions averaged over the ALICE detector material with atomic mass numbers ⟨A⟩=17.4 and 31.8 is obtained. The measured inelastic cross section points to a possible excess with respect to the Glauber model parametrization used in geant4 in the lowest momentum interval of 0.3≤p<0.47  GeV/c up to a factor 2.1. This result is relevant for the understanding of antimatter propagation and the contributions to antinuclei production from cosmic ray interactions within the interstellar medium. In addition, the momentum range covered by this measurement is of particular importance to evaluate signal predictions for indirect dark-matter searches.

β-actin contributes to open chromatin for activation of the adipogenic pioneer factor CEBPA during transcriptional reprograming

Adipogenesis is regulated by a cascade of signals that drive transcriptional reprogramming in adipocytes. Here, we report that nuclear actin regulates the chromatin states that establish tissue- specific expression during adipogenesis. To study the role of β-actin in adipocyte differentiation, we conducted RNA sequencing on wild-type and β-actin knockout mouse embryonic fibroblasts (MEFs) after reprograming to adipocytes. We found that β-actin depletion affects induction of several adipogenic genes during transcriptional reprograming. This impaired regulation of adipogenic genes is linked to reduced expression of the pioneer factor Cebpa and is rescued by reintroducing NLS-tagged β-actin. ATAC-Seq in knockout MEFs revealed that actin-dependent reduction of Cebpa expression correlates with decreased chromatin accessibility and loss of chromatin association of the ATPase Brg1. This, in turn, impairs CEBPB's association with its Cebpa promoter-proximal binding site during adipogenesis. We propose a role for the nuclear β-actin pool in maintaining open chromatin for transcriptional reprogramming during adipogenic differentiation.

Probing the Effects of Strong Electromagnetic Fields with Charge-Dependent Directed Flow in Pb-Pb Collisions at the LHC

The first measurement at the LHC of charge-dependent directed flow (v_{1}) relative to the spectator plane is presented for Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV. Results are reported for charged hadrons and D^{0} mesons for the transverse momentum intervals p_{T}>0.2  GeV/c and 3<p_{T}<6  GeV/c in the 5%-40% and 10%-40% centrality classes, respectively. The difference between the positively and negatively charged hadron v_{1} has a positive slope as a function of pseudorapidity η, dΔv_{1}/dη=[1.68±0.49(stat)±0.41(syst)]×10^{-4}. The same measurement for D^{0} and D[over ¯]^{0} mesons yields a positive value dΔv_{1}/dη=[4.9±1.7(stat)±0.6(syst)]×10^{-1}, which is about 3 orders of magnitude larger than the one of the charged hadrons. These measurements can provide new insights into the effects of the strong electromagnetic field and the initial tilt of matter created in noncentral heavy ion collisions on the dynamics of light (u, d, and s) and heavy (c) quarks. The large difference between the observed Δv_{1} of charged hadrons and D^{0} mesons may reflect different sensitivity of the charm and light quarks to the early time dynamics of a heavy ion collision. These observations challenge some recent theoretical calculations, which predicted a negative and an order of magnitude smaller value of dΔv_{1}/dη for both light flavor and charmed hadrons.

Evidence of Spin-Orbital Angular Momentum Interactions in Relativistic Heavy-Ion Collisions

The first evidence of spin alignment of vector mesons (K^{*0} and ϕ) in heavy-ion collisions at the Large Hadron Collider (LHC) is reported. The spin density matrix element ρ_{00} is measured at midrapidity (|y|<0.5) in Pb-Pb collisions at a center-of-mass energy (sqrt[s_{NN}]) of 2.76 TeV with the ALICE detector. ρ_{00} values are found to be less than 1/3 (1/3 implies no spin alignment) at low transverse momentum (p_{T}<2  GeV/c) for K^{*0} and ϕ at a level of 3σ and 2σ, respectively. No significant spin alignment is observed for the K_{S}^{0} meson (spin=0) in Pb-Pb collisions and for the vector mesons in pp collisions. The measured spin alignment is unexpectedly large but qualitatively consistent with the expectation from models which attribute it to a polarization of quarks in the presence of angular momentum in heavy-ion collisions and a subsequent hadronization by the process of recombination.