THU0063 DIFFERENTIAL PHARMACODYNAMIC EFFECTS OF ABATACEPT AND ADALIMUMAB ON THE SERUM PROTEOME OF PATIENTS WITH RA USING THE SOMASCAN® PLATFORM

Background:

Abatacept (ABA) versus adaliMumab (ADA) comParison in bioLogic-naïvERA subjects with background MTX (AMPLE) was a Phase IIIb clinical trial to compare the safety, efficacy and radiographic outcomes of ABA vs ADA in patients with RA who exhibited an inadequate response to MTX and who were naïve to biologic DMARDs.1While both therapies demonstrated similar efficacy across multiple outcomes, their mechanisms of action (MoAs) are quite different; ABA is a T-cell co-stimulation modulator and ADA is a TNFα inhibitor. Previous transcriptomic analysis of the whole blood samples showed differential pharmacodynamic (PD) effects between the treatments.1–3

Objectives:

To expand our understanding of differential PD changes in the serum proteome over time in patients treated with ABA or ADA in AMPLE using a novel proteomic platform.

Methods:

Serum was available from 440 patients in AMPLE at four time points (Days 1, 85, 365 and 729). Serum samples from the patients in AMPLE and 123 healthy individuals with matching demographics were subjected to proteomic quantification by a highly multiplexed DNA aptamer technology with wide dynamic ranges (SomaLogic SomaScan®platform).4A linear model analysis was used to identify protein abundance changes over time and changes specific to treatment. Other covariates included in the model were country of origin, ethnicity and sex. Additionally, patient effect was adjusted for as a random factor.

Results:

Both treatments exhibited a significant PD effect on serum proteome over the course of the 2-year trial, with 73 proteins modulated by ABA and 125 by ADA. There were large overlaps between the two treatments, including proteins associated with RA, such as C-X-C motif chemokine ligand 13 (CXCL13), matrix metalloproteinase-3 (MMP3) and serum amyloid A1/A2 (SAA1/2). Changes in the levels of these proteins may be indicative of general improvement of the disease. The proteins modulated by the treatments were enriched in the G-protein coupled receptor (GPCR) signalling and innate immunity pathways. Among the proteins that exhibited significantly different PD effects between the treatments were CRP, CC chemokine ligand 17 (CCL17) and β-defensin 112 (Figure). While patients showed marked improvement in their symptoms after 2 years of treatment, the overall serum proteomic profiles of the patients were still different from those of a normal healthy population.

Conclusion:

The SomaScan®platform provides a robust method for quantifying the PD change in a broad portion of the serum proteome in clinical trials. In AMPLE, abatacept was more selective than adalimumab in modulating protein biomarkers in patients with RA, though there was large overlap in proteins modulated by both treatments. The treatment-specific changes may reflect the different MoAs leading to similar clinical outcomes. While patients in both groups benefited from treatments, their serum proteome remained notably different from that of a healthy population. Further analysis by responder status may provide additional links between the treatment responses and proteomic changes. Proteomic approaches as described in our study could contribute to clinical trials and help shape treatment strategies for patients with RA.

References:

[1]Schiff M, et al.Ann Rheum Dis2014;73:86–94.

[2]Bandyopadhyay S, et al.Arthritis Rheum2014;66:Abstract 1520.

[3]Sokolove J, et al.Ann Rheum Dis2016;75:709–14.

[4]Gold L, et al.PLoS One2010;5:e15004.

Disclosure of Interests:

David Galbraith Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Minal Caliskan Employee of: Bristol-Myers Squibb, Omar Jabado Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Sarah Hu Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Roy Fleischmann Grant/research support from: AbbVie, Akros, Amgen, AstraZeneca, Bristol-Myers Squibb, Boehringer, IngelhCentrexion, Eli Lilly, EMD Serono, Genentech, Gilead, Janssen, Merck, Nektar, Novartis, Pfizer, Regeneron Pharmaceuticals, Inc., Roche, Samsung, Sandoz, Sanofi Genzyme, Selecta, Taiho, UCB, Consultant of: AbbVie, ACEA, Amgen, Bristol-Myers Squibb, Eli Lilly, Gilead, GlaxoSmithKline, Novartis, Pfizer, Sanofi Genzyme, UCB, Michael Weinblatt Grant/research support from: Amgen, Bristol-Myers Squibb, Crescendo, Lily, Sanofi/Regeneron, Consultant of: AbbVie, Amgen, Bristol-Myers Squibb, Crescendo, Gilead, Horizon, Lily, Pfizer, Roche, Sean Connolly Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Michael A Maldonado Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Sheng Gao Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb

