The efficacy and safety of a fixed-dose combination of apocynin and paeonol, APPA, in symptomatic knee OA: A double-blind, randomized, placebo-controlled, clinical trial.

OBJECTIVE: Apocynin (AP) and paeonol (PA) are low molecular weight phenolic compounds with a broad array of anti-inflammatory and immunoregulatory effects. This study assessed of a fixed-dose combination of APPA in people with symptomatic knee osteoarthritis (OA). METHODS: A multi-center, randomized, placebo-controlled, double-blind phase 2a trial enrolled participants with radiographic knee OA (Kellgren-Lawrence, KL, grades 2-3) and pain ≥40/100 on WOMAC pain subscale, and evaluated the efficacy and safety of oral APPA over a 28-day period. APPA 800 mg or matching placebo was administered twice daily in a 1:1 ratio. Post-hoc analyses explored the response to APPA in sub-groups with more severe pain and structural severity. RESULTS: The two groups were comparable at baseline; 152 subjects were enrolled and 148 completed the trial. There was no statistically significant difference between groups with respect to the primary outcome, WOMAC pain (mean difference between groups was -0.89, 95% CI: -5.62, 3.84, p = 0.71), nor WOMAC function or WOMAC total. However, predefined subgroup analyses of subjects with symptoms compatible with neuroplastic/neuropathic pain features showed a statistically significant effect of APPA compared to placebo. Adverse events (mainly gastrointestinal) were mild to moderate. CONCLUSION: Treatment with APPA 800 mg twice daily for 28 days in subjects with symptomatic knee OA was not associated with significant symptom improvement compared to placebo. The treatment was well-tolerated and safe. While the study was not powered for such analysis, pre-planned subgroup analyses showed a significant effect of APPA in subjects with neuroplastic pain/severe OA, indicating that further research in the effects of APPA in appropriate patients is warranted.

Safety, Tolerability, and Pharmacodynamics of the ADAMTS-5 Nanobody M6495: Two Phase 1, Single-Center, Double-Blind, Randomized, Placebo-Controlled Studies in Healthy Subjects and Patients With Osteoarthritis.

OBJECTIVE: To assess the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of single and multiple injections of M6495, a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS-5)  nanobody, in healthy volunteers and patients with osteoarthritis. METHODS: Two randomized, placebo-controlled, double-blind studies were performed. Study 1 enrolled 54 healthy male volunteers who received one subcutaneous (s.c.) injection of M6495 (1-300 mg) or placebo (ratio 2:1), evaluating safety, PK, and PD as changes in the serum aggrecan fragment alanine-arginine-glycine-serine (ARGS). Study 2 enrolled 32 patients with osteoarthritis with Kellgren-Lawrence grades 2 to 4 and pain greater than or equal to 40 on the Western Ontario and McMaster Universities Arthritis Index pain subscale at screening and evaluated the safety, PK, and PD of three doses every two weeks (75-300 mg per dose) or six once-weekly M6495 s.c. doses (300 mg) or placebo (ratio 3:1) over 106 days' follow-up. RESULTS: M6495 in single and multiple doses of less than or equal to 300 mg s.c. weekly was well tolerated with no clinically significant changes in any safety parameter. Adverse events more frequently reported in the M6495 groups were mostly mild cases of injection site reactions, myalgia, and nausea, which resolved after treatment cessation. The elimination half-life of single s.c. doses of M6495 ranged from 79 to 267 hours. M6495 administration substantially reduced serum ARGS levels, indicative of target engagement and indicating disease-modifying potential of M6495. CONCLUSION: Treatment with M6495 in single and multiple doses up to and including 300 mg s.c. was found to be well tolerated and adequately safe for further clinical evaluation of potential disease-modifying effects.

Joint biomarker response to mechanical stimuli in osteoarthritis - A scoping review.

Objective: Arthritic cartilage is primed for mechanical damage. Joint biochemical markers (JBM) could provide insight into the impact of mechanical stimulation on joint tissue turnover in osteoarthritis (OA) of potential use in clinical OA research and practice. However, existing studies of the acute impact of physical activities (PA) on JBM often contain risks of substantial bias. The purpose of this scoping review was to critically review and discuss existing reports of acute joint tissue turnover as reflected in JBM in relation to PA in OA and propose considerations for future research. Design: We searched PubMed, Embase, and Scopus and reference lists for original reports on the acute impact of PA on JBM in human OA. Identified studies were reviewed by two reviewers forming the basis for the discussion of methodology. Results: Search in databases resulted in nine eligible papers after full-text evaluation. Two additional papers were identified through reference lists, resulting in 11 papers included in this review. Ten investigated knee OA and one investigated hand OA. Biomarkers described were related to turnover of type II collagen, aggrecan, and cartilage oligomeric matrix protein. Conclusions: The literature is dominated by small, simplistic studies, but suggests that mechanical stimulation can induce acute changes in joint biomarkers. In order to diminish the existing bias in future studies, it is important to recognize methodological considerations e.g. patient and biomarker selection as well as peri-interventional control. Common potential sources of bias include the acute shift in plasma volume due to cardiovascular stress and postural changes.

