Sudhakar Sridharan

The Biomarkers of Lupus Disease Study: A Bold Approach May Mitigate Interference of Background Immunosuppressants in Clinical Trials

Molecular medicine raised expectations for strategically targeted biologic agents in systemic lupus erythematosus (SLE), but clinical trial results have been disappointing and difficult to interpret. Most studies add investigational agents to various, often effective, standard therapy immunosuppressants used at baseline, with unknown treatment interactions. Eliminating polypharmacy in trials of active lupus remains controversial. We undertook the Biomarkers of Lupus Disease study to test withdrawal of immunosuppressants as a novel approach to rendering SLE trials interpretable.

Local rhBMP-12 on an Absorbable Collagen Sponge as an Adjuvant Therapy for Rotator Cuff Repair— A Phase 1, Randomized, Standard of Care Control, Multicenter Study Safety and Feasibility

Background: Recombinant human bone morphogenetic protein–12 (rhBMP-12) has been shown to induce tendon and ligament formation in rats and to improve tendon healing; however, the safety and feasibility of implanting rhBMP-12/absorbable collagen sponge (ACS) in humans are not known. Purpose: To investigate the safety and feasibility of rhBMP-12 on an ACS as an adjuvant therapy in open rotator cuff repair. Study Design: Randomized controlled trial; Level of evidence, 2. Methods: This study consisted of 20 patients with full-thickness rotator cuff tears. Patients were randomized either to standard of care (SOC) treatment (open rotator cuff repair) or to receive 0.015 mg/mL rhBMP-12/ACS and SOC treatment during their open rotator cuff repair (rhBMP-12/ACS group) at a rate of 1/4 SOC/rhBMP-12/ACS. The feasibility of implanting the product and the safety of the product were evaluated during the 1-year follow-up period. The evaluation involved up to 10 postoperative visits, which included physical examinations, radiographs, computed tomography (CT) scans, magnetic resonance imaging (MRI) scans with an emphasis on heterotopic ossification (HO), pharmacokinetics, immunogenicity, laboratory evaluations, and local and systemic adverse events at specified time points. Results: Small amounts of HO were seen on follow-up CT scans in 10 of 16 patients in the rhBMP-12/ACS group and in 2 of 3 patients in the SOC group. HO did not increase at 26 weeks and was not associated with any adverse events or unsatisfactory clinical outcomes. Pharmacokinetics demonstrated that circulating levels of rhBMP-12 were not detectable after administration. Five of 16 patients showed a postoperative immunogenic response but did not show any correlating adverse events. Complete healing of the rotator cuff was observed in 14 of 16 patients; 2 of 16 imaging results could not be analyzed because of artifacts in the rhBMP-12 group on MRI scans. In the SOC group, 1 of 4 patients showed a retear at 12 weeks after surgery. Conclusion: The use of rhBMP-12/ACS has been shown to be feasible and safe in a concentration of 0.015 mg/mL when used in open rotator cuff repair. Higher dose concentrations of rhBMP-12 should be evaluated in the future to evaluate their safety and potential to increase rotator cuff healing after open surgical repair.

OP0185 Significant Clinical Improvement and Reduction of Severe Flares Following Administration of an IL-6 Monoclonal Antibody in Systemic Lupus Erythematosus (SLE) Subjects with High Disease Activity