SAT0104 MAINTENANCE OF SDAI REMISSION AND PATIENT-REPORTED OUTCOMES (PROS) FOLLOWING DOSE DE-ESCALATION OF ABATACEPT IN MTX-NAÏVE, ANTI-CITRULLINATED PROTEIN ANTIBODY (ACPA)+ PATIENTS WITH EARLY RA: RESULTS FROM AVERT-2, A RANDOMISED PHASE IIIB STUDY

Background:

The Phase IIIbAssessingVeryEarlyRATreatment (AVERT)-2 trial (NCT02504268) evaluated SC abatacept (ABA) + MTX vs ABA placebo (PBO) + MTX in ACPA+ patients (pts) with early, active RA.1Results from the 56-wk induction period (IP) showed a significantly greater proportion of pts treated with ABA + MTX (vs MTX alone) reported clinically meaningful improvements in HAQ-DI, global disease activity and pain, which were sustained at 52 wks.2

Objectives:

To report maintenance of SDAI remission and PROs from the AVERT-2 de-escalation (D-E) period.

Methods:

Pts received blinded SC ABA (125 mg once wkly [QW]) + MTX or ABA PBO + MTX induction treatment for 56 wks. In this analysis, pts who completed induction with ABA + MTX and had sustained SDAI remission (≤3.3 at Wks 40 and 52) were re-randomised 1:1:1 to ABA QW + MTX, stepwise D-E (ABA every other wk + MTX for 24 wks then ABA PBO + MTX for 24 wks), or ABA QW + MTX PBO for 48 wks in the D-E period. PROs included physical function (HAQ-DI [0–3; decrease=improvement] and Short-Form 36 [SF-36] v2.0 Physical Functioning Scale [PFS]; 0–100; increase=improvement), and fatigue (Functional Assessment of Chronic Illness Therapy-Fatigue [FACIT-F] score; 0–52; decrease=improvement). Endpoints included: proportion of pts in SDAI remission and pts with HAQ-DI response (decrease from IP Day [D]1 in HAQ-DI ≥0.30); adjusted mean change (adMC) from D-E D1 in HAQ-DI, SF-36 PFS or FACIT-F to D-E Wk 48. adMCs were estimated using a mixed effect model with repeated measures.

Results:

147 ABA + MTX-treated pts were re-randomised in the D-E period. Across re-randomised arms, the range of mean scores was 1.87–2.52 for SDAI and 0.18–0.30 for HAQ-DI at entry into D-E period (D-E D1). 74% of pts receiving ABA QW + MTX maintained SDAI remission at D-E Wk 48 (Fig 1); this proportion was higher than in the ABA withdrawal and ABA QW + MTX PBO arms. Pts continuing ABA QW + MTX maintained HAQ-DI response during D-E (Fig 1), but by D-E Wk 48 the proportion of pts with HAQ-DI response in the ABA withdrawal arm declined by 30%. At D-E Wk 48, a small numerical decrease (adMC –0.04) in HAQ-DI was observed in the ABA QW + MTX arm; increases were seen in the withdrawal (adMC 0.26) and ABA QW + MTX PBO arms (adMC 0.16). By D-E Wk 48, SF-36 PFS increased (adMC 1.68) in the ABA QW + MTX arm but decreased in the withdrawal (adMC –3.34) and ABA QW + MTX PBO (adMC –1.45) arms. FACIT-F score increased during D-E in all arms, but the increase at D-E Wk 48 was lower in the ABA QW + MTX arm (adMC 0.79) vs the withdrawal (adMC 4.12) and ABA QW + MTX PBO (adMC 2.41) arms. Similar trends were seen for other PROs including Work Productivity and Activity Impairment-RA; while activity impairment remained stable in the ABA QW + MTX arm, there was a trend for worsening in the withdrawal arm.

Conclusion:

In the AVERT-2 D-E period, continued combination therapy (abatacept + MTX) resulted in maintenance of benefits on PROs, particularly physical functioning, in seropositive pts with early RA. D-E of abatacept followed by complete withdrawal was associated with the greatest loss of remission as well as worsening of PROs. The PRO results corresponded well to the maintenance of clinical (SDAI) remission.

References:

[1]Emery P, et al. ACR 2018; San Diego, USA: Poster 563.

[2]Emery P, et al. ACR 2019; Atlanta, USA: Poster 1423.

