Telitacicept Following Plasma Exchange in the Treatment of Subjects With Recurrent NMOSD: Study Protocol for a Single-Center, Single-Arm, Open-Label Study

Refractory lupus hepatitis successfully treated with telitacicept who failed to belimumab: A case report and literature review

Background: Systemic lupus erythematosus (SLE)-associated hepatitis ("lupus hepatitis") was one of the most frequent causes of liver function abnormalities in patients with SLE. Lupus hepatitis (LH) is commonly treated with conventional treatment, including non-steroidal anti-inflammatory drugs, corticosteroids, and immunomodulators. However, in refractory cases, other treatment options may be required.Methodology: We report the case of a patient with lupus hepatitis refractory to both conventional therapy and belimumab who was successfully treated with telitacicept, a new dual B lymphocyte stimulator (BLyS)/APRIL (a proliferation-inducing ligand) inhibitor.Literature review was performed on PubMed search forum.Result: The specific search term was "telitacicept", 23 papers were searched, among them 10 case reports/series articles reporting telitacicept treatment were elected.Apart from our literature reporting the effectiveness of telitacicept in treating LH, there is no report on it in treating LH.Conclusion: This case suggests that telitacicept should be an effective and safe treatment for LH refractory, even to those who failed to belimumab based on the standard treatment, and can reduce the dosage of glucocorticoids.However, further investigations, particularly prospective randomized controlled trials, are warranted to verify our findings and ensure patient safety.

Role of telitacicept in the treatment of IgA nephropathy

IgA nephropathy (IgAN) is the most common primary glomerular disease in the world, and up to 40% of patients with IgAN develop end-stage renal disease (ESRD). At present, an increasing amount of evidence indicates that the pathogenesis of IgAN is related to autoimmunity. In recent years, several studies have shown that B cell activating factors (BAFF), also known as B lymphocyte stimulators (BLyS), and proliferation-inducing ligand APRIL are extremely important for the activation of autoimmune signalling pathways, which have become key targets for the treatment of IgAN. As a dual-target biological agent, telitacicept can inhibit both BLyS and APRIL cytokines, improve the function of renal immune complexes, and reduce haematuria and proteinuria, which play important roles in IgAN pathogenesis and long-term prognosis. This article reviews the role of telitacicept in IgA nephropathy and discusses its potential for use in the treatment of IgAN and other autoimmune diseases where pathogenesis is driven by B cells.

Telitacicept for autoimmune nephropathy

B cells and the humoral immunity are important players in the pathogenesis of autoimmune diseases. BAFF (also known as BLYS) and a proliferation-inducing ligand APRIL are required for the maintenance of the B-cell pool and humoral immunity. BAFF and APRIL can promote B-cell differentiation, maturation, and plasma cell antibody secretion. BAFF/APRIL overexpression has been identified in several autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, IgA nephropathy, etc. Telitacicept, a novel fully human TACI-Fc fusion protein that binds both BAFF and APRIL, was approved in China in March 2021 for the treatment of systemic lupus erythematosus at a recommended dose of 160 mg/w subcutaneously and is in clinical trials for the treatment of multiple indications in other autoimmune diseases. In this review, we explored telitacicept's mechanism of action and clinical data. In addition, the immune features of autoimmune nephropathy were discussed, emphasizing lupus nephritis, IgA nephropathy, and membranous nephropathy.

Telitacicept following plasma exchange in the treatment of subjects with recurrent neuromyelitis optica spectrum disorders: A single‐center, single‐arm, open‐label study

Introduction

Neuromyelitis optica spectrum disorders (NMOSD), mainly mediated by B cells and AQP4 antibody, has a high rate of recurrence. Telitacicept is a novel drug specifically targeting the upstream signaling for the activation of B cell with its following production of autoimmune antibodies. Thus, it may be a promising approach. Our study preliminarily explored the potential safety and effectiveness of Telitacicept following plasma exchange in the treatment of recurrent NMOSD.