Background PF-04236921 is a fully human monoclonal antibody (mAb) that binds to circulating IL-6 and neutralizes its activity. This may be beneficial in reducing the disease manifestations of active SLE. Objectives To assess the efficacy, safety, and tolerability of PF-04236921 in subjects with active SLE. Methods 183 subjects with active SLE (SLEDAI ≥6 and ≥1 BILAG 2004 A or ≥2 Bs) received 3 doses of PF-04236921 (10, 50, or 200mg) or placebo given subcutaneously every 8 wks. The primary endpoint was the proportion of SLE Responder Index 4 (SRI-4) responders at Wk 24 using a generalized linear mixed model. The BILAG-based Combined Lupus Assessment (BICLA), frequency of severe flares, and SF-36 were also evaluated. Results The majority of subjects were female (91.8%), mean age 40.4, with musculoskeletal and mucocutaneous organ system involvement. Baseline demographics were similar across groups. At Wk 24, there were more responders in the 10mg group vs placebo for the SRI (p=0.076) and BICLA (p=0.026). Improvement in the SF-36 PCS domain was also noted for the 10mg group vs placebo (p=0.092). For the 50mg group there were no significant differences vs placebo for the SRI (p=0.528) or BICLA (p=0.1). A post-hoc subgroup analysis was completed in subjects with high baseline disease activity [SLEDAI ≥10, detectable anti-dsDNA, low complement, or prednisone >7.5 mg/day (enriched population)]. In this subgroup, a significant effect size was observed for the SRI, BICLA, and SF-36 PCS domain for the 10mg group vs placebo. There was also a significant reduction in the frequency of severe SELENA-SLEDAI Flare Index (SFI) flares for the combined 10 and 50mg groups vs placebo for both the broad (p=0.004) and enriched populations (p=0.004). Adverse events (AEs), infectious AEs, and discontinuations due to AEs were comparable across groups. The rate of SAEs was highest in the placebo and 200mg groups and the rate of serious infections was highest in the 200mg group. There were 4 deaths; 3 in 200mg [cardiorespiratory arrest, urosepsis with pulmonary embolism (PE), and disseminated tuberculosis] and 1 in 10mg (suspected PE); further dosing of 200mg was subsequently terminated. Conclusions An efficacy signal was apparent in the broad population following administration of an IL-6 mAb notably with regard to severe flare reduction. Greater efficacy was observed across several key parameters for the 10mg group in the enriched population compared to the broad population. The safety profile with 10 and 50mg doses appeared acceptable for both the broad and enriched population; dosing with 200mg was terminated due to safety concerns. Disclosure of Interest J. Smolen Grant/research support from: Abbvie, Janssen, MSD, Pfizer Inc, Roche, UCB, Consultant for: Abbvie, Amgen, Astra-Zeneca, Astro, Celgene, GSK, Janssen, Eli-Lilly, Medimmune, MSD, Novartis-Sandoz, Novo-Nordisk, Pfizer Inc, Roche, Samsung, Sanofi-Aventis, UCB, S. Popa: None declared, I. Szombati: None declared, D. Wallace: None declared, M. Petri Consultant for: Pfizer Inc., P. Lipsky Consultant for: Pfizer Inc., J. Merrill Consultant for: Pfizer Inc., V. Strand Consultant for: Abbvie, Amgen, Anthera, Astra-Zeneca, Biogen Idec, Bristol-Myers Squibb, Genentech, GSK, Janssen, Merck Serono, Novartis, Pfizer Inc, Sanofi-Aventis, Takeda, UCB, P. Healey Employee of: Pfizer Inc., C. Li Employee of: Pfizer Inc., J. Christensen Employee of: Pfizer Inc., A. Diehl Employee of: Pfizer Inc., J. Beebe Employee of: Pfizer Inc., M. Vincent Employee of: Pfizer Inc., J. Wajdula Employee of: Pfizer Inc., S. Sridharan Employee of: Pfizer Inc.

THU0046 Predictive Modeling of Immunologic and Inflammatory Markers of Impending Disease Flare in Patients with Systemic Lupus Erythematosus not Taking Immunosuppressive Medications

Background Systemic lupus erythematosus (SLE) is a clinically heterogeneous disorder with a waxing and waning clinical course. Reliable markers of clinical disease flare have been difficult to identify, impeding the selection of optimal therapies, which leads to suboptimal disease control and cumulative organ damage. Objectives Our goal was to identify immune markers associated with impending vs delayed flare in SLE patients in the absence of confounding immunosuppressive medications. Methods As part of the Biomarkers of Lupus Disease (BOLD) study, 41 SLE patients with non-organ-threatening, moderately severe disease activity were enrolled, background immunosuppressants (IS) discontinued, intramuscular steroids given until disease suppression, and followed until clinical flare. Patients met ≥4 ACR SLE criteria and had SLEDAI ≥6 or BILAG ≥2 B or 1 A scores at baseline. Samples were procured at baseline, time of disease suppression, and serially until flare (defined as requiring new treatment and ≥1 new BILAG B or ≥4 point SLEDAI increase). Cellular immunophenotyping markers and 52 soluble mediators were measured using xMAP multiplex technology or sandwich ELISA. Random forest was used to generate predictive models and applied as described [1]. Results Forty SLE patients flared within 24 weeks, with 21 flaring within 60 days (early) and 13 flaring later than 90 days (late) after stopping background IS. Patients who flared early were more likely to be of African-American descent, while Native American patients were more likely to flare late. At baseline those who flared early had higher levels of bicarbonate, increased frequencies of monocytes and neutrophils expressing the activated conformation of CD11b, monocytes (p=0.028) and neutrophil (p=0.002), as well as greater frequency of activated naïve B cells. SLE patients who flared late had higher baseline plasma levels of IL-1RA (p=0.03) and TNFRI (p=0.04). At the flare visit this group had higher levels of BLyS (p=0.01), IL-7 (p=0.03), and IFNg (p=0.04). Predictive models were generated and tested using random forest models. The best prediction model for the course of flare based on three immunophenotyping parameters achieved 87% accuracy with a positive predictive value of 0.78 (95% CI, 0.52 – 0.94) and a negative predictive value of 0.80 (0.44 – 0.97). The model indicates that absence of the activated monocyte population (activated CD11bhi) and the activated naïve B cell subpopulation (CD86hi) led to a drastically reduced likelihood of an early flare. Conclusions SLE patients who flare earlier after withdrawal of ineffective immuno-suppressants and transient steroid treatment have increased measures of innate and/or adaptive immune system activation, while SLE patients who flare later have increased evidence of regulatory pathway engagement through shedding of IL-1RA. References Genuer R, et al. Pattern Recogn Lett. 2010;31(14):2225-36. Disclosure of Interest : J. Guthridge: None declared, R. Lou: None declared, S. Kamp: None declared, M. Munroe: None declared, K. Bean: None declared, S. Macwana: None declared, S. Sridharan Employee of: Pfizer Inc, J. Merrill Grant/research support: Pfizer Inc, Consultant for: Pfizer Inc, J. James: None declared DOI 10.1136/annrheumdis-2014-eular.5642

