Serum Tau-A and Tau-C Levels and Their Association with Cognitive Impairment and Dementia Progression in a Memory Clinic Derived Cohort

BACKGROUND

Serum-measured fragments of Tau cleaved by ADAM-10 (Tau-A) and Caspase-3 (Tau-C) have been found linked to change in cognitive function and risk of dementia.

OBJECTIVES

1) To determine the discriminatory abilities of Tau-A, and Tau-C in subjects with either mild cognitive impairment (MCI) due to Alzheimer's disease (AD) or AD dementia compared to a control group. 2) To determine if there is a relation between Tau-A, and Tau-C and established cerebrospinal fluid (CSF) markers of AD- β-Amyloid1-42 (AB42), Phosphorylated-tau-181 (p-tau), and total-tau. 3) To determine if Tau-A and Tau-C are associated with progression rate from MCI due to AD to AD dementia.

DESIGN

Cross-sectional and a substudy using a retrospective cohort design.

SETTING

Memory clinic derived subjects contributing to the Danish Dementia Biobank.

PARTICIPANTS

Cognitively unimpaired subjects (n=49), patients with mild cognitive impairment (MCI) due to AD (n=45), and Alzheimer's dementia (n=52).

MEASUREMENTS

Competitive enzyme-linked immunosorbent assay (ELISA)-measured serum levels of Tau-A, and Tau-C.

RESULTS

The ratio between Tau-A and Tau-C differed between the three groups (p=0.015). Age- and sex-adjusted Tau-A differed between groups with lower ratios being associated with more severe disease (p=0.023). Tau-C was trending towards significant correlation to CSF-levels of AB42 (Pearson correlation coefficient 0.164, p=0.051). Those with Tau-C-levels in the 2nd quartile had a hazard ratio (HR) of 2.91 (95% CI 1.01 - 8.44, p=0.04) of progression compared to those in the 1st quartile. Those in the 3rd quartile was found to have a borderline significant (p=0.055) HR of 2.63 (95% CI 0.98 - 7.05) when compared to those in the lowest quartile.

CONCLUSIONS

Tau-A and the ratio between Tau-A and Tau-C showed significant differences between groups and were correlated to CSF-AB42. Tau-C values in the middle range were associated with faster progression from MCI to dementia. This pilot study adds to the mounting data suggesting serum-measured Tau-A and Tau-C as biomarkers useful in relation to diagnosis and progression rate in AD but need further validation.

Reflections from the OARSI 2022 clinical trials symposium: The pain of OA-Deconstruction of pain and patient-reported outcome measures for the benefit of patients and clinical trial design

OBJECTIVE

Osteoarthritis (OA) drug development is hampered by a number of challenges. One of the main challenges is the apparent discordance between pain and structure, which has had a significant impact on drug development programs and has led to hesitance among stakeholders. Since 2017, the Clinical Trials Symposium (CTS) has been hosted under the Osteoarthritis Research Society International (OARSI) leadership. OARSI and the CTS steering committee yearly invite and encourage discussions on selected special subject matter between regulators, drug developers, clinicians, clinical researchers, biomarker specialists, and basic scientists to progress drug development in the OA field.

METHOD

The main topic for the 2022 OARSI CTS was to elucidate the many facets of pain in OA and to enable a discussion between regulators (Food and Drug Administration (FDA) and the European Medicines Agency (EMA)) and drug developers to clarify outcomes and study designs for OA drug development.

RESULTS

Signs or symptoms indicative of nociceptive pain occur in 50-70% of OA patients, neuropathic-like pain in 15-30% of patients, and nociplastic pain in 15-50% of patients. Weight-bearing knee pain is associated with bone marrow lesions and effusions. There are currently no simple objective functional tests whose improvements correlate with patient perceptions.

CONCLUSIONS

The CTS participants, in collaboration with the FDA and EMA, raised several suggestions that they consider key to future clinical trials in OA including the need for more precise differentiation of pain symptoms and mechanisms, and methods to reduce placebo responses in OA trials.

OP0230 ANTIHISTAMINE USE AND STRUCTURAL PROGRESSION OF KNEE OA: A POST-HOC ANALYSIS OF TWO PHASE III CLINICAL TRIALS

Background

Prior studies indicate that mast cells are involved in chronic inflammation and that their activity in the synovium may contribute to structural progression of osteoarthritis (OA), however the exact role of mast cells in OA remains unclear. Antihistamines act by blocking histamine receptors, and further are found to have anti-inflammatory effects by stabilizing mast cell membranes. Current reports describing antihistamine use in OA patients suggest that antihistamines may reduce development of OA and lead to reduced risk of structural progression.

Objectives

We aimed to investigate whether antihistamine use during a two-year trial period was associated with differences in structural progression of OA, as compared with non-use.

Methods

This is a post-hoc analysis of two large phase III trials investigating oral salmon calcitonin in knee OA (NCT00486434 and NCT00704847). The primary outcome measure was structural progression defined as the change in minimum joint-space width measured by use of x-ray imaging from baseline to Year Two. In these trials, participants reported use of antihistamines, defined as medication coded with the ATC code R06A. In our study, we evaluated differences between groups of participants who reported use of antihistamines, versus those who did not, over the 2-year study period. Secondly, the duration of antihistamine use divided into categories of either no use, 1-49, 50-299 or >300 days of use was investigated to evaluate exposure-response relationships. The effect of use of antihistamines was evaluated using ANCOVA analysis adjusting for age, sex, BMI, and baseline JSW.