Impact of monitoring approaches on data quality in clinical trials.

AIMS: Source data verification (SDV) has been reported to account for up to 25% of the budget in clinical trials (CT) and cost-benefit of SDV has been questioned. Guidelines for risk-based monitoring (RBM) were published in 2013 by agencies and in 2016, ICH-GCP-E6-(R2) added a requirement for risk-based approaches. This report will perform a comparison of the impact of RBM vs classic monitoring (CM) on data quality (defined as accuracy of data reporting from source data to final trial data) and expected impact on costs of CTs. METHODS: Data on residual errors from four, large comparable randomised CTs were examined by post-trial SDV. Observed discrepancies were analysed in the categories of "overall" data, "major efficacy" and "major safety". In each category, the residual error rate was calculated as the number of discrepancies divided by the number of data-fields verified. RESULTS: A total of 1 716 087 data points were verified using CM and 323 174 using RBM. The overall error rate was 0.40% for RBM and 0.37% for CM (P < 0.01). For major efficacy, defined by risk assessment, the error rate was 0.15% and 0.28% (P < 0.0001); in major safety, defined by risk assessment, the error rate was 0.49% and 0.67% (P = 0.15), both in favour of the RBM approach. CONCLUSION: These empirical data, directly comparing RBM with CM, suggest that RBM improves data quality regarding data-points of major importance to trial outcomes, efficacy and major safety. Overall, the RBM approach showed a correlation to reduced amount of data collection errors with major relevance for interpretation of study results and subject safety as well as reducing on-site monitoring and data cleaning resources.

Associations between single-question Visual Analogue Scale pain score and weight-bearing and non-weight-bearing domains of Western Ontario and McMaster Universities Arthritis Index pain: data from 2 phase 3 clinical trials.

Introduction: Visual Analogue Scale (VAS) and the pain subscale of the Western Ontario and McMaster Universities Arthritis Index (WOMAC) are commonly used measuring tools of osteoarthritis (OA) pain. Objectives: The objective of this cross-sectional study was to explore the associations between single-question VAS pain and the weight-bearing and non-weight-bearing domains of WOMAC pain. Methods: Data from 2093 patients with OA participating in 2 phase 3 clinical trials were included for post hoc analyses. Univariate Pearson correlations and comparison of r values were made using z statistics obtained using the Fisher r to z test for all items of the VAS pain scale, the WOMAC pain subscale, the weight-bearing and non-weight-bearing constructs of WOMAC pain subscale, and by subgroups of WOMAC pain quintiles and Kellgren-Lawrence grades. Results: The correlations between VAS pain and WOMAC pain were significant (r = 0.67, P < 0.001) with a slope of 0.57 (95% confidence interval [CI]: 0.54-0.61). A similar correlation was found for weight-bearing pain (r = 0.68, P < 0.001, slope: 0.62 (95% CI: 0.59-0.65) but significantly lower for non-weight-bearing pain (r = 0.55, P < 0.001, slope: 0.49 (95% CI: 0.46-0.52). The degree of disagreement between the 2 instruments seemed to be lesser in the extreme ends of the scales, and the observed association between Kellgren-Lawrence grade and disagreement between VAS and WOMAC was driven by non-weight-bearing pain. Conclusion: In conclusion, VAS pain and WOMAC pain subscale correlation was found to be moderate and the VAS pain scale correlated more accurately with the WOMAC pain weight-bearing questions. This constitutes novel insight into patient with OA pain reporting.

An Estimate of Plasma Volume Changes Following Moderate-High Intensity Running and Cycling Exercise and Adrenaline Infusion.