Acknowledgments:

Joanna Wright (medical writing, Caudex; funding: Bristol-Myers Squibb)

Disclosure of Interests:

Paul Emery Grant/research support from: AbbVie, Bristol-Myers Squibb, Merck Sharp & Dohme, Pfizer, Roche (all paid to employer), Consultant of: AbbVie (consultant, clinical trials, advisor), Bristol-Myers Squibb (consultant, clinical trials, advisor), Lilly (clinical trials, advisor), Merck Sharp & Dohme (consultant, clinical trials, advisor), Novartis (consultant, clinical trials, advisor), Pfizer (consultant, clinical trials, advisor), Roche (consultant, clinical trials, advisor), Samsung (clinical trials, advisor), Sandoz (clinical trials, advisor), UCB (consultant, clinical trials, advisor), Yoshiya Tanaka Grant/research support from: Asahi-kasei, Astellas, Mitsubishi-Tanabe, Chugai, Takeda, Sanofi, Bristol-Myers, UCB, Daiichi-Sankyo, Eisai, Pfizer, and Ono, Consultant of: Abbvie, Astellas, Bristol-Myers Squibb, Eli Lilly, Pfizer, Speakers bureau: Daiichi-Sankyo, Astellas, Chugai, Eli Lilly, Pfizer, AbbVie, YL Biologics, Bristol-Myers, Takeda, Mitsubishi-Tanabe, Novartis, Eisai, Janssen, Sanofi, UCB, and Teijin, Vivian Bykerk: None declared, Thomas Huizinga Grant/research support from: Ablynx, Bristol-Myers Squibb, Roche, Sanofi, Consultant of: Ablynx, Bristol-Myers Squibb, Roche, Sanofi, Gustavo Citera Grant/research support from: AbbVie, Amgen, Eli Lilly, Gema, Genzyme, Novartis and Pfizer Inc, Consultant of: AbbVie, Amgen, Eli Lilly, Gema, Genzyme, Novartis and Pfizer Inc, Clifton Bingham Grant/research support from: Bristol-Myers Squibb, Consultant of: Bristol-Myers Squibb, Subhashis Banerjee Shareholder of: AbbVie, Bristol-Myers Squibb, Lily, Pfizer, Employee of: Bristol-Myers Squibb (current); AbbVie, Lily, Pfizer (past), Sean Connolly Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Joe Zhuo Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Robert Wong Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Kuan-Hsiang Gary Huang Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Karissa Lozenski Employee of: Bristol-Myers Squibb, Yedid Elbez Consultant of: Bristol-Myers Squibb, Roy Fleischmann Grant/research support from: AbbVie, Akros, Amgen, AstraZeneca, Bristol-Myers Squibb, Boehringer, IngelhCentrexion, Eli Lilly, EMD Serono, Genentech, Gilead, Janssen, Merck, Nektar, Novartis, Pfizer, Regeneron Pharmaceuticals, Inc., Roche, Samsung, Sandoz, Sanofi Genzyme, Selecta, Taiho, UCB, Consultant of: AbbVie, ACEA, Amgen, Bristol-Myers Squibb, Eli Lilly, Gilead, GlaxoSmithKline, Novartis, Pfizer, Sanofi Genzyme, UCB

FRI0090 MAINTENANCE OF CLINICAL RESPONSE WITH ABATACEPT IN COMBINATION WITH MTX IN INDIVIDUAL PATIENTS WITH EARLY RA WHO ARE MTX-NAÏVE AND ANTI-CITRULLINATED PROTEIN ANTIBODY (ACPA)+: RESULTS FROM THE INDUCTION PERIOD OF AVERT-2, A RANDOMISED PHASE IIIB STUDY

Background:

In the 56-wk induction period (IP) of the Phase IIIbAssessingVeryEarlyRATreatment (AVERT)-2 trial (NCT02504268), more patients (pts) achieved SDAI remission (≤3.3) with abatacept (ABA) + MTX vs ABA placebo (PBO) + MTX at IP Wk 52.1It is unknown whether each individual pt within a treatment (Tx) group achieves and sustains the same efficacy endpoints at all time points during the IP.

Objectives:

To investigate whether ABA effectiveness is sustained by individual pts who achieved SDAI remission (≤3.3), SDAI low disease activity (LDA; >3.3–11), DAS28 (CRP) <2.6, ACR50/70 response or Boolean remission at IP Wk 24 (AVERT-2 primary endpoint) and both Wks 40 and 52 (Wks 40/52).

Methods:

Pts were randomised 3:2 to blinded SC ABA (125 mg/wk) + MTX or ABA PBO + MTX induction Tx for 56 wks. Key inclusion criteria: age ≥18 yrs; RA diagnosis (ACR/EULAR 2010 criteria); RA duration ≤6 mos; SDAI >11; ACPA+; CRP >3 mg/L or ESR ≥28 mm/h; TJC ≥3 and SJC ≥3; DMARD naïve. Response rates were investigated by Tx arm in the cohort 1 analysis population (all randomised pts treated in the IP [intent-to-treat analysis]).