Methods

This was a single‐center, single‐arm, open‐label study enrolling eight patients with recurrent NMOSD in China. All patients received plasma exchange three times, followed by Telitacicept 240 mg every week for 46 times. The primary endpoint was the time of first recurrence after enrollment. Secondary end points included: changes in Expanded Disability Status Scale score, Optic Spinal Impairment Scale score, Hauser Ambulation Index, number of lesions on MRI, retinal nerve fiber layer thickness measured by optical coherence tomography, latency and amplitude of visual evoked potential, titer of AQP4 antibody, and immune parameters of blood. Safety was also assessed. The study was registered with Chictr.org.cn (ChiCTR1800019427).

Results

Eight eligible patients were enrolled. Relapse occurred in two patients (25%) and five patients (63%) remained relapse free after 48 weeks of treatment. The time to first recurrence was prolonged and the number of recurrences was reduced (p < 0.001, power of test = 1). One patient withdrew from the study due to low neutrophil count. No serious adverse events occurred.

Conclusions

In this small, uncontrolled study, Telitacicept following plasma exchange has the potential to be a safe treatment for patients with recurrent NMOSD. It may prolong the recurrence interval and reduces the annual count of recurrences. A multicenter randomized controlled study with a larger sample is thus feasible and needed to further assess its safety and efficacy.

Safety and efficacy of telitacicept in refractory childhood-onset systemic lupus erythematosus: A self-controlled before–after trial

Objective

To observe the efficacy and safety of telitacicept in refractory childhood-onset systemic lupus erythematosus (cSLE).

Methods

A self-controlled before–after trial. Children with active SLE, aged 5–18 years, who cannot tolerate side effects of glucocorticoid, were enrolled in our study. Patients received subcutaneous injection of telitacicept weekly based on the standard treatment. SLE responder index-4 (SRI-4) was assessed before the first administration and at least 4 weeks after the first administration.

Results

Among the 15 cases of refractory cSLE, three were males (20%) and 12 were females (80%). The median age and weight were 13 years old and 52 kg, respectively. The median duration of disease was 30 months. 5–26 weeks (80 or 160 mg per week) after administration of telitacicept, 66.7% ( n=10) reached SRI-4 response. 12 cases reduced their glucocorticoid intake from 40 mg/d to 17.5 mg/d. The urinary protein after treatment declined in 8 cases whose 24-h proteinuria was >0.5 g at baseline. The urinary protein in two of the eight cases turned negative and plasma albumin in five of the eight cases rose to normal. In addition, three of these eight cases demonstrated varying degrees of improvement in renal impairment, whose estimated glomerular filtration rate (eGFR, ml/min·1.73 m2) rose from 17.4 to 26.6, 40.7 to 48.2, and 63.2 to 146.0, respectively. There were mild to moderate adverse events after treatment.

Conclusion

Telitacicept combined with the standard treatment may significantly increase the SRI-4 response rate and reduce the glucocorticoid dosage in refractory cSLE, and also shown efficacy on lupus nephritis. The related adverse drug events were controllable.

Telitacicept as a BLyS/APRIL dual inhibitor for autoimmune disease

The pathogenic roles for B cells in autoimmunity include produce pathogenic autoantibodies and modulate immune responses via the production of cytokines and chemokines. The B lymphocyte stimulator BLyS (also known as B-cell-activating factor, BAFF) and APRIL (a proliferation-inducing ligand) are critical factors in the maintenance of the B-cell pool and humoral immunity, namely BLyS modulates the differentiation and maturation of immature B cell, while APRIL modulates the function and survival of long-lived plasma cell, which plays a prominent role in the pathogenesis of autoimmune diseases. Telitacicept is a novel recombinant fusion protein of both the ligand-binding domain of the TACI receptor and the Fc component of human IgG and which is a BLyS/APRIL dual inhibitor. Moreover, telitacicept was developed by Remegen Co., Ltd. in China and is approved to treat systemic lupus erythematosus in China. We review the rationale, clinical evidence, and future perspectives of telitacicept for the treatment of autoimmune disease.HighlightThe B lymphocyte stimulator BLyS (also known as B-cell-activating factor, BAFF) and APRIL (a proliferation-inducing ligand), members of tumor necrosis factor (TNF) family, and which are critical factors in the maintenance of the B-cell pool and humoral immunity.BAFF and APRIL are implicated in the pathogenesis of several human autoimmune diseases with autoreactive B-cell involvement, and targeting both is beneficial for the treatment of autoimmune diseases.Telitacicept is a novel recombinant fusion protein of both the ligand-binding domain of the TACI receptor and the Fc component of human IgG, as a BLyS/APRIL dual inhibitor and which has been approved by National Medical Products Administration (MNPA) for the treatment of patients with SLE in China.With more clinical trials underway, telitacicept may also be approved for the treatment of other autoimmune diseases in the future.