Introduction: Plasma volume (PV) changes in response to physical activity, possibly as a consequence of adrenergic activation. We estimated changes in PV in response to common exercise modalities; cycling and running as well as adrenaline infusion and control at rest. Methods: On separate days, forty circulatory healthy subjects [aged 60 years (range: 42-75)] with knee osteoarthritis underwent moderate-high intensity cycling, running, and intravenous adrenaline infusion to mimic the circulatory response to exercise. Blood samples were obtained from peripheral veins taken at several pre-defined time points before, during, and after the interventions. PV changes were estimated using venous hemoglobin and the derived hematocrit. The temporal associations between PV and selected biomarkers were explored. Results: Changes in PV were observed during all four interventions, and the response to cycling and running was similar. Compared to rest, PV decreased by -14.3% (95% CI: -10.0 to -18.7) after cycling, -13.9% (95% CI: -10.9 to -17.0) after running, and -7.8% (95% CI: -4.2 to -11.5) after adrenaline infusion. Conclusion: PV decreased in response to moderate-high intensity running and cycling. Adrenaline infusion mimicked the PV change observed during exercise, suggesting a separate influence of autonomic control on blood volume homeostasis. In perspective, a temporal association between PV and biomarker dynamics suggests that consideration of PV changes could be relevant when reporting plasma/serum constituents measured during exercise, but more research is needed to confirm this.

Effect of adrenaline on serum mid-regional pro-atrial natriuretic peptide and central blood volume.

NEW FINDINGS: What is the central question in this study? Atrial natriuretic peptide (ANP) is secreted in response to atrial wall distension and thus allows for evaluation, albeit indirect, of the central blood volume. Adrenaline has chronotropic and inotropic effects. We evaluated whether the chronotropic and inotropic effects of adrenaline were reflected in mid-regional proANP. What is the main finding and its importance? Central blood volume remained stable with infusion of adrenaline and yet mid-regional proANP increased. Thus, the chronotropic and inotropic state of the heart or adrenaline directly induces release of ANP variants from the myocytes. ABSTRACT: Atrial natriuretic peptide (ANP) has vasodilatory, natriuretic and diuretic properties. It is secreted in response to atrial wall distension and thereby provides an indirect evaluation of central blood volume (CBV). Adrenaline has chronotropic and inotropic effects that increase cardiac output. In the present study, we evaluated whether these effects were influenced by an increase in CBV and reflected in mid-regional proANP (MR-proANP) concentrations in the circulation, a stable proxy marker of bioactive ANP. Changes in CBV were evaluated by thoracic electrical admittance and haemodynamic variables monitored by pulse-contour analysis during two intervals with graded infusion of adrenaline. Adrenaline infusion increased heart rate (by 33 ± 18%) and stroke volume (by 6 ± 13%), hence cardiac output (by 42 ± 23%; all P < 0.05). The increase in cardiac output did not result from an increase in CBV, because thoracic electrical admittance remained stable (-3 ± 17%; P = 0.230). Serum MR-proANP concentrations were increased (by 26 ± 25%; P < 0.001) by adrenaline infusion and remained elevated 60 min postinfusion. We conclude that MR-proANP in the circulation is affected not only by CBV, but also by increased chronotropy/inotropy of the heart, or that adrenaline directly induces release of ANP variants from the myocytes.

Symptomatic and structural benefit of cathepsin K inhibition by MIV-711 in a subgroup with unilateral pain: post-hoc analysis of a randomised phase 2a clinical trial.

OBJECTIVES: Osteoarthritis (OA) development programmes face challenges due to discordance between structural changes and symptoms. A novel cathepsin-K inhibitor, MIV-711, recently reported structural benefits, but did not demonstrate a significant difference from placebo in symptoms. Previous work suggests that pain from non-target joints may confound OA pain outcomes. We therefore conducted an exploratory analysis in participants with predominantly unilateral knee pain from the MIV-711-201 trial. METHOSD: Participants scoring below median contralateral knee NRS pain at baseline from the MIV-711-201 phase 2a clinical trial (n=119) were analysed by treatment group for differences in change from baseline in WOMAC pain, quantitative magnetic resonance imaging bone area and cartilage thickness with a repeated-measures mixed model adjusting for relevant co-variates. RESULTS: In the subgroup with unilateral knee pain, treatment with MIV-711 100 mg led to greater reduction in WOMAC pain compared to placebo (-5.0, 95% CI: -8.69 to -1.3, p=0.008), while 200 mg did not (-2.5, 95% CI: -6.5 to 1.6, p=0.23). MIV-711 treatment was associated with a reduced change in bone area compared to placebo (200 mg; -19.6 mm2 , 95% CI: -36.2 to -3.0, p=0.02, and 100 mg; -12.5 mm2 , 95% CI: -27.8 to 2.8, p=0.11,). No observed differences between treatment groups in cartilage thickness were found in this subgroup. CONCLUSIONS: In a subgroup with predominantly unilateral knee pain, significant reduction in OA pain by MIV-711 100 mg treatment was found, with concurrent beneficial structural effects, highlighting the importance of appropriate pain inclusion criteria in OA trials.

