Onset and maintenance of efficacy of subcutaneous tanezumab in patients with moderate to severe osteoarthritis of the knee or hip: A 16-week dose-titration study

The potential role of synovial cells in the progression and treatment of osteoarthritis

Osteoarthritis (OA), the commonest arthritis, is characterized by the progressive destruction of cartilage, leading to disability. The Current early clinical treatment strategy for OA often centers on anti-inflammatory or analgesia medication, weight loss, improved muscular function and articular cartilage repair. Although these treatments can relieve symptoms, OA tends to be progressive, and most patients require arthroplasty at the terminal stages of OA. Recent studies have shown a close correlation between joint pain, inflammation, cartilage destruction and synovial cells. Consequently, understanding the potential mechanisms associated with the action of synovial cells in OA could be beneficial for the clinical management of OA. Therefore, this review comprehensively describes the biological functions of synovial cells, the synovium, together with the pathological changes of synovial cells in OA, and the interaction between the cartilage and synovium, which is lacking in the present literature. Additionally, therapeutic approaches based on synovial cells for OA treatment are further discussed from a clinical perspective, highlighting a new direction in the treatment of OA.

Biological Therapy for Osteoarthritis, Efficacy and Safety: Focus on Monoclonal Antibodies against Nerve Growth Factor and Fibroblast Growth Factor-18

Osteoarthritis (OA) is the most common chronic progressive musculoskeletal disease, affected cartilage, and surrounded tissues: Subchondral bones, ligaments, and meniscus. Current OA treatment based on non-steroidal anti-inflammatory drugs, acetaminophen (paracetamol), opioids, and intra-articular corticosteroid injections do not prevent the progression of the disease. Understanding of the pathogenesis of OA with continued structural damage accompanied by chronic pain led to appearance of monoclonal antibodies to fibroblast growth factor-18 (FGF)-18 and anti-nerve growth factor (NGF). This review provides an overview of biological therapy with FGF-18 and anti-NGF for OA. Search process was conducted in PubMed and Google Scholar for the following terms: “FGF-18” or “anti-NGF” and “OA,” “monoclonal antibody” and “OA.” Results of the analysis of clinical trials revealed that therapy targeting NGF resulted in significant analgesic effect and functional improvement of joints in OA; however, it was associated with considerable increase in adverse events. The mon\oclonal antibody to FGF-18 demonstrated the structure-modifying effects on cartilage with decrease the cartilage loss and improvement of cartilage thickness. However, further clinical longitudinal studies characterized the risk-benefit are needed to establish safety and efficacy of these medications.

Observed efficacy and clinically important improvements in participants with osteoarthritis treated with subcutaneous tanezumab: results from a 56-week randomized NSAID-controlled study

BACKGROUND

A recent phase 3 study demonstrated that treatment with tanezumab, a nerve growth factor inhibitor, or nonsteroidal anti-inflammatory drugs (NSAIDs) improves pain and physical function in participants with moderate-to-severe osteoarthritis (OA) of the hip or knee. Here, we evaluated the time course and clinical importance of these initial efficacy findings using a mixture of primary, secondary, and post hoc endpoints.

METHODS

Participants on stable NSAID therapy and with a history of inadequate response to other standard OA analgesics were enrolled in an 80-week (56-week treatment/24-week safety follow-up), randomized, NSAID-controlled, phase 3 study primarily designed to assess the safety of tanezumab for moderate-to-severe OA of the knee or hip. Participants received oral NSAID (twice daily naproxen, celecoxib, or diclofenac) or subcutaneous tanezumab (2.5mg or 5mg every 8 weeks). Non-responders were discontinued at week 16. Changes from baseline in WOMAC Pain and Physical Function, Patient's Global Assessment of Osteoarthritis (PGA-OA), and average pain in the index joint were compared between tanezumab and NSAID groups over the 56-week treatment period. Clinically meaningful response (e.g., ≥30% and ≥50% improvement in WOMAC Pain and Physical Function), rescue medication use, and safety were also assessed.

RESULTS

All groups improved WOMAC Pain, WOMAC Physical Function, PGA-OA, and average pain in the index joint over the 56-week treatment period relative to baseline. Across all groups, improvements generally occurred from the time of first assessment (week 1 or 2) to week 16 and then slightly decreased from week 16 to 24 before stabilizing from weeks 24 to 56. The magnitude of improvement and the proportion of participants achieving ≥30% and ≥50% improvement in these measures was greater (unadjusted p≤0.05) with tanezumab than with NSAID at some timepoints on or before week 16. Adverse events of abnormal peripheral sensation, prespecified joint safety events, and total joint replacement surgery occurred more frequently with tanezumab than with NSAID.