Results:

Of randomised cohort 1, 752 pts were treated during the IP: 451 with ABA + MTX and 301 with ABA PBO + MTX. Baseline characteristics were similar across Tx arms.1Stringent SDAI remission endpoint at IP Wk 24 was achieved by 22% of ABA + MTX-treated pts; of these, 56% sustained SDAI remission at IP Wks 40/52 (Table). A similar proportion of ABA + MTX-treated pts achieved (17%) and sustained (58%) Boolean remission at IP Wks 24 and 40/52. At IP Wk 24, 42% of ABA + MTX-treated pts achieved DAS28 (CRP) <2.6 and 74% sustained DAS28 (CRP) <2.6 to IP Wks 40/52; a high proportion of patients sustained ACR50/70 responses at IP Wks 40/52 (83% and 79%, respectively). A lower proportion of pts sustained SDAI LDA to IP Wks 40/52 vs other endpoints (Table). Most efficacy endpoints were achieved by fewer pts who received ABA PBO + MTX than ABA + MTX (Table); among responders in this Tx group, fewer sustained remission at Wks 40/52, which correlates with a higher proportion of pts sustaining SDAI LDA at Wks 40/52 with ABA PBO + MTX than ABA + MTX.

Conclusion:

The majority of individual pts with RA who achieved clinically stringent endpoints such as SDAI remission, DAS28 (CRP) <2.6 or Boolean remission, as well as clinically meaningful endpoints such as ACR50/70 at IP Wk 24 with weekly SC abatacept, sustained their responses to Wks 40/52. The high proportion of patients achieving early stringent remission and response to SC abatacept by individual pts may be indicative of sustained efficacy over time.

References:

[1]Emery P, et al. ACR 2018; San Diego, USA: Poster 563.

Table .

Proportion of Pts With Response at IP Wk 24 Who Also Achieved Remission at Wks 40/52

EndpointResponders at IP Wk 24, n (%)Responders at IP Wk 24 and Wks 40/52, n/N (%)ABA + MTX(n=451)ABA PBO + MTX(n=301)ABA + MTX*ABA PBO + MTX*SDAI remission (≤3.3)100 (22)40 (13)56/100 (56)17/40 (43)SDAI low disease activity (>3.3–11)167 (37)82 (27)46/167 (28)32/82 (39)DAS28 (CRP) <2.6188 (42)78 (26)139/188 (74)43/78 (55)ACR50 response†260 (58)125 (42)215/260 (83)92/125 (74)ACR70 response†156 (35)66 (22)123/156 (79)42/66 (64)Boolean remission76 (17)29 (10)44/76 (58)8/29 (28)

*% based on number of pts within each Tx group who achieved response at IP Wk 24 (denominator);†Response at IP Wks 24 and 52

Acknowledgments:

Lola Parfitt (medical writing, Caudex; funding: Bristol-Myers Squibb)

Disclosure of Interests:

Paul Emery Grant/research support from: AbbVie, Bristol-Myers Squibb, Merck Sharp & Dohme, Pfizer, Roche (all paid to employer), Consultant of: AbbVie (consultant, clinical trials, advisor), Bristol-Myers Squibb (consultant, clinical trials, advisor), Lilly (clinical trials, advisor), Merck Sharp & Dohme (consultant, clinical trials, advisor), Novartis (consultant, clinical trials, advisor), Pfizer (consultant, clinical trials, advisor), Roche (consultant, clinical trials, advisor), Samsung (clinical trials, advisor), Sandoz (clinical trials, advisor), UCB (consultant, clinical trials, advisor), Yoshiya Tanaka Grant/research support from: Asahi-kasei, Astellas, Mitsubishi-Tanabe, Chugai, Takeda, Sanofi, Bristol-Myers, UCB, Daiichi-Sankyo, Eisai, Pfizer, and Ono, Consultant of: Abbvie, Astellas, Bristol-Myers Squibb, Eli Lilly, Pfizer, Speakers bureau: Daiichi-Sankyo, Astellas, Chugai, Eli Lilly, Pfizer, AbbVie, YL Biologics, Bristol-Myers, Takeda, Mitsubishi-Tanabe, Novartis, Eisai, Janssen, Sanofi, UCB, and Teijin, Vivian Bykerk: None declared, Clifton Bingham Grant/research support from: Bristol-Myers Squibb, Consultant of: Bristol-Myers Squibb, Thomas Huizinga Grant/research support from: Ablynx, Bristol-Myers Squibb, Roche, Sanofi, Consultant of: Ablynx, Bristol-Myers Squibb, Roche, Sanofi, Gustavo Citera Grant/research support from: AbbVie, Amgen, Eli Lilly, Gema, Genzyme, Novartis and Pfizer Inc, Consultant of: AbbVie, Amgen, Eli Lilly, Gema, Genzyme, Novartis and Pfizer Inc, Kuan-Hsiang Gary Huang Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Sean Connolly Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Yedid Elbez Consultant of: Bristol-Myers Squibb, Robert Wong Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Karissa Lozenski Employee of: Bristol-Myers Squibb, Roy Fleischmann Grant/research support from: AbbVie, Akros, Amgen, AstraZeneca, Bristol-Myers Squibb, Boehringer, IngelhCentrexion, Eli Lilly, EMD Serono, Genentech, Gilead, Janssen, Merck, Nektar, Novartis, Pfizer, Regeneron Pharmaceuticals, Inc., Roche, Samsung, Sandoz, Sanofi Genzyme, Selecta, Taiho, UCB, Consultant of: AbbVie, ACEA, Amgen, Bristol-Myers Squibb, Eli Lilly, Gilead, GlaxoSmithKline, Novartis, Pfizer, Sanofi Genzyme, UCB