The Efficacy and Safety of Multiple Dose Regimens of Kudzu (Pueraria lobata) Root Extract on Bone and Cartilage Turnover and Menopausal Symptoms.

Background: Menopause is associated with detrimental changes in turnover of bone and cartilage and a variety of symptoms with negative impact on the quality of life. Naturally occurring isoflavones from Radix Pueraria lobata, Kudzu root, may possess chondroprotective and symptom-relieving properties, but efficacy and safety of dosing and dose frequencies required for pharmacological action is unclear. Purpose: This clinical trial evaluates the efficacy on bone and cartilage turnover, menopausal symptoms, and safety of five dose regimens of Kudzu root extract administered either once, twice or three times daily in women with at least mild menopausal symptoms. Materials and Methods: Fifty postmenopausal women were randomized equally into five different dose regimen groups of Kudzu root extract in a four-week, parallel group, open-label, single-center, exploratory study design. Biomarkers CTX-I and CTX-II reflecting bone and cartilage degradation, respectively, were assessed in blood samples and 24-h urine samples. Change from baseline in the Menopause Rating Scale (MRS) and subscales was evaluated. Safety endpoints were frequency of adverse events, changes in hematology and safety chemistry data, vital signs and electrocardiogram. Results: Fifty women (Age 54.2 years, SD: 2.9) were randomized. After 4 weeks of treatment, biomarkers of bone resorption and cartilage degradation were statistically significantly reduced from baseline levels in the group receiving two capsules three times a day, serum/urine CTX-I (-18.4%, 95% CI: -8.1 to -27.5, p = 0.001/-34.2%, 95% CI: -21.6 to -44.7, p < 0.0001), urine CTX-II (-17.4% 95% CI: -2.5 to -30.0, p = 0.02). The observed effects were consistent across study groups but appeared to favour three times daily dosing. Four weeks of treatment led to statistically significant reductions in the MRS Total Score (p < 0.0001-0.03) in four out of five treatment groups. Kudzu root extract was well tolerated in all dose regimens, and no serious adverse events were reported. Conclusion: The results indicate that Kudzu extract may possess beneficial effects on bone and cartilage health and may be a promising natural alternative to existing treatments for menopausal symptoms. Kudzu root extract was well tolerated for short-term treatment of mild to severe menopausal symptoms in women in all tested doses and dose frequencies.

A biomarker perspective on the acute effect of exercise with and without impact on joint tissue turnover: an exploratory randomized cross-over study.

PURPOSE: To investigate acute changes in biochemical markers of bone and cartilage turnover in response to moderate intensity exercise with and without joint impact in healthy human subjects. METHODS: A randomized, cross-over, exploratory, clinical study was conducted. Twenty healthy subjects with no history of joint trauma completed 30 min interventions of standardized moderate intensity cycling and running as well as a resting intervention 1 week apart. Blood samples were taken immediately before, four times after exercise and again the next day. Urine was sampled, before, after and the next day. On the day of rest, samples were taken at timepoints similar to the days of exercise. Markers of type I (CTX-I), II (C2M, CTX-II) and VI (C6M) collagen degradation, cartilage oligomeric matrix protein (COMP) and procollagen C-2 (PRO-C2) was measured. TRIAL REGISTRATION NUMBER: NCT04542655, 02 September 2020, retrospectively registered. RESULTS: CTX-I was different from cycling (4.2%, 95%CI: 0.4-8.0%, p = 0.03) and resting (6.8%, 95%CI: 2.9-10.7%, p = 0.001) after running and the mean change in COMP was different from cycling (10.3%, 95%CI: 1.1-19.5%, p = 0.03), but not from resting (8.6%, 95%CI: - 0.7-17.8%, p = 0.07) after running. Overall, changes in other biomarkers were not different between interventions. CONCLUSION: In this exploratory study, running, but not cycling, at a moderate intensity and duration induced acute changes in biomarkers of bone and cartilage extra-cellular matrix turnover.

Long-term structural and symptomatic effects of intra-articular sprifermin in patients with knee osteoarthritis: 5-year results from the FORWARD study.