Results

Of a total study population of 2,206 participants, 1,485 completed the trial. Of these, 1,327 were non-users of antihistamines (mean age 64.4 years, 64.1% female, mean BMI 29.0 kg/m2) and 158 reported use of antihistamines of any duration during the trial (mean age 64.5 years, 75.2% female, mean BMI 28.1 kg/m2). Seventy-four participants reported use of antihistamines of a duration between 1-49 days, 21 participants between 50-299 days, and 63 reported use of 300 days or more. As illustrated in Figure 1A, the mean JSW change from baseline in the group of non-users was -0.32 mm (95% CI: -0.36 to -0.29), versus -0.19 mm (95%CI: -0.29 to -0.08, p=0.02 for difference) in the group of patients reporting antihistamine use of any duration. A trend towards an association between duration of antihistamine use and reductions in narrowing of JSW was observed (p for trend: 0.02), Figure 1B).

Conclusion

Use of antihistamines was associated with reduced structural progression in knee OA. Further research evaluating the role of antihistamines in OA is needed to further characterize this observation.

Disclosure of Interests

Asger Reinstrup Bihlet Shareholder of: Shareholder of NBCD A/S, Employee of: Employee at NBCD A/S, Claire Prener Miller Employee of: Employee at NBCD A/S, Inger Byrjalsen Employee of: Past employee at NBCD A/S, Jeppe Ragnar Andersen Shareholder of: Shareholder of NBCD A/S, Employee of: Employee at NBCD A/S, Morten Karsdal Shareholder of: Shareholder of Nordic Bioscience A/S, Employee of: Employee at Nordic Bioscience A/S, Matthew C. Baker Shareholder of: Shareholder of Mobility Bio Inc., Employee of: Employee at Mobility Bio Inc., Tharaknath Rao Shareholder of: Shareholder of Mobility Bio Inc., Employee of: Employee of Mobility Bio Inc.

AB0984 CHANGES IN PLASMA VOLUME WHEN MEASURING BIOCHEMICAL MARKERS OF JOINT TISSUE TURNOVER IN RELATION TO ACUTE PHYSICAL ACTIVITY

Background

Physical activity can induce acute changes in plasma volume (PV) and thereby influence concentration of plasma constituents, such as biochemical markers1,2. However, it remains undocumented to what extent PV changes occur during physical exercise in osteoarthritis (OA) patients.

Objectives

Investigating the direct course and magnitude of PV changes during and after weight-bearing (WB) and non-weight-bearing (NWB) exercise, adrenaline-induced cardiovascular stress and resting in an OA population.

Methods

Data originates from the EFEX-OA-02 study (Reg. no.: NCT04542668), which explored biomarker changes in knee OA patients during and after running, cycling, adrenaline infusion and resting on separate days. Blood samples were obtained before, during, at five time points after and again 24 hours post exercise/infusion. Hemoglobin (Hgb) and derived hematocrit (Hct) were measured at all time-points to monitor PV fluctuations.

Main inclusion criteria: Cumulative Kellgren-Lawrence (KL) radiographic grade of the left and right knee of ≥ 2, 40-75 years of age, bodyweight 50-100 kg and BMI 18.5-35.0 kg/m2.

Active interventions consisted of 4x5-minute intervals each progressing from low intensity and peaking at ≥80% of the heart rate reserve (HRR). For the adrenaline infusion, 0.06 mg/kg of adrenalin was prepared in 50 mL saline and administered intravenously. At rest, blood samples were collected at time points similar to the other study interventions, however the 24-hour follow-up sample was omitted.

Hgb was measured on a ABL800 FLEX blood gas analyzer and converted to Hct using the formula: Hct (%) = (0.0485 × ctHb (mmol/L) + 0.0083) × 100. Estimated PV change (% ΔPV) was calculated as: % ΔPV = [100 / (100 – Hctpre)] x [100 (Hctpre – Hctpost) / Hctpost], where: ΔPV % = Percentage change in PV: Hctpre = Hct before exercise, Hctpost = Hct after exercise. A repeated measures linear mixed-model and 1-way ANOVA was used to assess PV changes and compare interventions, respectively.

Results

Forty subjects were included. Mean age was 60.4 years (Standard deviation (SD): 8.7), 16 (40%) were male, mean BMI was 27.0 kg/m2 (SD: 3.5), and mean score in the nine item pain domain of the Knee Injury and Osteoarthritis Outcome Score (KOOS) at baseline was 67.5 (SD: 15.2) out of 100 (0 and 100 corresponding to max pain and no pain, respectively). Baseline Hgb was 9.05 mmol/L (SD: 0.68) and Hct was 44.7% (SD: 2.9%). All subjects were able to reach the defined peak cardiovascular intensity or higher during exercise, while reaching on average 70% (SD: 8.7%) of that during the adrenaline infusion.