Case Report: In Situ Expression of a Proliferation-Inducing Ligand in Neuromyelitis Optica

A proliferation inducing ligand (APRIL) mediates a key role in the generation and survival of antibody-inducing plasmocytes. Based on this, APRIL has been targeted in autoimmune diseases including multiple sclerosis (MS) and optic neuritis (ON). In MS lesions, APRIL has a new cellular target, the reactive astrocyte and mediates an immunosuppressive activity. Here, we analyzed APRIL expression in a case of neuromyelitis optica (NMO), another autoimmune neurodegenerative disease, showing selective aquaporin-4 depletion in the spinal cord, complement deposition and infiltration of polymorphonuclear cells. We analyzed by immunohistochemistry the presence of APRIL-producing cells, plasmocytes, astrocytes and the localization of secreted APRIL in a lesion from NMO. Plasmocytes were present close to APRIL-producing cells in meninges. However, our main observation was that APRIL targets reactive astrocytes in this lesion of NMO similarly to MS.

The number 13 of the family: a proliferation inducing ligand

The TNF superfamily member a proliferation inducing ligand (APRIL, TNFSF13) plays a late role in humoral immunity at the level of antibody-producing plasmocytes. The recent characterization of the first immunodeficient patient with an inactivating mutation in the APRIL gene provided the last piece of functional data lacking in the human system. Based on this function, APRIL has been considered as a valuable target to dampen unwanted antibody production. After reviewing the late data acquired on the physiological function of APRIL in humoral immunity, we will here review the state of the art regarding APRIL targeting in autoimmune diseases.

Comparative analysis of clinical and imaging data between patients with myelin oligodendrocyte glycoprotein antibody disease and patients with aquaporin 4 antibody-positive neuromyelitis optica spectrum disorder

BACKGROUND

We aimed to compare the clinical data, laboratory findings, and imaging characteristics of myelin oligodendrocyte glycoprotein antibody disease (MOGAD) and aquaporin 4 antibody (AQP4)-positive neuromyelitis optica spectrum disorder (NMOSD), as detailed comparative analyses of laboratory data for both diseases are rare.

METHODS

Our retrospective study compared the clinical data, laboratory findings, and imaging characteristics of 118 AQP4-positive patients with first-episode NMOSD and 25 patients with first-episode MOGAD. Logistic regression was used to determine the factors that differentiated MOGAD and AQP4-positive NMOSD.

RESULTS

There were significant differences in age, symptoms, recurrence rate, laboratory indicators, and imaging examinations between patients with MOGAD and patients with AQP4-positive NMOSD. Patients with MOGAD were younger and had higher levels of uric acid than those with AQP4-positive NMOSD. The proportion of cortical gray matter/juxtacortical white matter lesions was significantly higher in the MOGAD group than in the NMOSD group. Logistic regression revealed that young age [odds ratio (OR) = 0.947, 95% confidence interval (CI) = 0.905-0.99], high uric acid level (OR = 1.016, 95% CI = 1.006-1.027), and cortical gray matter/juxtacortical white matter involvement (OR = 3.889, 95% CI = 1.048-14.442) were significantly related to MOGAD.

CONCLUSION

The multivariate analysis of the present study demonstrated that age, uric acid level, and the presence of lesions in the cortical gray matter/juxtacortical white matter can aid in distinguishing patients with AQP4-positive NMOSD from those with MOGAD. These factors may also aid in determining which patients should be tested for antibodies.