OBJECTIVE: The FORWARD (FGF-18 Osteoarthritis Randomized Trial with Administration of Repeated Doses) trial assessed efficacy and safety of the potential disease-modifying osteoarthritis drug (DMOAD) sprifermin in patients with knee osteoarthritis. Here, we report 5-year efficacy and safety results. METHODS: Patients were randomised to intra-articular sprifermin 100 µg or 30 µg every 6 months (q6mo) or 12 months, or placebo, for 18 months. The primary analysis was at year 2, with follow-up at years 3, 4 and 5. Additional post hoc exploratory analyses were conducted in patients with baseline minimum radiographic joint space width 1.5-3.5 mm and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain 40-90, a subgroup at risk (SAR) of progression. RESULTS: 378 (69%) patients completed the 5-year follow-up. A significant dose-response in total femorotibial joint cartilage thickness with sprifermin (trend test, p<0.001) and a 0.05 mm mean difference with sprifermin 100 µg q6mo versus placebo (95% CI 0.00 to 0.10; p=0.015) were sustained to year 5. WOMAC pain scores improved ~50% from baseline in all groups. No patient in the 100 µg q6mo group had replacement of the treated knee. 96%-98% of patients receiving sprifermin and 98% placebo reported adverse events, most were mild or moderate and deemed unrelated to treatment. Adverse event-related study withdrawals were <10%. Differentiation in WOMAC pain between sprifermin 100 µg q6mo and placebo in the SAR (n=161) at year 3 was maintained to year 5 (-10.08; 95% CI -25.68 to 5.53). CONCLUSION: In the longest DMOAD trial reported to date, sprifermin maintained long-term structural modification of articular cartilage over 3.5 years post-treatment. Potential translation to clinical benefit was observed in the SAR. TRIAL REGISTRATION NUMBER: NCT01919164.

Safety, tolerability and pharmacokinetic characterisation of DACRA KBP-042 in healthy male subjects.

There is a need for antidiabetic agents successfully targeting insulin sensitivity and treating obesity control at the same time. The aim of this first-in-human study was (a) to evaluate safety and tolerability, (b) to evaluate pharmacokinetics and (c) to assess indications of receptor engagement of single ascending doses of KBP-042, a dual amylin and calcitonin receptor agonist (DACRA) that has shown promising preclinical data, with superior activity in terms of typical amylin-induced responses including reduction of food intake, weight loss and gluco-regulatory capacities. A randomised double-blind placebo-controlled single ascending dose study was performed with six dose levels of KBP-042 (5, 7.5, 10, 20, 20 (evening), 40 ug) in healthy male adults. KBP-042 or placebo was administered as a single dose after an overnight fast, followed by a standardized lunch after 4 hours. KBP-042 was associated with dose-dependent complaints of nausea and vomiting, with a lack of tolerability at doses of 20 µg and above. Doses of 5-40 µg KBP-042 behaved according to a linear pharmacokinetic profile. Indications of target receptor engagement were observed at the level of glucose control and lowering of bone resorption, compared to placebo. The results of this study showed that doses up to 40 µg were safe, although tolerability was not present at the highest doses. The study confirmed target receptor engagement at the studied doses.

Serum C-reactive protein metabolite (CRPM) is associated with incidence of contralateral knee osteoarthritis.

The heterogeneous nature of osteoarthritis (OA) and the need to subtype patients is widely accepted in the field. The biomarker CRPM, a metabolite of C-reactive protein (CRP), is released to the circulation during inflammation. Blood CRPM levels have shown to be associated with disease activity and response to treatment in rheumatoid arthritis (RA). We investigated the level of blood CRPM in OA compared to RA using data from two phase III knee OA and two RA studies (N = 1591). Moreover, the association between CRPM levels and radiographic progression was investigated. The mean CRPM levels were significantly lower in OA (8.5 [95% CI 8.3-8.8] ng/mL, n = 781) compared to the RA patients (12.8 [9.5-16.0] ng/mL, n = 60); however, a significant subset of OA patients (31%) had CRPM levels (≥ 9 ng/mL) comparable to RA. Furthermore, OA patients (n = 152) with CRPM levels ≥ 9 ng/mL were more likely to develop contra-lateral knee OA assessed by X-ray over a two-year follow-up period with an odds ratio of 2.2 [1.0-4.7]. These data suggest that CRPM is a blood-based biochemical marker for early identification OA patients with an inflammatory phenotype.

The effects of sprifermin on symptoms and structure in a subgroup at risk of progression in the FORWARD knee osteoarthritis trial.