Cycling, running and adrenaline infusion led to acute reductions in PV compared to rest: Cycling -14.3% (95%CI: -10.0 to -18.7%), running -13.9% (95%CI: -10.9 to -17.0%), adrenaline -7.8% (95%CI: -4.2 to -11.5%). The reductions in PV induced by both cycling and running were greater compared to adrenaline (p<0.001). There was no difference in PV changes after cycling vs. running (p=0.99). Thirty minutes after both modes of exercise, PV had returned to baseline. After completion of the adrenaline infusion, PV returned to baseline at 30-60 minutes, but was lower than baseline levels at 120 minutes by -3.9% (95%CI: -0.7 to -7.1%), at 240 minutes by -5.3% (95%CI: -2.1 to -8.6%), and at 24-hour by -5.9% (-2.0 to -9.9%). During seated rest, PV initially increased (3.1%, 95%CI: 0.7-5.4%) (Figure 1).

Conclusion

Moderate-high intensity running, cycling and cardiovascular stress led to rapid reductions in PV of knee OA patients. Adjustment for PV changes should be considered when measuring biochemical markers in relation to physical activity.

References

[1]Kaltreider NL, Meneely GR: THE EFFECT OF EXERCISE ON THE VOLUME OF THE BLOOD. J Clin Invest, 1940.

[2]Novosadová J: The changes in hematocrit, hemoglobin, plasma volume and proteins during and after different types of exercise. Eur J Appl Physiol Occup Physiol, 1977.

Disclosure of Interests

Jonathan Bjerre-Bastos: None declared, Casper Sejersen: None declared, Henning Bay Nielsen: None declared, Niels Secher: None declared, Carl-Christian Kitchen: None declared, Claire Prener Miller: None declared, Abigail Mackey: None declared, Asger Reinstrup Bihlet Employee of: Full-time employee of NBCD/Sanos Group A/S

POS1112 A RANDOMIZED, CROSS-OVER STUDY TO INVESTIGATE THE EFFECT OF WEIGHT-BEARING VS NON-WEIGHT-BEARING EXERCISE AND CARDIOVASCULAR STRESS ON TYPE II COLLAGEN TURNOVER IN KNEE OSTEOARTHRITIS PATIENTS – BIOMARKER DATA FROM THE EFEX-OA-02 STUDY

Background

Biomechanical stress is a prerequisite for OA development and studies have shown a difference in the effect of impact- and shear stress2, although studies of the direct impact of exercise on cartilage turnover have not demonstrated clear trends1.

Objectives

Exploring how weight-bearing (WB), non-weight-bearing (NWB) exercise and cardiovascular stress influence circulating biomarkers of cartilage extracellular matrix turnover in OA.

Methods

EFEX-OA-02 was a randomized, cross-over, clinical study investigating the direct effect of exercise on joint biomarkers in knee OA. Subjects were randomized to an order of cycling and running followed by adrenaline infusion and finally resting one week apart. Exercise and infusion sessions were multiphasic, consisting of 4x5-minute intervals. Peak cardiorespiratory stress (PCS) per interval was set to ≥80% of the heart rate reserve during exercise. Blood samples were obtained before, during, at five time points after and 24 h post exercise/infusion. For adrenaline infusion, 0.06 mg/kg of adrenaline was prepared in a 50 mL saline solution and administered intravenously. At rest, samples were collected at corresponding time points, except for the 24 h sample, which was omitted. Levels of serum C2M, T2CM (type II collagen degradation) and PRO-C2 (type II collagen formation) were measured using ELISA-assays (Nordic Bioscience). Coll2-1 and Coll2-1NO2 (type II collagen degradation) were measured using ELISA (Artialis).

Changes in biomarker concentrations after activity were compared to baseline (BL) and the corresponding resting samples. We used ANCOVA and Dunnett’s test with geometric means of change from BL up to 240 min as the dependent variable and subject and activity as covariates. Paired t-test was used to compare values at 24-hour to BL.

Results

Forty subjects were included. Mean age was 60.4 years (SD: 8.7), 24 (60%) were females, mean BMI was 27.0 kg/m2 (SD: 3.5), 18 had cumulated KL grade of 2 or 3 (45%) and 22 (55%) had KL 4, 5 or 6. and mean KOOS pain at BL was 67.5 (SD: 15.2) corresponding to mild-moderate pain. All subjects reached minimum PCS during exercise, but only an average of 70% (SD: 8.7) of that during infusion.

Cycling induced a small reduction in C2M (peak: -5.3%, 95%CI: -7.8 to -2.7%). PRO-C2 increased rapidly in response to cycling (peak: 11.7%, 95%CI: 4.3 to 19.1%) and running (peak: 12.9%, 95%CI: 3.54 to 22.2%). T2CM decreased up to one hour after cycling (peak: -10.8%, 95%CI: -15.1 to -6.5%) and running (peak: -9.5%, 95%CI: -15.5 to -3.6%), similar to adrenaline, then increased. Coll2-1NO2 increased rapidly following cycling (peak: 12.5%, 95%CI: 2.8 to 22.2%) and running (peak: 9.8%, 95%CI: 0.26 to 19.6%). Trends of increase was found in Coll2-1 (21.3%, 95%CI: 2.9 to 39.6) and Coll2-1NO2 (11.6%, 95%CI: -7.9 to 31.1%) in response to running at 240 min (Figure 1 – Error bars: SE, *Change to resting, †Change from BL, */†: P < 0.05, **/††: P < 0.01 ***/†††: P<0.001).

