Efficacy and safety of canakinumab treatment in schnitzler syndrome: A systematic literature review

Monitoring of Adverse Events and Safety in Autoinflammatory Diseases: Real-Life Data from the Eurofever Registry

OBJECTIVES

The study is aimed to evaluate the impact of safety events in the Eurofever registry for Autoinflammatory diseases.

METHODS

This was a retrospective and longitudinal observational multicentre study. Data were retrieved from the international registry Eurofever, starting patients' enrolment since 2009. All moderate, severe, or very severe AEs reported by treating physician in Eurofever were analyzed regardless of a possible suspected causal relationship to any therapies and according to the latest release of the Medical Dictionary for Regulatory Activities.

RESULTS

Complete information on safety were available in 2464 patients enrolled in the registry. In 1499 of them retrospective data encompassing the period from disease onset to enrolment were available, whereas 965 consecutive patients entered in the longitudinal part of the study. A total of 479 AEs have been reported in 275 patients. Eighty-two AEs were reported as serious and 99 were drug-related according to the physicians. Infections or infestations (94; 19.6%), gastrointestinal disorders (66; 13.8%), nervous system disorders (41; 8.6%) and systemic disorders or administration site reactions (35; 7.3%) were the most frequent reported events. The highest absolute number of drug-related AEs were related to biologic DMARDs (40/99 reports, 40,4%) and colchicine (31/99 reports, 31.3%).

CONCLUSIONS

Present study shows the importance of a longitudinal and homogeneous registration of the AEs in rare conditions, with a particular focus on the safety profile of the treatments used in these conditions.

Schnitzler syndrome refractory to anakinra: successful treatment with canakinumab

Schnitzler syndrome (SchS) is a rare autoimmune and inflammatory disease mediated by interleukin-1 beta (IL-1β). Recurrent monoclonal gammopathy and chronic urticarial rash are the symptoms required for diagnosis according to the Strasbourg criteria. The low prevalence of this syndrome (around 300 cases have been reported) and confusion with other inflammatory disorders may delay the diagnosis for up to 5 years. Although the most effective treatment for SchS is anakinra, some patients do not respond to this treatment. We report a case of SchS in a 64-year-old woman with multiple episodes of fever, severe rash, erythema, arthralgia and dyspnea. The patient was successfully treated with canakinumab after anakinra intolerance and failure of colchicine, prednisone, methotrexate and dapsone. After the first dose of canakinumab the skin wounds rapidly improved and the patient did not require any concomitant treatments. The cause of SchS is still unknown and a differential diagnosis is recommended, especially with adult-onset Still´s disease due to their similar symptoms. Canakinumab, a specific anti-IL-1β antibody, blocks its binding to receptors, thereby preventing IL-1β-induced gene activation and production of inflammatory mediators. Canakinumab has proven to be an effective drug in SchS, providing an alternative to anakinra.

Anti-Drug Antibodies in the Biological Therapy of Autoimmune Rheumatic Diseases

Autoimmune rheumatic diseases are a cluster of heterogeneous disorders that share some clinical symptoms such as pain, tissue damage, immune deregulation, and the presence of inflammatory mediators. Biologic disease-modifying antirheumatic drugs are some of the most effective treatments for rheumatic diseases. However, their molecular and pharmacological complexity makes them potentially immunogenic and capable of inducing the development of anti-drug antibodies. TNF inhibitors appear to be the main contributors to immunogenicity because they are widely used, especially in rheumatoid arthritis. Immunogenicity response on these treatments is crucial since the appearance of ADAs has consequences in terms of safety and efficacy. Therefore, this review proposes an overview of the immunogenicity of biological agents used in autoimmune rheumatic diseases highlighting the prevalence of anti-drug antibodies.