FRI0003 Determination of interferon (IFN) signatures for sle patients may be critical for optimal treatment selection but depends on the genes chosen: report from the bold (biomarkers of lupus disease) study

Background Elevated expression of IFN pathway genes, known as the IFN signature (IS) is found in roughly half of SLE patients1. Various studies have used different IFN genes to define the IS, and different methods to assign patients to “IFN high” or “low” expression groups. Importantly a recent report from the Genentech ROSE study found higher responsiveness to an interferon antagonist in patients with lower IFN expression using a 7 gene set (G-7), suggesting that IS might inform optimal selection of treatments in the future2. Objectives As a step toward understanding the clinical relevance and molecular drivers of the IS, we used data from the BOLD study to test the difference between IS-derived patient groupings derived from different sets of IFN genes. Methods The BOLD study enrolled SLE patients with active disease (minimum SLEDAI of 6 or two BILAG B scores). 41 patients had background immune suppressives withdrawn, were given brief steroids until improvement, then followed with serial samples until disease flare. 62 additional active SLE patients were evaluated only once. RNA expression levels for 329 genes were assayed using TaqMan® Low Density Arrays. 238 SLE patient-visits were partitioned into two groups by unsupervised hierarchical clustering of the expression levels of IFN-related genes. Results Clustering was done separately for 5 gene sets, denoted B-30, P-11, M-20, G-7, and O-3. Two of the gene sets (M-20 and G-7) were 95% and 100% matched to sets used in clinical trials of IFN-inhibiting treatments. Consistent with previous reports, all of the gene sets assigned about 40-50% of visits (96 to 118 patient-visits) to an “IFN high” group characterized by IFN pathway expression that was higher than healthy volunteers. In a cross-sectional analysis using the P-11 gene set, membership in the IFN high group was associated with higher SLEDAI score than IFN low assignment (9.73 vs. 7.70, p<0.0001) and higher TNFSF13B (BLYS/BAFF) gene expression (2.4 fold increase, p=0.0005). Most of the patients followed longitudinally remained in the same group over the course of the study, despite changes of gene expression with disease improvement and flare. IFN group assignments were similar for the B-30 and P-11 gene sets, and also similar among the M-20, G-7, and O-3 gene sets, but differed more across these groups. For instance, 21 patient-visits (9%) were assigned to the IFN high group by the G-7 gene set, but placed in the IFN low group by the P-11 gene set. Conclusions The comparison of IFN group assignments for the same samples, derived using different IFN gene sets, highlights the need for more investigation of the molecular and cellular drivers of IFN gene expression in SLE blood. An optimal IFN gene set, once determined, might improve how patients are selected for targeted therapies in the future. References Baechler et al., PNAS 100(5) 2610-2615 (2003); Kalunian et al., ACR 2012 Washington D.C, Abstract 2622. Disclosure of Interest None Declared

Local rhBMP-12 on an Absorbable Collagen Sponge as an Adjuvant Therapy for Rotator Cuff Repair—A Phase 1, Randomized, Standard of Care Control, Multicenter Study: Part 2—A Pilot Study of Functional Recovery and Structural Outcomes