Figure 1.

At 24h PRO-C2 reduced -9.4% (95%CI: -18.2 to -0.5%) after cycling, Coll2-1NO2 reduced -8.33% (95%CI: -17.0 to 0.3%) after running and T2CM elevated by 6.0% (95%CI: -0.8 to 12.8%) after running and 7.1% (95%CI: 0.5 to 13.7%) after cycling.

Conclusion

Running, cycling and adrenaline infusion induced rapid small-to-moderate changes in circulating biomarkers reflecting type II collagen turnover. Changes after adrenaline-infusion suggests a cardiovascular contribution to exercise-induced changes. This model could potentially be used to evaluate treatment effects on collagen turnover.

References

[1]Bjerre-Bastos JJ, Karsdal MA, Boesen M, Bliddal H, Bay-Jensen A, Andersen JR, Bihlet AR: The acute and long-term impact of physical activity on biochemical markers and MRI measures in osteoarthritis—Perspectives for clinical osteoarthritis research. Transl Sport Med, 2020.

[2]Vincent TL: Mechanoflammation in osteoarthritis pathogenesis. Semin Arthritis Rheum, 2019.

Disclosure of Interests

Jonathan Bjerre-Bastos: None declared, Casper Sejersen: None declared, Henning Bay Nielsen: None declared, Mikael Boesen Speakers bureau: Speaker for Novartis and Eli Lilly, Niels Secher: None declared, Gregorio Distajo: None declared, Vincent Flood: None declared, Yves Henrotin Employee of: Founder and President of Artialis SA, Melanie Uebelhoer Employee of: Employee of Artialis, Abigail Mackey: None declared, Peter Krustrup: None declared, Carl-Christian Kitchen: None declared, Ema Petersen: None declared, Christian Thudium Shareholder of: Shareholder Nordic Bioscience A/S, Employee of: Full-time employee at Nordic Bioscience A/S, Jeppe Ragnar Andersen Employee of: Full-time employee of NBCD/Sanos Group A/S, Asger Reinstrup Bihlet Employee of: Full-time employee of NBCD/Sanos Group A/S

POS0180 THE EFFICACY AND SAFETY OF A FIXED-DOSE COMBINATION OF APOCYNIN AND PAEONOL IN SYMPTOMATIC KNEE OA: A DOUBLE-BLIND, RANDOMIZED, PLACEBO-CONTROLLED CLINICAL TRIAL

Background

There is a great unmet need for the development of effective treatments to treat the symptoms of OA. Nuclear-Factor Kappa-B (NF-κB) and Nrf2 play a key roles in OA pathogenesis and have been identified as potential targets. A fixed-dose combination of apocynin and paenol in a ratio of 2:7 (APPA) has been shown to inhibit activation of NF-κB and upregulate Nrf2. [1]

Objectives

We report the results of a phase 2a study evaluating the efficacy and safety of APPA in patients with symptomatic knee OA.

Methods

The trial was a 28-day randomized, placebo-controlled, double-blind study comparing 800 mg of APPA twice daily with matched placebo capsules. Patients with radiographic knee OA KL-grade 2-3, and a WOMAC pain score ≥40 and ≤90/100 of target knee at screening and baseline were randomized 1:1 to APPA or placebo. Main exclusion criteria included recent intraarticular surgery or injection therapy, hip pain greater than the target knee, and BMI ≥40 kg/m2. The primary endpoint was change from baseline to Day 28 in the WOMAC pain score. Safety outcomes included reported adverse events (AE), clinical laboratory parameters, ECG, and vital signs.

A pre-defined subgroup analysis in subjects with a baseline PainDETECT score >12 indicated a positive effect. Accordingly, post-hoc analyses were undertaken to further assess the effects of APPA in subgroups of participants with higher disease severity.

Results

152 participants were randomized, and 149 (98%) completed the trial. The mean (SD) WOMAC pain score at baseline was 55.3 (10.2). The two groups were comparable in terms of baseline pain score, gender, age, and BMI.

The primary endpoint was not met, mean difference (MD) between APPA and placebo was -0.89 (95 % CI: -5.62, 3.84, p=0.71, Figure 1A). Similarly, no significant differences were found on other key secondary endpoints (WOMAC Function and WOMAC total Figure 1B and C, respectively.) APPA was well tolerated and no differences in frequencies of reported AEs were noted, apart from a higher proportion of subjects reporting mild to moderate gastrointestinal discomfort reported with APPA compared to placebo (12% vs. 6.5 %).