CONCLUSIONS

Tanezumab and NSAID both provided early and sustained (up to 56 weeks) efficacy relative to baseline. Improvements in pain and function were clinically meaningful in a substantial proportion of participants. Adverse events of abnormal peripheral sensation and joint safety events occurred more frequently with tanezumab than with NSAID.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02528188 . Registered on 19 July 2015.

Relative Efficacy and Safety of Tanezumab for Osteoarthritis: A Systematic Review and Meta-analysis of Randomized-Controlled Trials

OBJECTIVES

The aim of this meta-analysis was to evaluate the efficacy and safety of tanezumab for the treatment of patients with knee or hip osteoarthritis (OA).

METHODS

PubMed, Embase, Cochrane Central Register of Controlled Trials, and Web of Science were searched from inception to July 2020. Randomized-controlled trials comparing tanezumab with placebo or nonsteroidal anti-inflammatory drugs in patients with OA. Two investigators identified studies and independently extracted data, and conventional meta-analyses were conducted with Review Manager 5.3. The outcomes were pain relief, functional improvement, and risk of adverse events (AEs).

RESULTS

A total of 8 articles, comprising 9 randomized-controlled trials, were included. Overall, tanezumab was superior to placebo for relieving pain and improving function, as well as in the patient's global assessment. Tanezumab also had significant advantages over nonsteroidal anti-inflammatory drugs for relieving pain and improving function, as well as in the patient's global assessment. Significantly more patients discontinued treatment because of AEs after treatment with tanezumab. However, the differences in serious AEs and total joint replacement were not significant. Moreover, tanezumab-treated patients experienced significantly more rapid progression of osteoarthritis.

DISCUSSION

Tanezumab can alleviate pain and improve function for patients with OA of the hip or knee. Although tanezumab does not cause serious AEs, rapid progression of OA occurred in a small number of participants, so more clinical trials are needed to explore its safety.

Nerve Growth Factor (NGF) Inhibitors and Related Agents for Chronic Musculoskeletal Pain: A Comprehensive Review

Musculoskeletal pain such as osteoarthritis (OA) and low back pain (LBP) are very common and contribute to enormous burden and societal costs, despite dramatic therapeutic advances over recent decades. Novel approaches and targeted therapies are required to satisfy the urgent unmet medical need of musculoskeletal pain relief in both conditions. Nerve growth factor (NGF) inhibitors have utilized novel mechanisms different from conventional drugs, which have a variety of gastrointestinal, cardiac, or renal adverse effects. Several phase 2/3 studies have been accomplished for these drugs, such as tanezumab, fasinumab, and tyrosine receptor kinase A (TrkA) inhibitors. We searched the literature using the PubMed database and clinical trials using ClinicalTrials.gov to identify original papers, meta-analyses as well as ongoing clinical trials assessing the efficacy and safety profile of these drugs. In this narrative review, we briefly overview the disease burden of musculoskeletal pain, the role of NGF signaling and its receptors in the genesis of pain, and the mechanisms of action of inhibitors of NGF signaling and downstream pathways, and then discuss the efficacy and safety of each investigational drug in OA and LBP. Finally, we briefly review two serious adverse effects of NGF inhibitors, namely rapidly progressive OA and sympathetic system effects, and conclude with possible barriers and potential research directions to overcome these.

Single and Composite Endpoints of Within-Patient Improvement in Symptoms: Pooled Tanezumab Data in Patients with Osteoarthritis

INTRODUCTION

Combining measures of key core domains (especially pain and function) into a composite endpoint that requires each patient to meet a threshold of improvement for each domain provides information on multiple aspects of osteoarthritis within individual patients. This pooled analysis of two phase 3 studies (NCT02697773, NCT02709486) explored single and composite endpoints for assessing within-patient improvement in knee or hip osteoarthritis symptoms following subcutaneous administration of tanezumab or placebo.

METHODS

Endpoints at week 16 included proportions of responders (≥ 30% improvement) in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain, WOMAC Physical Function, WOMAC Pain/Function composite, and weekly average pain; and patient acceptable symptom state (PASS) composite responders, minimal clinically important improvement (MCII) composite responders, Outcome Measures in Rheumatology-Osteoarthritis Research Society International (OMERACT-OARSI) responders, and sustained weekly average pain responders.