FRI0576 IDENTIFICATION OF SERUM PROTEIN BIOMARKERS ASSOCIATED WITH RA DISEASE SEVERITY

Background:

RA is a systemic autoimmune disease with heterogeneous manifestation. Recent advances in serum proteomics, such as the SomaScan®platform (SomaLogic, Inc., Boulder, USA), allow for a deeper exploration of the protein biomarkers associated with RA and a better understanding of the molecular aetiology of the disease.

Objectives:

To characterise the differences in baseline serum proteome of patients with RA (enrolled in the Phase IIIb Abatacept vs adaliMumab comParison in bioLogic-naïvERA subjects with background MTX [AMPLE] study)1compared with a healthy population, and to identify serum protein biomarkers associated with disease severity and radiographic progression.

Methods:

Patients in the AMPLE study had an inadequate response to MTX and were naïve to biologic DMARDs. Protein abundance was assessed in baseline serum samples from 440 AMPLE study patients and 123 healthy individuals with matching demographics using the SomaScan®platform, with 5000+ slow off-rate modified aptamers and up to 8 log of dynamic range.2Differential abundance testing was performed using linear models to identify differences in protein abundance in patients with RA vs healthy individuals. A separate analysis using a linear model was conducted in only the patients with RA to identify the proteins associated with DAS28 (CRP) and TSS. Pathway analyses were performed for proteins significantly (false discovery rate-adjusted p value <0.05) associated with RA and the disease severity measurements to identify over-representation of the molecular pathways.

Results:

Compared with healthy individuals, >2000 serum proteins were significantly differentially expressed in patients with RA, including many proteins that have been associated with RA (e.g. serum amyloid A [SAA], CRP) and complement. Most of the protein expression differences were of small magnitude (fold change <2). Proteins that were differentially expressed between patients with RA and healthy individuals were enriched in interleukin signalling, neutrophil degranulation, platelet activation/degranulation and extracellular matrix organisation pathways. DAS28 (CRP) was significantly associated with several biomarkers, including SAA, fibrinogen and CRP; in general, proteins associated with DAS28 (CRP) were most strongly enriched in the platelet activation/degranulation pathways (Figure 1), also seen in patients with RA vs healthy individuals. Additionally, many proteins were significantly associated with TSS, including SAA, matrix metalloproteinase-3 and cartilage acidic protein 1. Here, the proteins were most strongly enriched in the extracellular matrix remodelling pathways (Figure 2).

Conclusion:

Our study revealed that thousands of serum proteins are differentially expressed and several pathways are dysregulated between patients with RA and healthy individuals. Additional pathways were identified that reflect disease severity, including joint damage, distinct from those pathways associated with the disease. The SomaScan®platform provides a unique proteomic tool with a wide dynamic range for the identification of serum protein biomarkers associated with RA and disease severity. Proteomic signatures should be considered in clinical trials to better understand disease pathogenesis and predict risk in response to treatment.

References:

[1]Schiff M, et al.Ann Rheum Dis2014;73:86–94.

[2]Gold L, et al.PLoS One2010;5:e15004.

Acknowledgments:

Rachel Rankin (medical writing, Caudex; funding: Bristol-Myers Squibb)

Disclosure of Interests:

David Galbraith Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Minal Caliskan Employee of: Bristol-Myers Squibb, Omar Jabado Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Sarah Hu Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Roy Fleischmann Grant/research support from: AbbVie, Akros, Amgen, AstraZeneca, Bristol-Myers Squibb, Boehringer, IngelhCentrexion, Eli Lilly, EMD Serono, Genentech, Gilead, Janssen, Merck, Nektar, Novartis, Pfizer, Regeneron Pharmaceuticals, Inc., Roche, Samsung, Sandoz, Sanofi Genzyme, Selecta, Taiho, UCB, Consultant of: AbbVie, ACEA, Amgen, Bristol-Myers Squibb, Eli Lilly, Gilead, GlaxoSmithKline, Novartis, Pfizer, Sanofi Genzyme, UCB, Michael Weinblatt Grant/research support from: Amgen, Bristol-Myers Squibb, Crescendo, Lily, Sanofi/Regeneron, Consultant of: AbbVie, Amgen, Bristol-Myers Squibb, Crescendo, Gilead, Horizon, Lily, Pfizer, Roche, Sean Connolly Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Michael A Maldonado Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Sheng Gao Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb

FRI0038 THE RELATIONSHIP BETWEEN ABATACEPT EXPOSURE AND EFFICACY MEASURES IN EARLY MTX-NAIVE ANTI-CITRULLINATED PROTEIN ANTIBODY-POSITIVE PATIENTS WITH RA DURING THE DE-ESCALATION PERIOD OF A PHASE IIIB STUDY

Background:

Although EULAR/ACR guidelines suggest tapering biologic treatment for RA following sustained remission in patients (pts), specific de-escalation (DE) regimens are not defined. The Phase IIIb Assessing Very Early Rheumatoid arthritis Treatment (AVERT)-2 trial (NCT02504268) is evaluating SC abatacept (ABA) + MTX versus ABA placebo (PBO) + MTX in Anti-Citrullinated Protein Antibody (ACPA)-positive pts with early (ACR/EULAR 2010 criteria; disease duration ≤6 mths), active RA (SDAI >11). AVERT-2 was designed to investigate achievement of SDAI remission and a clinically meaningful dose DE strategy among pts in sustained remission who completed induction with ABA + MTX. In moderately to severely active RA and JIA patients, a relationship between ABA Cmin and efficacy was observed. Therefore, this analysis in very early RA patients, reports on the pharmacokinetics (PK) and immunogenicity of ABA and the maintenance of remission during the DE period of AVERT-2.

Objectives:

To assess the relationship between changes in ABA exposure and the maintenance of remission and the effect of immunogenicity on exposure during the DE period of AVERT-2.

Methods:

Pts received blinded SC ABA (125 mg once wkly [QW]) + MTX or ABA PBO + MTX induction treatment for 56 wks. Pts who completed induction with ABA + MTX and had sustained SDAI remission (≤3.3 at Wks 40 and 52) were re-randomized 1:1:1 to ABA QW + MTX for 48 wks (Arm C), ABA every other wk (EOW) + MTX for 24 wks followed by ABA PBO + MTX for 24 wks (Arm D), or ABA QW + MTX PBO for 48 wks (Arm E) in the DE period. ABA trough (Cmin) and anti-drug antibody (ADA) samples were collected in all subjects during the DE period. Serum ABA concentrations and ADA were measured using a validated enzyme immunoassay method and an electrochemiluminescence assay, respectively. Efficacy endpoints included change from DE Day 1 in SDAI score, HAQ-DI score, Physician’s Global Assessment (PhGA), and tender (TJC) and swollen (SJC) joint counts. The relationship between ABA Cmin and efficacy endpoints were assessed. Additionally, the impact of immunogenicity on ABA Cmin was explored.

Results:

Mean ABA Cmin values remained stable throughout the DE period for subjects in Arms C and E. ABA Cmin values decreased by ~50% in subjects in Arm D for the first 24 weeks from the start of DE and were ~0 for weeks 24-48 consistent with the change in the frequency of ABA dosing from EOW to ABA withdrawal (Figure 1 top).

Figure 1:

Mean (SD) ABA Cmin values (top) and Mean Change From Baseline in SDAI (bottom) in Subjects in DE Arm C (ABA QW + MTX), D (ABA EOW + MTX followed by ABA placebo + MTX), and E (ABA QW + MTX placebo)

The incidence of immunogenicity appeared to increase upon withdrawal of ABA in Arm D. ADA formation did not appear to affect ABA Cmin, as ABA Cmin remained consistent between pts with and without ADA.

Upon withdrawal of ABA in Arm D, there appeared to be an increase in the mean change from baseline (Day 1 of DE) in SDAI over time, which followed a similar time course as the washout of ABA (Figure 1 bottom). Similar results were observed for other efficacy endpoints such as HAQ-DI, PhGA, TJC, and SJC.

Conclusion:

The PK data in these early onset, MTX-naive, ACPA+ RA pts correlated well with the maintenance of remission in Arms A and E. Tapering of ABA from EOW to MTX only in Arm D results in a corresponding decrease in ABA Cmin, an increase in positive antibody response, and loss of remission.

References:

[1]Emery et. al. ACR [Abstract L11]. Nov. 2019. Atlanta GA USA

[2]Li et. al. J Clin Pharmacol. Vol 59(2). Feb 2019.