In the pre-defined subgroup of participants with baseline PainDETECT ≥ 13 (N=45), the difference in mean change in pain from baseline favored the APPA-group (MD: -11.20, 95 % CI: -20.29 to -2.11, p=0.02). Analysis of participants > 50 WOMAC pain at baseline (Group 1, N=95, Figure 1D), and a KL-grade of the non-target knee >2 (Group 2, N=105, Figure 1E), and a combination of these two criteria (Group 3, N=64, Figure 1F) found a positive effect of APPA compared to placebo (Group 1 MD: -2.61, 95 % CI: -8.98 to 3.76, p=0.42, Group 2 MD: -4.01, 95 % CI: -9.35 to 1.33, p=0.14, and Group 3 MD: -8.32, 95 % CI: -15.48 to -1.16, p=0.02).

Conclusion

Treatment with APPA 800 mg twice daily for 28 days in patients with symptomatic knee OA overall was not associated with significantly improved outcomes compared to placebo. The treatment was well-tolerated and safe. Subgroup analyses, however, showed a significant effect of APPA in patients with moderate to severe OA, indicating that further research in the effects of APPA in appropriate patients is warranted.

References

[1]Cross AL, Hawkes J, Wright HL, Moots RJ, Edwards SW. APPA (apocynin and paeonol) modulates pathological aspects of human neutrophil function, without supressing antimicrobial ability, and inhibits TNFα expression and signalling. Inflammopharmacology. 2020 Oct; 28(5):1223-1235.

Disclosure of Interests

Asger Reinstrup Bihlet Shareholder of: NBCD A/S, Employee of: NBCD A/S, Inger Byrjalsen Employee of: NBCD A/S, Jeppe Ragnar Andersen Shareholder of: NBCD A/S, Employee of: NBCD A/S, Anna Metnik Shareholder of: NBCD A/S, Employee of: NBCD A/S, Alan Reynolds Shareholder of: AKL R&D, Employee of: AKL R&D, Nicholas Larkins Shareholder of: AKL R&D, Employee of: AKL R&D, Peter Alexandersen: None declared, Helene Rovsing: None declared, Ulla Schmidt: None declared, Robert Moots Speakers bureau: Pfizer, Amgen, Novartis, Gilead, Grant/research support from: University of Liverpool received grant support from AKL on Phase 1 trial where Prof. Rob Moots was principal investigator. UoL also received grant support from AKL on basic neutrophil research., Philip G Conaghan Speakers bureau: AbbVie, BMS, Eli Lilly, Galapagos, Gilead, Novartis, Pfizer and UCB, Consultant of: AbbVie, BMS, Eli Lilly, Galapagos, Gilead, Novartis, Pfizer and UCB

Rationale and study design of a randomized, placebo-controlled, double-blind phase 2b trial to evaluate efficacy, safety, and tolerability of an oral glutaminyl cyclase inhibitor varoglutamstat (PQ912) in study participants with MCI and mild AD-VIVIAD

BACKGROUND

Varoglutamstat (formerly PQ912) is a small molecule that inhibits the activity of the glutaminyl cyclase to reduce the level of pyroglutamate-A-beta (pGluAB42). Recent studies confirm that pGluAB42 is a particular amyloid form that is highly synaptotoxic and plays a significant role in the development of AD.

METHODS

This paper describes the design and methodology behind the phase 2b VIVIAD-trial in AD. The aim of this study is to evaluate varoglutamstat in a state-of-the-art designed, placebo-controlled, double-blind, randomized clinical trial for safety and tolerability, efficacy on cognition, and effects on brain activity and AD biomarkers. In addition to its main purpose, the trial will explore potential associations between novel and established biomarkers and their individual and composite relation to disease characteristics.

RESULTS

To be expected early 2023 CONCLUSION: This state of the art phase 2b study will yield important results for the field with respect to trial methodology and for the treatment of AD with a small molecule directed against pyroglutamate-A-beta.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04498650.

Does moderate intensity impact exercise and non-impact exercise induce acute changes in collagen biochemical markers related to osteoarthritis? - An exploratory randomized cross-over trial

OBJECTIVE

To investigate acute changes in biochemical markers of cartilage turnover in response to moderate intensity exercise with and without joint impact in humans with knee osteoarthritis.

DESIGN

We conducted a randomized, cross-over, exploratory clinical study. Twenty subjects with knee osteoarthritis (OA) were randomized, of which twenty completed 30 min of cycling and 15 completed 30 min of running on days 1 week apart. Fasting blood samples were taken before, immediately after and 1, 2, 3, and 24 h after activity was initiated. Midstream spot urine was sampled before and after activity. Serum samples were analyzed for concentrations of fragment of type II collagen degradation, C2M, fragment of type VI collagen degradation, C6M, cartilage oligomeric matrix protein, COMP, marker of type II collagen formation, PRO-C2, and urine for marker of crosslinked type II collagen degradation, CTX-II. To establish a reference, all subjects had similar samples taken during rest on a separate day. Data was analyzed in a restricted maximum likelihood based random effects linear mixed model.

RESULTS

C2M trended to increase after cycling compared running (13.49%, 95%CI: -0.36-27.34%) and resting (12.88%, 95%CI: 0.2-25.6%) and the type II collagen formation/degradation ratio switched towards degradation after cycling, but not running. C6M trended to decrease after cycling (-8.1%, 95%CI: -14.8 to -1.4%) and running (-6.8%, 95%CI: -14.16-0.55%).