Background: The high failure rate of rotator cuff repairs requires the development of methods to enhance healing at the tendon-bone junction of the repair site. Purpose: To assess functional recovery and structural outcomes in detail after implanting recombinant human bone morphogenetic protein–12 (rhBMP-12)/absorbable collagen sponge (ACS) as adjuvant treatment during open rotator cuff repair in patients over a 1-year postoperative follow-up. Study Design: Randomized controlled trial; Level of evidence, 2. Methods: A total of 20 patients were randomized into 2 groups, rhBMP-12/ACS and standard-of-care (SOC) control, with 16 and 4 patients, respectively. The patients underwent open repair of a rotator cuff tear at least 2 to 4 cm wide; in the rhBMP-12/ACS group, this was augmented with a bioscaffold containing rhBMP-12. Follow-up assessments were conducted with a 100-mm visual analog scale (VAS) for pain and active and passive ranges of motion (ROMs) including forward flexion, elevation in the scapular plane, abduction, and external rotation at 12, 16, 26, 39, and 52 weeks after surgery; isometric strength in scapular abduction and external rotation at 16, 26, 39, and 52 weeks; and magnetic resonance imaging (MRI) at 12 and 52 weeks. Results: The mean VAS score decreased from 37.9 mm preoperatively to 13.8 mm at week 52, and ROM and isometric strength recovered at week 52 in the rhBMP-12/ACS group. The mean VAS score decreased from 48.3 mm preoperatively to 1.5 mm at week 52, and ROM (excluding external rotation) and isometric strength recovered by week 52 in the SOC control group. Of the 16 patients in the rhBMP-12/ACS group, 14 showed an intact repair at week 12; the MRI scans of the other 2 patients could not be evaluated because of artifacts. In the SOC control group, 1 patient showed repair failure. At week 52, 14 repairs in the rhBMP-12/ACS group and 2 repairs with available MRI scans in the SOC control group remained intact. Conclusion: Functional recovery and structural outcomes in patients in whom rhBMP-12/ACS was used as adjuvant therapy in rotator cuff repair justify conducting future, larger, multicenter, prospective studies. Registration: NCT00936559, NCT01122498 (ClinicalTrials.gov identifier).

FRI0318 Comparison of lupus trial endpoints to a physician-weighted definition of improvement in the biomarkers of lupus disease (BOLD) study suggests improved discrimination using bicla (bilag based composite lupus assessment) vs sri (sle responder index)

Background The choice of composite clinical assessment tools in lupus clinical trials is expanding, but it is important to understand the differences between what these endpoints measure. The SLE Responder Index (SRI) was developed for the successful Phase III belimumab (BLISS) program which defines response as ≥ 4 (SRI-4) or 5 (SRI-5) point decrease in SLEDAI, no new BILAG A (severe disease) or 2 new B (moderate disease) organ scores plus increase in PGA of < 0.3 points (10% of scale). The best treatment corrected difference achieved with SRI-4 were 9.8% (1), and 14.4% (2) in the two phase III BLISS trials. The BICLA was tested in a Phase II study of epratuzumab (EMBLEM) with response defined by at least one grade improvement in all BILAG moderate or severe scores, no new BILAG A or 2 new B scores, no increase in SLEDAI, <10% worsening in PGA and no off-protocol treatment. Optimal treatment corrected differences in this trial was 24.8% (3). A comparison of BICLA and SRI has been reported using EMBLEM data (4), but was complicated by scoring of many 8 point features on SLEDAI which are not common in lupus. BICLA data from the BLISS studies have not been reported. Objectives To compare the SRI and BICLA to a physician-weighted definition of improvement in the BOLD study Methods The BOLD study was designed to test the impact of clinical, biologic and background treatment variables on lupus trials and scoring of 8 point SLEDAI features were rare. 41 patients entered with active disease (minimum SLEDAI of 6 or two BILAG B scores) in a single study center, then background immune suppressives were withdrawn, brief intramuscular steroids given until improvement, and patients followed until they flared. BOLD improvement was defined as either a 4 point drop in SLEDAI or one grade improvement in BILAG and required physician determination of clinically significant improvement. This allowed for simpler quantitative criteria, anchored by clinician judgment. Results At the improving visit, the mean decrease from baseline in PGA was 1.06 ± 0.38 (scale 0-3). Count of responders by SRI and BICLA are shown in the table below with McNemar’s test p-value for comparisons to the BOLD (physician-weighted) definition of improvement. Conclusions The BICLA was more likely to agree with a physician weighted definition of improvement than SRI, and less likely to score a physician designated flare visit as improvement. Differences in treatment efficacy, clinical trial design, and adjudication of trial endpoints may have accounted for the improved discrimination seen between treatment groups in the EMBLEM study (using BICLA) compared to the BLISS studies (using SRI). However, if further validated, these observations from BOLD may be helpful in optimizing the choice of clinical endpoints for future lupus trials. References Navarra SV, et al. Lancet. 2011;377:721–731. Furie R, et al. Arthritis Rheum. 2011;63:3918–3930. Wallace DJ, et al. Ann Rheum Dis 2013;00:1–8. Petri M, et al. ACR 2011; 1378. Disclosure of Interest: None Declared