Disclosure of Interests:

Yash Gandhi Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Sean Connolly Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Kuan-Hsiang Gary Huang Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Robert Wong Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Shannon Chilewski Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Bindu Murthy Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb

The mechanical responses of advecting cells in confined flow

Fluid dynamics have long influenced cells in suspension. Red blood cells and white blood cells are advected through biological microchannels in both the cardiovascular and lymphatic systems and, as a result, are subject to a wide variety of complex fluidic forces as they pass through. In vivo, microfluidic forces influence different biological processes such as the spreading of infection, cancer metastasis, and cell viability, highlighting the importance of fluid dynamics in the blood and lymphatic vessels. This suggests that in vitro devices carrying cell suspensions may influence the viability and functionality of cells. Lab-on-a-chip, flow cytometry, and cell therapies involve cell suspensions flowing through microchannels of approximately 100-800  μ m. This review begins by examining the current fundamental theories and techniques behind the fluidic forces and inertial focusing acting on cells in suspension, before exploring studies that have investigated how these fluidic forces affect the reactions of suspended cells. In light of these studies' findings, both in vivo and in vitro fluidic cell microenvironments shall also be discussed before concluding with recommendations for the field.

P4784Efficacy and safety of dronedarone by duration of atrial fibrillation history: a post-hoc analysis of the ATHENA trial

Background

Atrial fibrillation (AF) is known to progress over time and the effectiveness of antiarrhythmic therapy may vary based on the duration of a patient's AF history. Outcomes with dronedarone (DRO) based on duration of AF/atrial flutter (AFL) history have not been previously characterized.

Purpose

To evaluate the efficacy and safety of DRO by time since first known AF/AFL episode in patients studied in the ATHENA trial.

Methods

2859 (61.8%) patients from ATHENA with documented first known AF/AFL episode (of 4628 total patients randomized) were included in the analysis. Among these patients, first AF/AFL episode was reported at <3 months (shorter history), 3 to <24 months (intermediate), and ≥24 months (longer) in 1296 (45.3%), 845 (29.6%) and 718 (25.1%) patients, respectively. AF/AFL recurrence was evaluated in patients in sinus rhythm at baseline by ECG during study visits or symptom recurrence.

Results

Demographics (age, sex) were similar across all groups. Patients with longer AF/AFL history tended to have higher prevalence of coronary heart disease and structural heart disease; and were more likely to have AF/AFL (by 12-lead ECG) at baseline (30%) compared to 26% and 16% for intermediate and shorter history groups. Patients with a longer AF history likely had a prior ablation for AF/AFL (7%) vs patients with an intermediate (2%) or shorter AF/AFL history (1%), and more likely required cardioversion during the study (24%) vs intermediate (17%) and shorter history groups (11%). Outcomes and efficacy are reported in Table 1. Rates of treatment-emergent adverse events (TEAEs), serious TEAEs, permanent drug discontinuations, and deaths were similar across all AF/AFL groups.

Table 1. Outcomes and efficacy summary Relative Risk, dronedarone (DRO) vs placebo (PBO)1 (95% CI)1,2 AF/AFL <3 months AF/AFL 3 to <24 months AF/AFL ≥24 months PBO (n=626) DRO (n=670) PBO (n=429) DRO (n=416) PBO (n=363) DRO (n=355) First CV hospitalization3 or death (any cause) 0.79 (0.65, 0.96) 0.72 (0.56, 0.92) 0.84 (0.66, 1.07) First CV hospitalization 0.78 (0.64, 0.96) 0.70 (0.55, 0.91) 0.82 (0.63, 1.05) Death (any cause) 0.82 (0.54, 1.24) 0.85 (0.43, 1.68) 1.13 (0.61, 2.10) First AF/AFL recurrence4 0.80 (0.65, 0.97) 0.67 (0.53, 0.84) 0.81 (0.65, 1.02) 1Cox regression model. 2On study period, all randomized patients. 3Main reason was AF/other supraventricular rhythm disorders. 4On selected patients in sinus rhythm at baseline (AF/AFL <3 months: PBO n=514, DRO n=529; 3 to <24 months: PBO n=288, DRO n=312; ≥24 months: PBO n=252, DRO n=250). CV = Cardiovascular.

Conclusions

Nearly half the patients in ATHENA had a shorter history (<3 months) of AF/AFL prior to randomization. Patients with a longer history of AF/AFL had a greater burden of AF/AFL based on baseline rhythm status, ablation history, and cardioversions required post randomization. Despite these differences, clinical outcomes, efficacy, and safety of DRO appeared to be generally consistent irrespective of duration of AF/AFL history.