CONCLUSION

In persons with knee OA moderate intensity exercise without joint impact may induce acute changes in circulating levels of biochemical markers reflecting type II and VI collagen degradation.

FRI0404 SEPERATION OF HIGH AND LOW RESPONSE GROUPS IN OSTEOARTHRITIS USING SERUM CARTILAGE DEGRADATION AND FORMATION MARKERS – A 3 YEAR FOLLOW-UP ON THE FORWARD STUDY TESTING THE EFFICACY OF SPRIFERMIN

Background:

In osteoarthritis (OA), response to different interventions could be more pronounced in different endotypes of cartilage turnover. Data from UK biobank suggest that an endotype of low cartilage repair is associated with structural progression in osteoarthritis (OA)[1]. Sprifermin a truncated and recombinant FGF18 have been shown to induce chondrocyte proliferation and cartilage formation in in vitro settings[2–4]. Efficacy on cartilage thickness in OA was recently demonstrated in the FORWARD study[5].

Objectives:

We investigated markers of cartilage formation (serum PRO-C2) and degradation (urine CTX-II), to assess profiles indicative of chondrocyte metabolic activity would be associated with both structural and symptomatic responses to sprifermin.

Methods:

Serum and urine from participants of the FORWARD study, a phase II clinical trial testing the efficacy of intra-articular (IA) sprifermin, were collected throughout the study. Clinical data recorded at baseline, year 2 and year 3 follow-up were used, including cartilage thickness and WOMAC. All available baseline samples of the placebo and treatment arms were assessed for serum PRO-C2 and urinary CTX-II. Patients were separated into dichotomized groups based on 33, 50 or 66 percentiles cut-points and two-year treatment responses were compared in a prospective-retrospective statistical design manner.

Results:

Patients with low baseline PRO-C2 (<66%), in the 100ug/4x treatment arm, had greater difference to placebo in cartilage thickness as compared to the high PRO-C2 and all-comers groups (0.06 vs 0.03 and 0.05 mm, respectively) at two and three years (Fig.). Similar effect was seen for low CTX-II (<50%) (0.07 vs -0.03 and 0.05 mm, respectively). In addition, the WOMAC placebo effect was reduced in the low PRO-C2 and the low CTX-II groups, resulting in a difference compared to placebo of -0.81vs. 1.35 (low vs high proC2 and -2.35 vs 1.47 (low vs high CTX-II).

Conclusion:

We noticed that low baseline PRO-C2 and CTX-II indicative for low metabolic activity of chondrocytes were associated with improved symptomatic outcome and slightly increased cartilage thickness compared to high metabolic activity. The parallelism between PRO-C2 and CTX-II point towards the existence of a low cartilage repair endotype and might reflect a subgroup of patients with higher sensitivity towards interventions - an effect that was maintained over three years.

References:

[1]Tachmazidou I, et al. ”Identification of new therapeutic targets for osteoarthritis through genome-wide analyses of UK Biobank data.” Nat Genet 2019;51:230–6.

[2]Gigout A, et al. ”Sprifermin (rhFGF18) enables proliferation of chondrocytes producing a hyaline cartilage matrix”. Osteoarthr Cartil. 2017;25.

[3]Reker D et al. “Sprifermin (rhFGF18) modulates extracellular matrix turnover in cartilage explants ex vivo”. J Transl Med. 2017;15.

[4]Luo Y et al. ”A Novel High Sensitivity Type II Collagen Blood-Based Biomarker, PRO-C2, for Assessment of Cartilage Formation”. Int J Mol Sci 2018;19:3485.

[5]Hochberg MC et al. “Effect of Intra-Articular Sprifermin vs Placebo on Femorotibial Joint Cartilage Thickness in Patients With Osteoarthritis”. JAMA. 2019; Oct 8;322(14).

Disclosure of Interests:

Hans Gühring Employee of: Merck KGaA, Anne-Christine Bay-Jensen Shareholder of: Nordic Bioscience A/S, Employee of: Full time employee at Nordic Bioscience A/S., Flavie Moreau Employee of: Merck KGaA, Jeppe Ragnar Andersen Shareholder of: Nordic Bioscience A/S., Employee of: Full time employee of Nordic Bioscience., Asger Reinstrup Bihlet Shareholder of: Nordic Bioscience A/S., Morten Karsdal Shareholder of: Nordic Bioscience A/S., Employee of: Full time employee at Nordic Bioscience A/S.

AB0360 EFFICACY AND SAFETY OF THE PROSTAGLANDIN EP4 RECEPTOR ANTAGONIST CR6086 ADDED TO METHOTREXATE IN DMARD-NAÏVE EARLY RA PATIENTS: A PHASE 2 RANDOMIZED CONTROLLED TRIAL

Background:

MTX is the first line treatment in early RA. There is robust evidence from cohort studies, but less from RCTs, that a “window of opportunity” exists over 12-16 weeks symptom duration. CR6086 is a selective prostaglandin EP4 receptor antagonist, with an immunomodulatory profile.

Objectives:

To test efficacy and safety of CR6086 added to MTX in early RA, DMARD-naïve patients.