Improving Diagnosis and Clinical Management of Acquired Systemic Autoinflammatory Diseases

Systemic autoinflammatory diseases (SAID) are conditions caused by dysregulation or disturbance of the innate immune system, with neutrophils and macrophages the main effector cells. Although there are now more than 40 distinct, genetically defined SAIDs, the genetic/molecular diagnosis remains unknown for a significant proportion of patients with the disease onset in adulthood. This review focuses on new developments related to acquired/late onset SAID, including phenocopies of monogenic disorders, Schnitzler's syndrome, Adult onset Still's disease, VEXAS syndrome, and autoinflammatory complications associated with myelodysplastic syndrome.

Unmet Medical Needs in Chronic, Non-communicable Inflammatory Skin Diseases

An estimated 20-25% of the population is affected by chronic, non-communicable inflammatory skin diseases. Chronic skin inflammation has many causes. Among the most frequent chronic inflammatory skin diseases are atopic dermatitis, psoriasis, urticaria, lichen planus, and hidradenitis suppurativa, driven by a complex interplay of genetics and environmental factors. Autoimmunity is another important cause of chronic skin inflammation. The autoimmune response may be mainly T cell driven, such as in alopecia areata or vitiligo, or B cell driven in chronic spontaneous urticaria, pemphigus and pemphigoid diseases. Rare causes of chronic skin inflammation are autoinflammatory diseases, or rheumatic diseases, such as cutaneous lupus erythematosus or dermatomyositis. Whilst we have seen a significant improvement in diagnosis and treatment, several challenges remain. Especially for rarer causes of chronic skin inflammation, early diagnosis is often missed because of low awareness and lack of diagnostics. Systemic immunosuppression is the treatment of choice for almost all of these diseases. Adverse events due to immunosuppression, insufficient therapeutic responses and relapses remain a challenge. For atopic dermatitis and psoriasis, a broad spectrum of innovative treatments has been developed. However, treatment responses cannot be predicted so far. Hence, development of (bio)markers allowing selection of specific medications for individual patients is needed. Given the encouraging developments during the past years, we envision that many of these challenges in the diagnosis and treatment of chronic inflammatory skin diseases will be thoroughly addressed in the future.

Schnitzler syndrome and Schnitzler-like syndromes

Schnitzler syndrome is a rare disease of adult-onset with main features including chronic urticarial rash, recurrent fever, arthralgia or arthritis, monoclonal gammopathy of undetermined significance (MGUS), and marked systemic inflammation. Schnitzler syndrome is often underdiagnosed. Patients with Schnitzler syndrome may present to dermatologists and allergists for urticaria, hematologists for MGUS, or rheumatologists for arthritis. It is important to recognize Schnitzler syndrome for its remarkable response to interleukin (IL)-1 blockade. Besides, many cases of Schnitzler-like syndromes do not meet the diagnostic criteria of classical Schnitzler syndrome but display excellent response to IL-1 inhibitors. The overly produced IL-1 is the result of a somatic mosaic gain of function mutation of NLRP3 (nucleotide-binding oligomerization domain [NOD]-like receptor [NLR] family pyrin domain containing 3) gene in some patients with Schnitzler-like syndromes. Inflammasome activation is evident in patients with classical Schnitzler syndrome although no NLRP3 gene mutation is identified. Collectively, Schnitzler syndrome and Schnitzler-like syndromes represent a spectrum of IL-1 mediated adult-onset autoinflammatory diseases.

Soluble Factors and Receptors Involved in Skin Innate Immunity-What Do We Know So Far?

The pattern recognition receptors, complement system, inflammasomes, antimicrobial peptides, and cytokines are innate immunity soluble factors. They sense, either directly or indirectly, the potential threats and produce inflammation and cellular death. High interest in their modulation has emerged lately, acknowledging they are involved in many cutaneous inflammatory, infectious, and neoplastic disorders. We extensively reviewed the implication of soluble factors in skin innate immunity. Furthermore, we showed which molecules target these factors, how these molecules work, and how they have been used in dermatological practice. Cytokine inhibitors have paved the way to a new era in treating moderate to severe psoriasis and atopic dermatitis.