OBJECTIVE: To assess pain outcomes and cartilage thickness change in a subgroup at risk (SAR) of further progression in the FORWARD trial of knee osteoarthritis patients treated with sprifermin. METHODS: Patients were randomised 1:1:1:1:1 to: sprifermin 100 µg every 6 months (q6mo), 100 µg q12mo, 30 µg q6mo, 30 µg q12mo, or placebo for 18 months. SAR was defined as baseline medial or lateral minimum joint-space width (mJSW) 1.5-3.5 mm and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score 40-90 units. Follow-up to 3 years was included in the analysis. Treatment benefit was explored by repeated measures, linear dose-effect trends by timepoint. RESULTS: The SAR comprised 161 (29%) of 549 patients. Mean difference (95% CI) in WOMAC pain at year 3 for sprifermin 100 µg q6mo vs placebo SAR was -8.75 (-22.42, 4.92) for SAR vs 0.97 (-6.22, 8.16) for the intent-to-treat population. SAR placebo patients lost more cartilage over 2 years than the modified ITT (mITT) placebo arm (mean change from baseline, mm [SD]: -0.05 [0.10] vs -0.02 [0.07]). Net total femorotibial joint thickness gain with sprifermin 100 µg q6mo (adjusted mean difference from placebo [95% CI] was similar in the SAR and in the mITT group: 0.06 [0.01, 0.11] vs 0.05 [0.03, 0.07]). CONCLUSIONS: Selection for low mJSW and moderate-to-high pain at baseline resulted in more rapid disease progression and demonstrated translation of structure modification (with maintained net benefit on total cartilage thickness) into symptomatic benefit. This subgroup may represent a target population for future trials. CLINICAL TRIAL REGISTRATION: NCT01919164.

A novel diclofenac gel (AMZ001) applied once or twice daily in subjects with painful knee osteoarthritis: A randomized, placebo-controlled clinical trial.

PURPOSE: Osteoarthritis Research Society International (OARSI) Expert Consensus Guidelines recommend topical non-steroidal anti-inflammatory drugs as first-line medications for osteoarthritis (OA) knee pain, but several voluminous daily applications are required to achieve efficacy. There is a need to develop new and improved topical analgesics with a faster onset, longer duration of action, and the requirement to apply less gel. This trial investigated the safety and efficacy of a new 3.06% diclofenac gel (AMZ001) in subjects with knee OA. METHODS: In total, 444 subjects (AMZ001 twice daily (BID) [n = 121], AMZ001 once daily (QD) + placebo QD [n = 121], placebo BID [n = 121], or Voltaren 1% 4-times daily [n = 81]) were enrolled. All except Voltaren 1% (single-blinded) were applied topically in a double-blind manner for a total of 4-weeks. The primary endpoint was the change from baseline to week 4 in the WOMAC pain sub-score in the target knee. Secondary and exploratory endpoints included additional efficacy measures (WOMAC total score, WOMAC function and stiffness sub-scores, WOMAC pain weight-bearing and non-weight-bearing sub-scores, ICOAP, chair-stand test, OMERACT-OARSI responder rate, PGA, WPAI, EQ-5D, rescue medication use, satisfaction questionnaire) and safety. RESULTS: Treatment with AMZ001 QD was effective at reducing WOMAC pain sub-scores vs placebo (estimated treatment difference [ETD]: -4.61 [95% confidence interval (CI): -9.09, -0.12]; p = 0.0440); however, BID application was not (ETD: -3.76 [95% CI: -8.21, 0.68]; p = 0.0969). For several secondary endpoints, changes from baseline to week 4 conferred nominally statistically significant improvements in favor of AMZ001 vs placebo, including PGA score (AMZ001 BID vs placebo, ETD: -0.61 [95% CI: -1.11, -0.11]; p = 0.0162; AMZ001 QD vs placebo, ETD: -0.63 [95% CI: -1.13, -0.13]; p = 0.0134), WPAI overall work impairment score (AMZ001 QD vs placebo, ETD: -10.44 [95% CI: -20.84, -0.04]; p = 0.0492), and EQ-5D VAS score (AMZ001 BID vs placebo, ETD: 4.70 [95% CI: 0.55, 8.85]; p = 0.0264). Post-hoc analysis excluding 11-14 subjects per group with pain scores that decreased between screening and baseline suggests a consistent effect of both AMZ001 QD (ETD: -5.84 [95% CI: -10.71, -0.97]; p = 0.0189) and BID (ETD: -5.35 [95% CI: -10.16, -0.54]; p = 0.0292) in reducing WOMAC pain sub-scores vs placebo. In general, treatment satisfaction was high, as measured by the satisfaction questionnaire. The frequency and incidence of adverse events (AEs) was greatest in the placebo group. Most AEs (>99%) were of mild or moderate severity. There were no serious AEs. There were no notable effects of any treatment on vital signs, ECGs, physical examination findings, or other laboratory assessments. CONCLUSIONS: Treatment with AMZ001 BID for 4 weeks improved WOMAC pain sub-scores; however, only QD application conferred nominally statistically significant improvements vs placebo. AMZ001 was generally well tolerated.