RESULTS

Pooled population comprised 1545 patients. Of patients who had a ≥ 30% improvement in WOMAC Pain and/or WOMAC Physical Function, 88.5% were WOMAC Pain/Function composite responders, 7.0% were WOMAC Pain (but not Function) responders, and 4.4% were WOMAC Function (but not Pain) responders. Of weekly average pain responders, 43.1% were PASS composite responders. Odds ratios (tanezumab 2.5 mg and 5 mg groups, respectively, vs placebo) were 1.75 and 1.86 (WOMAC Pain/Function composite responders), 1.41 and 1.65 (weekly average pain responders), 1.60 and 1.73 (PASS composite responders), 1.52 and 1.68 (MCII composite responders), 1.75 and 1.88 (OMERACT-OARSI responders), and 1.85 and 1.48 (sustained weekly average pain responders). Subgroup analyses suggested a greater magnitude of effect for patients with a knee index joint compared with hip on some endpoints.

CONCLUSION

Responders on single pain endpoints were in many cases also responders on function or composite endpoints. Separation of tanezumab from placebo was similar and consistent across single and composite endpoints.

Monoclonal Antibodies for Chronic Pain Treatment: Present and Future

Chronic pain remains a major problem worldwide, despite the availability of various non-pharmacological and pharmacological treatment options. Therefore, new analgesics with novel mechanisms of action are needed. Monoclonal antibodies (mAbs) are directed against specific, targeted molecules involved in pain signaling and processing pathways that look to be very effective and promising as a novel therapy in pain management. Thus, there are mAbs against tumor necrosis factor (TNF), nerve growth factor (NGF), calcitonin gene-related peptide (CGRP), or interleukin-6 (IL-6), among others, which are already recommended in the treatment of chronic pain conditions such as osteoarthritis, chronic lower back pain, migraine, or rheumatoid arthritis that are under preclinical research. This narrative review summarizes the preclinical and clinical evidence supporting the use of these agents in the treatment of chronic pain.

Selective Expression of a SNARE-Cleaving Protease in Peripheral Sensory Neurons Attenuates Pain-Related Gene Transcription and Neuropeptide Release

Chronic pain is a leading health and socioeconomic problem and an unmet need exists for long-lasting analgesics. SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptors) are required for neuropeptide release and noxious signal transducer surface trafficking, thus, selective expression of the SNARE-cleaving light-chain protease of botulinum neurotoxin A (LCA) in peripheral sensory neurons could alleviate chronic pain. However, a safety concern to this approach is the lack of a sensory neuronal promoter to prevent the expression of LCA in the central nervous system. Towards this, we exploit the unique characteristics of Pirt (phosphoinositide-interacting regulator of TRP), which is expressed in peripheral nociceptive neurons. For the first time, we identified a Pirt promoter element and cloned it into a lentiviral vector driving transgene expression selectively in peripheral sensory neurons. Pirt promoter driven-LCA expression yielded rapid and concentration-dependent cleavage of SNAP-25 in cultured sensory neurons. Moreover, the transcripts of pain-related genes (TAC1, tachykinin precursor 1; CALCB, calcitonin gene-related peptide 2; HTR3A, 5-hydroxytryptamine receptor 3A; NPY2R, neuropeptide Y receptor Y2; GPR52, G protein-coupled receptor 52; SCN9A, sodium voltage-gated channel alpha subunit 9; TRPV1 and TRPA1, transient receptor potential cation channel subfamily V member 1 and subfamily A member 1) in pro-inflammatory cytokines stimulated sensory neurons were downregulated by viral mediated expression of LCA. Furthermore, viral expression of LCA yielded long-lasting inhibition of pain mediator release. Thus, we show that the engineered Pirt-LCA virus may provide a novel means for long lasting pain relief.

The Role of Anti-Nerve Growth Factor Monoclonal Antibodies in the Control of Chronic Cancer and Non-Cancer Pain

Nerve growth factor (NGF) belongs to the neurotrophin family and plays a fundamental role in the endurance of sensory and sympathetic neurons during embryogenesis. NGF, by interacting with tropomyosin receptor kinase A receptor (TrkA), modulates the pain pathway through the enhancement of the neurotrophic and nociceptor functions. Moreover, it has been demonstrated that NGF is upregulated in patients with chronic pain syndromes, which are difficult to treat. Thus, new non-pharmacological approaches, based on the use of different species-specific monoclonal antibodies (mAbs) targeting the NGF pathway, have been tested for the treatment of chronic pain in preclinical and clinical studies. With regard to preclinical investigations, anti-NGF mAbs have been used for the management of osteoarthritis (OA) and chronic low back pain animal models, with encouraging results. Moreover, anti-NGF mAb therapy is effective in animal models of neuropathic cancer pain. As regards patients with OA, although phase II and phase III clinical trials with tanezumab led to pain reduction, the safety was not observed in all these patients. Here, we review the preclinical and clinical studies on anti-NGF mAb therapy in chronic syndromes, dissect the role of NGF in pain transduction, and highlight the use of anti-NGF mAbs in humans.