Methods:

Patients with RA (ACR/EULAR 2010 criteria), < 1 year from symptom onset and naïve to DMARDs were randomized to oral CR6086 30, 90, 180mg, or placebo bid and oral MTX (20mg weekly) for 13 weeks (NCT03163966). Primary endpoint was the ACR20 response rate: 240 patients were needed to detect a difference among groups, with 50% responders on placebo and 70% on the 90mg CR6086 target dose. Pairwise comparisons of proportions were performed, with nonresponder imputation for withdrawals. A subgroup of patients underwent dynamic contrast-enhanced (DCE) MRI for quantification of synovitis at MCP and wrist joints, evaluated as DEMRIQ-ME and DEMRIQ-vol.

Results:

The ITT population included all 244 randomized patients receiving at least one dose of study drugs (59 CR6086 30mg/MTX, 60 CR6086 90mg/MTX, 63 CR6086 180mg/MTX, 62 placebo/MTX). Safety was good with no increased rate of infections or other disorders; however, there were more minor upper GI adverse events (AEs) with CR6086, and increased dropouts due to AEs with the 180mg dose (9/63, 14.3% vs 1.7-3.4% in other groups). There were more ACR20 responders with MTX monotherapy than predicted (59.7%) and thus the 10.3% difference with the 90mg target dose (70.0%) was not significant. The low 30mg dose was no better than placebo (55.9%), while the high 180mg dose did not provide additional benefit compared with 90mg (74.0% net of dropouts). CR6086 90mg and 180mg induced a significant improvement in MRI, compared with placebo (Fig. 1). In a post-hoc analysis in patients < 6 months from symptom onset (ACR definition of early RA: 98/244, 40.2%), MTX monotherapy exerted a large 76% ACR20 response rate that precluded potentiation. Conversely, in patients of 6-12 months disease duration (146/244, 59.8%) ACR20 responders were 48.6% with MTX monotherapy vs 68.4% with 90mg, i.e. a 19.8% difference as postulated, with proportional differences in secondary endpoints (Tab. 1).

Conclusion:

There was no benefit demonstrated for CR6086 added to MTX in the study cohort as a whole. However, in a post-hoc analysis, enhanced responses were observed with CR6086 90mg bid added to MTX in patients >6 months disease duration. This generated the hypothesis that addition of CR6086 90mg bid may benefit in RA patients initiating MTX after the window of opportunity, to be tested in further studies.

Table 1.

Patient characteristics & pregnancy outcomes

Symptom onset <12 months(principal analysis)Symptom onset 6-12 months(post-hoc analysis)*Placebo+MTX(N=62)CR6086 90mg+MTX(N=60)Placebo+MTX(N=37)CR6086 90mg+MTX(N=38)ACR20, %59.7%70.0%48.6%68.4%ACR50, %33.9%38.3%29.7%39.5%ACR70, %17.7%23.3%10.8%28.9%DAS28 (CRP) <2.6, %12.9%20.0%8.1%18.4%CDAI ≤2.8, %8.1%11.7%5.4%15.8%SDAI ≤3.3, %6.5%10.0%2.7%15.8%Boolean-based remission, %6.5%6.7%2.7%10.5%

*In patients with symptom onset <6 months, MTX monotherapy exerted a large 76% ACR20 response, and correspondingly high secondary efficacy parameters, precluding potentiation in this subset

Figure 1.

Change in MRI (DEMRIQ-ME#) after 13 weeks

Disclosure of Interests:

Karel Pavelka Consultant of: Abbvie, MSD, BMS, Egis, Roche, UCB, Medac, Pfizer, Biogen, Speakers bureau: Abbvie, MSD, BMS, Egis, Roche, UCB, Medac, Pfizer, Biogen, Ivanova Delina2 Delina: None declared, Minodora Mazur: None declared, Massimo D’Amato Employee of: Rottapharm Biotech, GIAMPAOLO GIACOVELLI Employee of: Rottapharm Biotech, Federica Girolami Employee of: Rottapharm Biotech, Marek Krogulec: None declared, René Østgård: None declared, Asger Reinstrup Bihlet Shareholder of: Nordic Bioscience A/S., Olga Kubassova Shareholder of: IAG, Image Analysis Group, Consultant of: Novartis, Takeda, Lilly, Employee of: IAG, Image Analysis Group, Lucio Rovati Shareholder of: Rottapharm Biotech, Employee of: Rottapharm Biotech, Peter C. Taylor Grant/research support from: Celgene, Eli Lilly and Company, Galapagos, and Gilead, Consultant of: AbbVie, Biogen, Eli Lilly and Company, Fresenius, Galapagos, Gilead, GlaxoSmithKline, Janssen, Nordic Pharma, Pfizer Roche, and UCB

OP0189 ASSESSMENT OF CARTILAGE DEGRADATION AND PROTECTIVE MARKERS IN SYNOVIAL FLUID FROM OSTEOARTHRITIS PATIENTS BEFORE AND AFTER CYCLES OF INTRA-ARTICULAR INJECTIONS WITH SPRIFERMIN

Background:

It is challenging to monitor treatment effects after intra-articular (IA) injection with tissue modifying drugs. Assessment of biomarker levels in synovial fluid may be one solution to the challenge. Sprifermin is a truncated form of fibroblast growth factor (FGF) 18 known to induce chondrocyte proliferation and type II collagen formation [1,2]. Data from preclinical investigations show that cartilage formation happens in different phases after therapy with sprifermin, starting with a phase of cartilage degradation during the induction of proliferation of chondrocytes followed by a phase of cartilage formation/production of extracellular matrix.

