OBJECTIVE: Juvenile arthritis caused by loss-of-function LACC1 mutations is characterized by early onset of symmetric and chronic arthritis, associated with an elevation of inflammatory markers. We aimed to describe serum cytokine levels, explore the type I interferon pathway, and evaluate the efficacy of treatment in a patient presenting with polyarthritis and anemia caused by novel compound heterozygous variations in LACC1.
METHODS: Clinical data of a patient with compound heterozygous variations in LACC1 was collected. Serum cytokine levels and IFN-stimulated cytokine genes were analyzed at diagnosis, at disease flare, and after treatment. Full-length cDNA of LACC1 was checked by RNA analysis. Single-cell RNA sequencing was performed in PBMCs.
RESULTS: Two novel variants in the LACC1 gene were identified in a patient presenting with polyarthritis and anemia. LACC1-cDNA was normally expressed in the healthy control, the target production at 1384 bp was not observed in the patient. Compared to nine patient controls with non-systemic juvenile idiopathic arthritis, serum interleukin(IL)-6 level was significantly elevated in the affected patient. The median IFN score for the patient, her mother, and controls were 118, 8, and 4.9, respectively. The combined treatment of JAK inhibitors with prednisone or tocilizumab led to a complete response, including remission of joint symptoms, resolution of anemia, reduced expression of IFN-stimulated cytokine genes, and normalized levels of inflammatory markers, including CRP, ESR, SAA, and serum IL-6.
CONCLUSIONS: LACC1 may play a crucial role in multiple inflammatory signaling pathways. The combination therapy of JAK inhibitors and tocilizumab may be effective for a subset of refractory patients.

Granulomatous tubulointerstitial nephritis (GTIN) attributed to early onset sarcoidosis is an ultrarare finding in an allograft kidney biopsy. We present the case of a young man with allograft dysfunction who had GTIN upon biopsy. We performed a thorough case review based on recovered records from early childhood and reassessed genetic testing results. We revised his underlying diagnosis from cryopyrin-associated periodic syndrome to early-onset sarcoidosis with wild-type NOD2 and established a rationale to use the interleukin-6 (IL-6) receptor blocker tocilizumab (TCZ). This suppressed his inflammatory disease and stabilised kidney function. We performed a literature review related to the emerging role of IL-6 pathway blockade in kidney transplantation. We identified 18 reports with 417 unique patients treated with TCZ for indications including HLA-desensitisation, transplant immunosuppression induction, treatment of chronic antibody-mediated rejection, and treatment of subclinical rejection. Both TCZ and the direct IL-6 inhibitor clazakizumab are being studied in ongoing randomised control trials.

TAFRO syndrome is an inflammatory disorder of unknown etiology characterized by thrombocytopenia, anasarca, fever, reticulin fibrosis, renal insufficiency, and organomegaly. Despite great advancements in research on the TAFRO syndrome in the last decade, its diagnosis and treatment are still challenging for most clinicians because of its rarity and severity. Since the initial proposal of the TAFRO syndrome as a distinct disease entity in 2010, two independent diagnostic criteria have been developed. Although these are different in the concept of whether TAFRO syndrome is a subtype of idiopathic multicentric Castleman disease or not, they are similar except for the magnitude of lymph node histopathology. Because there have been no specific biomarkers, numerous diseases must be ruled out before the diagnosis of TAFRO syndrome is made. The standard of care has not been fully established, but interleukin-6 blockade therapy with siltuximab or tocilizumab and anti-inflammatory therapy with high-dose corticosteroids are the most commonly applied for the treatment of TAFRO syndrome. The other immune suppressive agents or combination cytotoxic chemotherapies are considered for patients who do not respond to the initial treatment. Whereas glowing awareness of this disease improves the clinical outcomes of patients with TAFRO syndrome, further worldwide collaborations are warranted.