Clinical and biochemical factors associated with risk of total joint replacement and radiographic progression in osteoarthritis: Data from two phase III clinical trials.

OBJECTIVES: Clinical trials of new disease-modifying treatments for osteoarthritis should demonstrate a positive effect on a functional outcome or reduction in joint failure in order to be considered successful. Total joint replacement (TJR) surgery may be considered as joint failure, but great variation in the incidence of TJR complicates its use as a study endpoint. Factors predicting elevated risk of TJR could potentially be used to enrich such outcome-trials. METHODS: Using cumulative data from two phase three clinical trials with urine samples from 1255 knee OA patients followed for two years, we assessed the value of a series of baseline clinical variables including the uCTX-II biomarker, as predictors of joint-space narrowing, Kellgren-Lawrence-grade progression, and total joint replacement. RESULTS: A prediction-model incorporating age, sex, BMI, CTX-II and KL-grade predicted TJR within the two-year period with an AUC of 0.75 (95% CI: 0.72-0.77). The participants with a cumulative KL-grade between knees of 5, 6, or 7 had a more than 3 times higher risk of TJR in the study period compared to lower (HR: 3.03, 95% CI: 1.54 to 5.96, p = 0.001). Age was associated with increased TJR risk (per 5 years of age: HR: 1.28, 95% CI: 1.03-3.79, p = 0.05). Baseline u-CTX-II was associated with elevated risk of radiographic progression in terms of both JSN and KL-grade. CONCLUSIONS: A composite model combining baseline age, sex, BMI, u-CTX-II and KL-grade was able to acceptably predict TJR during a two-year period. In the absence of baseline radiographic OA severity, u-CTX-II independently contributed to prediction of TJR. Baseline urine CTX-II was associated with risk of radiographic progression.

Evaluation of serum ARGS neoepitope as an osteoarthritis biomarker using a standardized model for exercise-induced cartilage extra cellular matrix turnover.

Objective: To propose a standardized model for exercise-induced cartilage turnover and investigate residual levels and dynamics of biomarker serum ARGS (sARGS) in primary osteoarthritis (OA) patients and a supportive group of young healthy subjects. Method: The trial is a randomized, cross-over, exploratory study with interventions of exercise and inactivity. 20 subjects with knee OA, as well as 20 young healthy subjects (mean age 25.7 years (range; 19-30), 50% male), underwent cycling, running and resting interventions on separate days one week apart. Blood samples were taken at baseline, immediately, 1, 2, 3 and 24 h after activity start. sARGS was measured by sandwich ELISA. Results: Intraclass correlation between visits were 0.97 and 0.77 for the OA and healthy group, respectively. An acute drop in sARGS in response to high-intensity exercise was observed in both groups. Minute acute sARGS increase was observed in OA subjects in response to moderate intensity running and cycling, which normalized within 24 h. In healthy subjects an acute drop in sARGS was seen immediately after running, but not cycling, and no other changes were observed. A negative correlation between baseline Kellgren-Lawrence (KL) grade and baseline sARGS (r = -0.69, p = 0.002) in OA was found. A negative correlation between age and sARGS was found in healthy subjects (r = -0.67, p = <0.002). Conclusion: sARGS sensitivity to physical activity is considered low and sARGS is a reproducible and stable marker. Minute acute increases in sARGS were observed in the hours following moderate intensity exercise.

Effect of Intra-Articular Sprifermin vs Placebo on Femorotibial Joint Cartilage Thickness in Patients With Osteoarthritis: The FORWARD Randomized Clinical Trial.