Objectives:

The aim was to investigate the effect of IA administrated sprifermin on cartilage turnover activity as compared to placebo in the injected joint by measurement of markers using longitudinal synovial fluid samples of patients participating in the FORWARD study.

Methods:

Each included patient had baseline and at least one FU sample available. Synovial fluid (SF) from participants receiving injections at three consecutive weeks in six month intervals through to week (wk) 80 (fig.A) available from the phase II clinical trial evaluating the efficacy and safety of intraarticularly delivered sprifermin [3] were selected for the investigations. Biochemical markers were measured in available SF samples of the placebo (containing saline IA, n=38) and the highest sprifermin dose group (100 mcg/IAx4, n=59). Samples were pretreated with ultrasound and centrifugation to decrease viscosity. Markers measured were PRO-C2 (type II collagen formation), huARGS (aggrecan degradation), and FBN-C (fibronectin). Markers are technically validated for synovial fluid measurement. Data were individually normalized to baseline to investigate the median proportional change over time.

Results:

Baseline mean (SD) levels of the markers in SF at BL were: PRO-C2, 21.4 (13.6) ng/mL, huARGS, 1117 (516) pM and FBN-C, 2556 (1959) ng/mL. PRO-C2 was initially decreased (from BL to wk 2) after injection with sprifermin; however, the level was increased at the beginning of each new injection cycle followed by a decrease after injection of sprifermin (Fig.B). Overall synovial PRO-C2 levels increased over time in therapy with sprifermin, while no change was observed for the placebo arm. huARGS showed a similar pattern as PRO-C2 – there was an overall increase in ARGS over time in the sprifermin group (fig.C). Interestingly ARGS continuously decreased over time in the placebo group. FBN-C is continuously increased after injection’s cycles, whereas no effect was seen in the placebo group (fig.D).

Conclusion:

Confirmatory of the preclinical investigations a biphasic response on cartilage turnover after injection with sprifermin was observed. Biochemical indications of cartilage formation and chondrocyte proliferation was only modulated in the sprifermin group, and cartilage degradation (ARGS) was temporal induced and reduced by sprifermin and placebo injections, respectively.

References:

[1]Gigout A, et al. “Sprifermin (rhFGF18) enables proliferation of chondrocytes producing a hyaline cartilage matrix”. Osteoarthr Cartil. 2017;25.

[2]Reker D, et al. “Sprifermin (rhFGF18) modulates extracellular matrix turnover in cartilage explants ex vivo”. J Transl Med. 2017;15.

[3]Hochberg MC, et al. “Effect of Intra-Articular Sprifermin vs Placebo on Femorotibial Joint Cartilage Thickness in Patients With Osteoarthritis”. JAMA. 2019; Oct 8;322(14).

Disclosure of Interests:

Anne-Christine Bay-Jensen Shareholder of: Nordic Bioscience A/S, Employee of: Full time employee at Nordic Bioscience A/S., Angela Manginelli Employee of: Merck KGaA, Flavie Moreau Employee of: Merck KGaA, Yi He Employee of: YH is a full time employee of Nordic Bioscience A/S, Yunyun Luo Employee of: Nordic Bioscience A/S, Jeppe Ragnar Andersen Shareholder of: Nordic Bioscience A/S., Employee of: Full time employee of Nordic Bioscience., Asger Reinstrup Bihlet Shareholder of: Nordic Bioscience A/S., Morten Karsdal Shareholder of: Nordic Bioscience A/S., Employee of: Full time employee at Nordic Bioscience A/S., Hans Gühring Employee of: Merck KGaA, Christoph Ladel Employee of: Merck KGaA

Disease-modifying treatments for osteoarthritis (DMOADs) of the knee and hip: lessons learned from failures and opportunities for the future

Osteoarthritis (OA) is the biggest unmet medical need among the many musculoskeletal conditions and the most common form of arthritis. It is a major cause of disability and impaired quality of life in the elderly. We review several ambitious but failed attempts to develop joint structure-modifying treatments for OA. Insights gleaned from these attempts suggest that these failures arose from unrealistic hypotheses, sub-optimal selection of patient populations or drug dose, and/or inadequate sensitivity of the trial endpoints. The long list of failures has prompted a paradigm shift in OA drug development with redirection of attention to: (1) consideration of the benefits of localized vs systemic pharmacological agents, as indicated by the increasing number of intra-articularly administered compounds entering clinical development; (2) recognition of OA as a complex disease with multiple phenotypes, that may each require somewhat different approaches for optimizing treatment; and (3) trial enhancements based on guidance regarding biomarkers provided by regulatory agencies, such as the Food and Drug Administration (FDA), that could be harnessed to help turn failures into successes.