OBJECTIVE: To systematically evaluate the efficacy of subcutaneous tocilizumab in the treatment of patients with severe COVID-19 and provide evidence for the rational use of subcutaneous tocilizumab in patients with severe COVID-19.
METHODS: This meta-analysis was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. We searched the Cochrane Library, PubMed, Embase, CNKI, SinoMed, and Wanfang Medical Network electronic databases up to 11 January 2023 to identify relevant studies. To obtain the most recent clinical studies of subcutaneous injection of tocilizumab for the treatment of patients with severe COVID-19, we also searched the preprint platforms medRxiv and ChinaXiv. Furthermore, we searched ClinicalTrials.gov for relevant unpublished studies. The studies were screened based on the PICOS principle. The included studies were classified and evaluated for quality based on research type. The RevMan 5.3 software was used to conduct the meta-analysis, and a descriptive analysis was performed to examine relevant outcome indicators.
RESULTS: Five observational studies were obtained, involving a total of 498 patients (240 patients in the subcutaneous injection group and 258 patients in the intravenous injection group). All of the studies were of the highest quality. The meta-analysis of the included studies revealed that the mortality rate of patients who received subcutaneous tocilizumab to treat COVID-19 was not significantly higher than that of the intravenous injection group [23.3% (45/193) vs. 18.4% (39/212), RD = 0.06, 95% CI = - 0.01 ~ 0.13, P = 0.11]. Furthermore, there was no significant difference in the proportion of patients requiring mechanical ventilation between the two groups [24.5% (35/143) vs. 22% (35/159), RD = 0.03, 95% CI = - 0.07 ~ 0.12, P = 0.56].
CONCLUSIONS: The meta-analyses do not provide evidence that subcutaneous and intravenous tocilizumab formulations for the treatment of severe COVID-19 infection differ regarding their effectiveness. Considering that the meta-analyses cannot replace an appropriately powered non-inferiority study, subcutaneous formulations still need to be used with caution and only when intravenous formulations are in short supply. At present, there is a lack of randomized controlled trials of subcutaneous injection of tocilizumab for the treatment of severe COVID-19, and more clinical research should be conducted.

OBJECTIVE: To briefly review the latest updates in management in giant cell arteritis, an autoimmune vasculitis affecting the medium to large vessels.
RESULTS: Here, we review the known and newer trends in management of giant cell arteritis. While high dose glucocorticoids remain the mainstay of therapy, immunosuppressive medications are increasingly utilized to reduce the burden and risk of long-term glucocorticoid use. Published guidelines by the American College of Rheumatology (ACR) and European League Against Rheumatism (EULAR) suggest early use of steroid-sparing immunosuppressive medications in patients with recently diagnosed or relapsing giant cell arteritis. Immunosuppressive medications include oral small molecules such as methotrexate and leflunomide and biologics, including the recently Federal Drug Administration (FDA) approved tocilizumab. Glucocorticoids remain the cornerstone of management for newly diagnosed disease but with the increasing use of medications such as IL-6 inhibitors, patients are decreasing steroid use within weeks, thereby limiting risks associated with long-term steroid use.

OBJECTIVE: Aortitis in Giant Cell Arteritis (GCA-aortitis) is a frequent complication that may lead to aneurysms. Tocilizumab (TCZ) was approved in GCA, but the efficacy in GCA-aortitis and aneurysms has not been analyzed to date. Our aim was to assess the effectiveness and safety of TCZ in a wide series of GCA-aortitis and aneurysms.
METHODS: Multicentre observational study with GCA-aortitis treated with TCZ. GCA was diagnosed by: a) ACR criteria, b) temporal artery biopsy, and/or c) imaging techniques. Aortitis was diagnosed mainly by PET/CT. Main outcomes were EULAR and imaging remission. Others were clinical remission, analytical normalization, corticosteroid-sparing effect, and the prevention and improvement of aneurysms.
RESULTS: 196 patients with GCA-aortitis treated with TCZ. After 6 months, 72.2% reached EULAR remission but only 12% an imaging remission; increasing up-to 81.4% and 31.8%, respectively, at 24 months. A rapid clinical remission, ESR and CRP normalization was observed in 47.4%, 84.3% and 55.6%, at 1 month, increasing to 89.6%, 85.3% and 80.3% at 24 months, respectively. Aneurysms were present in 10 (5%) patients. Five of them required early surgery, while 3 others enlarged. No patient on TCZ therapy developed aneurysms during follow-up.
CONCLUSIONS: In patients with GCA-aortitis treated with TCZ, a rapid and maintained clinical and analytical improvement was observed. However, there was an uncoupling between clinical and EULAR remission with imaging remission.

There is growing interest in evaluating the safety and therapeutic potential of existing treatments such as tocilizumab (TCZ), an IL-6 receptor antagonist used to treat inflammatory diseases. However, there have been reports of increased inflammation in patients with HTLV-1 uveitis after TCZ treatment, and its ocular safety in the HTLV-1 infected state remains unknown. This study focused on assessing the impact of TCZ on HTLV-1-infected ocular cells using an in vitro model in which retinal pigment epithelial cells were cocultured with irradiated HTLV-1-infected T-cell lines. TCZ did not significantly affect cellular viability, inflammatory markers, or HTLV-1 proviral loads at various concentrations (25/50/100 µg/ml), indicating no increased risk of HTLV-1 viral infection and no exacerbation of the inflammatory aspects of HTLV-1 infection in the ocular cells. These promising results support the potential of TCZ as a safe treatment option for HTLV-1-infected patients, particularly those with eye infections.