Importance: Sprifermin is under investigation as a disease-modifying osteoarthritis drug. Objective: To evaluate the effects of sprifermin on changes in total femorotibial joint cartilage thickness in the more symptomatic knee of patients with osteoarthritis. Design, Setting, and Participants: FORWARD (FGF-18 Osteoarthritis Randomized Trial with Administration of Repeated Doses) was a 5-year, dose-finding, multicenter randomized clinical trial conducted at 10 sites. Eligible participants were aged 40 to 85 years with symptomatic, radiographic knee osteoarthritis and Kellgren-Lawrence grade 2 or 3. Enrollment began in July 2013 and ended in May 2014; the last participant visit occurred on May 8, 2017. The primary outcome at 2 years and a follow-up analysis at 3 years are reported. Interventions: Participants were randomized to 1 of 5 groups: intra-articular injections of 100 µg of sprifermin administered every 6 months (n = 110) or every 12 months (n = 110), 30 µg of sprifermin every 6 months (n = 111) or every 12 months (n = 110), or placebo every 6 months (n = 108). Each treatment consisted of weekly injections over 3 weeks. Main Outcomes and Measures: The primary end point was change in total femorotibial joint cartilage thickness measured by quantitative magnetic resonance imaging at 2 years. The secondary end points (of 15 total) included 2-year change from baseline in total Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores. The minimal clinically important difference (MCID) is unknown for the primary outcome; for total WOMAC score in patients with hip and knee osteoarthritis, the absolute MCID is 7 U (95% CI, 4 to 10 U) and the percentage MCID is 14% (95% CI, 9% to 18%). Results: Among 549 participants (median age, 65.0 years; 379 female [69.0%]), 474 (86.3%) completed 2-year follow-up. Compared with placebo, the changes from baseline to 2 years in total femorotibial joint cartilage thickness were 0.05 mm (95% CI, 0.03 to 0.07 mm) for 100 µg of sprifermin administered every 6 months; 0.04 mm (95% CI, 0.02 to 0.06 mm) for 100 µg of sprifermin every 12 months; 0.02 mm (95% CI, -0.01 to 0.04 mm) for 30 µg of sprifermin every 6 months; and 0.01 mm (95% CI, -0.01 to 0.03 mm) for 30 µg of sprifermin every 12 months. Compared with placebo, there were no statistically significant differences in mean absolute change from baseline in total WOMAC scores for 100 µg of sprifermin administered every 6 months or every 12 months, or for 30 µg of sprifermin every 6 months or every 12 months. The most frequently reported treatment-emergent adverse event was arthralgia (placebo: n = 46 [43.0%]; 100 µg of sprifermin administered every 6 months: n = 45 [41.3%]; 100 µg of sprifermin every 12 months: n = 50 [45.0%]; 30 µg of sprifermin every 6 months: n = 40 [36.0%]; and 30 µg of sprifermin every 12 months: n = 48 [44.0%]). Conclusions and Relevance: Among participants with symptomatic radiographic knee osteoarthritis, the intra-articular administration of 100 µg of sprifermin every 6 or 12 months vs placebo resulted in an improvement in total femorotibial joint cartilage thickness after 2 years that was statistically significant, but of uncertain clinical importance; there was no significant difference for 30 µg of sprifermin every 6 or 12 months vs placebo. Durability of response also was uncertain. Trial Registration: ClinicalTrials.gov Identifier: NCT01919164.

Associations between biomarkers of bone and cartilage turnover, gender, pain categories and radiographic severity in knee osteoarthritis.

BACKGROUND: Excessive cartilage degradation is a known characteristic of osteoarthritis (OA). Biochemical markers, such as uCTX-II, have been shown to be associated with disease severity, yet the tissue origin of CTX-II has been disputed. This analysis investigates the association between OA knee joints at different radiographic stages and pain categories with levels of uCTX-II and biomarkers of bone resorption and formation. METHODS: Baseline data of two randomised clinical trials (NCT00486434 and NCT00704847) in patients with radiographic OA and presence of pain were analysed post hoc. A subgroup with available urine samples and evaluable radiographs for both knees (N = 1241) was analysed. Urine CTX-I, urine CTX-II and serum osteocalcin were analysed for associations with combined Kellgren-Lawrence (KL) scores, gender and pain for both knees to assess the contribution of joints at different stages. RESULTS: Pain, BMI, age, gender and KL grade were all significantly associated with uCTX-II. The association between pain and CTX-II appeared to be driven by weight-bearing pain. The level of uCTX-II incrementally increased with higher radiographic severity of each knee. Levels of bone markers CTX-I and osteocalcin were both significantly associated with BMI and gender, but neither were associated with radiographic severity. Biomarker levels between male or female groups of identical KL scores were found to be higher in females compared to males in some but not all KL score groups. CONCLUSIONS: These results indicate that levels of uCTX-II are independently associated with radiographic severity of OA and pain intensity. CTX-II was associated with weight-bearing pain, but not non-weight-bearing pain, independent of co-variates. Bilateral OA knee joints appear to contribute to uCTX-II levels in an incremental manner according to radiographic severity of single joints. The data suggest that biomarker differences between genders should be taken into account when evaluating these markers in the context of structural features of OA.