Acknowledgement/Funding

Sanofi, New York, New York, United States of America

Leydig Cell Hyperplasia Mimicking a Testicular Tumour in a Patient with Klinefelter Syndrome

Background

Klinefelter syndrome (KS) is the most common sex-chromosomal disorder in males. Frequently under-recognized, it occurs in 1 in 500-600 male births. It is caused by the inheritance of at least one additional X chromosome from either parent. Patients often have uncommon or atypical malignancies.

Patient

We describe the case of a 35-year-old man with 47XXY KS and previous cryptorchidism, presenting with a painful testicular mass. Histology confirmed Leydig cell hyperplasia.

Discussion

Cryptorchidism is an established risk factor for testicular tumours and occurs six times more commonly in KS than in the general population. Despite this, large epidemiological studies have shown a reduced burden of testicular cancer in these patients. The presentation of a hypoechoic lesion on ultrasound will prompt consideration of testicular tumours, however orchalgia represents an atypical presentation. In patients with KS, Leydig cell hyperplasia is a much more common entity and should be considered early in the differential diagnosis.

LEARNING POINTS

The differential diagnosis of a testicular mass in Klinefelter syndrome includes malignancy and nodular Leydig cell hyperplasia.Diagnosis can be challenging, both radiologically and histologically.Orchalgia is atypical in Leydig cell hyperplasia.

A two-step method for variable selection in the analysis of a case-cohort study

Background

Accurate detection and estimation of true exposure-outcome associations is important in aetiological analysis; when there are multiple potential exposure variables of interest, methods for detecting the subset of variables most likely to have true associations with the outcome of interest are required. Case-cohort studies often collect data on a large number of variables which have not been measured in the entire cohort (e.g. panels of biomarkers). There is a lack of guidance on methods for variable selection in case-cohort studies.

Methods

We describe and explore the application of three variable selection methods to data from a case-cohort study. These are: (i) selecting variables based on their level of significance in univariable (i.e. one-at-a-time) Prentice-weighted Cox regression models; (ii) stepwise selection applied to Prentice-weighted Cox regression; and (iii) a two-step method which applies a Bayesian variable selection algorithm to obtain posterior probabilities of selection for each variable using multivariable logistic regression followed by effect estimation using Prentice-weighted Cox regression.

Results

Across nine different simulation scenarios, the two-step method demonstrated higher sensitivity and lower false discovery rate than the one-at-a-time and stepwise methods. In an application of the methods to data from the EPIC-InterAct case-cohort study, the two-step method identified an additional two fatty acids as being associated with incident type 2 diabetes, compared with the one-at-a-time and stepwise methods.

Conclusions

The two-step method enables more powerful and accurate detection of exposure-outcome associations in case-cohort studies. An R package is available to enable researchers to apply this method.

A Life-Saving Palsy: Hereditary Neuropathy with Liability to Pressure Palsies (HNPP) Presenting As Hand Weakness during Cardiopulmonary Resuscitation (CPR) Training

Aim To describe a case of acute and transient hand weakness that developed during cardiopulmonary resuscitation (CPR) training. Hereditary neuropathy with liability to pressure palsies (HNPP) should be considered in patients with recurrent, painless motor or sensory neuropathies at sites of peripheral nerve compression. Methods Nerve conduction studies confirmed neuropraxia of the distal ulnar nerve with a mild background demyelinating peripheral neuropathy. Results A positive family history emerged and HNPP was confirmed by genetic testing. HNPP is most reliably diagnosed by molecular testing for peripheral myelin protein 22 (PMP22) gene deletion or point mutation on chromosome 17p11.2. Conclusion CPR, a procedure carried out by medical professionals on a daily basis, is a high-energy manual task and provides multiple opportunities for nerve compression. This case demonstrates the importance of having a high index of clinical suspicion of this disorder in patients. Recognising a diagnosis of HNPP may prevent unnecessary surgical decompression.

Iatrogenic Bowel Injury at Exchange of Supra-Pubic Catheter

Suprapubic catheter insertion and exchange is a common urological procedure, but it is not without risks and complications. While bowel perforation is a recognised complication at suprapubic catheter insertion, it is not commonly reported at suprapubic catheter exchange. We report our experience of recognition, diagnosis and subsequent successful management of the most important complication related to suprapubic catheters.

Calcific myonecrosis: diagnostic dilemma

Calcific myonecrosis is a rare benign condition affecting mainly the muscles of a single leg compartment. It is thought to follow a history of trauma with a latent period of years. Patients present with a slowly growing mass. Differential diagnosis from a malignant tumour can be made from the history and the distinctive radiographical features of a fusiform lesion with predominantly peripheral calcifications. Magnetic resonance imaging may be necessary to confirm the diagnosis; treatment is largely symptomatic.