Subcutaneous tanezumab for osteoarthritis: Is the early improvement in pain and function meaningful and sustained?

Background

To evaluate if early improvements in pain and function with subcutaneous tanezumab are meaningful and sustained over 24 weeks.

Methods

Patients with moderate‐to‐severe osteoarthritis (hip or knee) in Europe and Japan were randomized to placebo, tanezumab 2.5 mg or tanezumab 5 mg (baseline, Week 8 and Week 16). Outcomes included: average daily index joint pain score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) subscales, rescue medication use, WOMAC responders (within‐patient ≥30% reduction in WOMAC Pain or Physical Function), Outcome Measures in Rheumatology‐Osteoarthritis Research Society International (OMERACT‐OARSI) responders (within‐patient) and Patient‐reported Treatment Impact Assessment‐Modified questionnaire.

Results

Patients received placebo (n = 282), tanezumab 2.5 mg (n = 283) or tanezumab 5 mg (n = 284). Changes from baseline in average daily index joint pain (within the first week) and WOMAC subscales (Week 2 through Week 24) were greater for each tanezumab group versus placebo (least squares [LS] mean, unadjusted p ≤ .05). Rescue medication use (days/week) was lower for each tanezumab group versus placebo from Week 2 through Week 12 (LS mean, unadjusted p ≤ .05) but not at Week 16 or 24. A higher proportion of each tanezumab group than placebo achieved ≥30% reduction from baseline in WOMAC Pain or Physical Function, or OMERACT‐OARSI response (Week 2 through Week 24, unadjusted p ≤ .05), or were satisfied with treatment at Week 24 (unadjusted p ≤ .05).

Conclusions

Subcutaneous tanezumab, compared with placebo, reduced pain within the first week, and pain and function were improved throughout 24 weeks. The proportions of responders and patients satisfied were higher with tanezumab than placebo.

ClinicalTrials.gov:NCT02709486.

Significance

This exploratory analysis of data from a placebo‐controlled, Phase 3 study of patients with moderate‐to‐severe osteoarthritis of the hip or knee for whom standard analgesics were not effective or could not be taken, found that onset of efficacy of subcutaneous tanezumab was within the first week, and efficacy was maintained through the 24‐week treatment period. Tanezumab was effective in those patients with the most radiologically severe osteoarthritis.

Neuroscience and Neuroimmunology Solutions for Osteoarthritis Pain: Biological Drugs, Growth Factors, Peptides and Monoclonal Antibodies Targeting Peripheral Nerves

Neuroscience is a vast discipline that deals with the anatomy, biochemistry, molecular biology, physiology and pathophysiology of central and peripheral nerves. Advances made through basic, translational, and clinical research in the field of neuroscience have great potential for long-lasting and beneficial impacts on human and animal health. The emerging field of biological therapy is intersecting with the disciplines of neuroscience, orthopaedics and rheumatology, creating new horizons for interdisciplinary and applied research. Biological drugs, growth factors, therapeutic peptides and monoclonal antibodies are being developed and tested for the treatment of painful arthritic and rheumatic diseases. This concise communication focuses on the solutions provided by the fields of neuroscience and neuroimmunology for real-world clinical problems in the field of orthopaedics and rheumatology, focusing on synovial joint pain and the emerging biological treatments that specifically target pathways implicated in osteoarthritis pain in peripheral nerves.

The evolution of nerve growth factor inhibition in clinical medicine

Nerve growth factor (NGF) is a neurotrophin that activates nociceptive neurons to transmit pain signals from the peripheral to the central nervous system and that exerts its effects on neurons by signalling through tyrosine kinase receptors. Antibodies that inhibit the function of NGF and small molecule inhibitors of NGF receptors have been developed and tested in clinical studies to evaluate the efficacy of NGF inhibition as a form of analgesia in chronic pain states including osteoarthritis and chronic low back pain. Clinical studies in individuals with painful knee and hip osteoarthritis have revealed that NGF inhibitors substantially reduce joint pain and improve function compared with NSAIDs for a duration of up to 8 weeks. However, the higher tested doses of NGF inhibitors also increased the risk of rapidly progressive osteoarthritis in a small percentage of those treated. This Review recaps the biology of NGF and the studies that have been performed to evaluate the efficacy of NGF inhibition for chronic musculoskeletal pain states. The adverse events associated with NGF inhibition and the current state of knowledge about the mechanisms involved in rapidly progressive osteoarthritis are also discussed and future studies proposed to improve understanding of this rare but serious adverse event.