UNASSIGNED: This study compared the pharmacokinetics (PK), immunogenicity, and safety of candidate tocilizumab biosimilar, CT-P47, administered via auto-injector (CT-P47 AI) or pre-filled syringe (CT-P47 PFS), in healthy Asian adults.
UNASSIGNED: In this phase I, multicenter, open-label study, participants were randomized 1:1 to receive a single 162 mg/0.9 mL dose of CT-P47 via AI or PFS. Primary endpoints were area under the concentration - time curve from time zero to infinity (AUC0-inf) and maximum serum concentration (Cmax). PK equivalence was determined if 90% confidence intervals (CIs) for the ratios of geometric least-squares means (gLSMs) were within the predefined 80-125% equivalence margin. Secondary PK parameters, immunogenicity, and safety outcomes were also assessed.
UNASSIGNED: Of 314 participants randomized (155 CT-P47 AI; 159 CT-P47 PFS), 310 received the study drug (153 CT-P47 AI; 157 CT-P47 PFS). Primary and secondary PK results, immunogenicity and safety were similar between groups. Ninety percent CIs for the ratio of gLSMs were within the predefined equivalence margin for AUC0-inf (85.87-102.94) and Cmax (82.98-98.16).
UNASSIGNED: PK equivalence between CT-P47 AI and CT-P47 PFS was demonstrated in healthy Asian adults, with comparable immunogenicity and safety between the two devices.
UNASSIGNED: ClinicalTrials.gov: NCT05617183.
Tocilizumab is a biologic medicine used to treat inflammatory diseases, such as rheumatoid arthritis. A biosimilar is a drug that is an almost identical copy of an approved original (‘reference’) biologic medicine; it has identical efficacy and safety to the original medicine but is typically less expensive. CT‑P47 is in development as a possible tocilizumab biosimilar.Some patients prefer injections using an auto-injector (AI) rather than a pre-filled syringe (PFS), for reasons including ease of use and convenience. With an AI, medicine is delivered automatically by firmly pressing the device against the skin, whereas, with a PFS, a needle is inserted into the skin and medicine delivered by depressing the plunger. The injection of CT‑P47 using a PFS has shown comparable pharmacokinetics (i.e., the uptake, metabolism and excretion of the drug by the body) and safety to tocilizumab. Therefore, if the pharmacokinetics and safety of CT‑P47 administered via AI and PFS were shown to be similar, this might expand the choice of administration devices available to patients.In this study, 310 healthy adults received a single injection of CT‑P47 via AI or PFS. Blood samples were taken over 43 days to analyze pharmacokinetics. The uptake, metabolism and elimination of CT‑P47 by the body was similar when administered by each device, suggesting that CT‑P47 can be administered by either AI or PFS.

OBJECTIVE: To evaluate the effect of interleukin-6 (IL-6) inhibitor (tocilizumab) on bacterial infection-associated bone resorption around implants during osseointegration in rabbits.
METHODS: At total of 24 male, 9-monthold New Zealand white rabbits were included, and their two mandibular anterior teeth were extracted. Three months after extraction, 24 one-piece Dentium implants (Ø 2.5 mm, intraosseous length of 12 mm) were inserted in the anterior mandible, and the rabbits were divided into four groups (n = 6 per group). Different treatment methods were used in each group: blank control group (BC); only silk ligation (negative control [NC]); silk ligation and injection with minocycline hydrochloride ointment (positive control [PC]); and silk ligation and injection with tocilizumab at 8 mg/kg via the auricle vein (experimental [EP]). Eight weeks later, the animals were sacrificed, and samples were collected and then analyzed using microcomputed tomography (microCT) scanning, immunohistochemical analysis, and histologic analysis.
RESULTS: From the microCT measurement, the ratio of the bone volume to the total volume (BV/TV) in the EP group was 67.00% ± 2.72%, which was higher than that in the other three groups (58.85% ± 2.43% in the BC group, 55.72% ± 2.48% in the PC group, and 36.52% ± 3.02% in the NC group). From immunohistochemical analysis, the expression of IL-6 was found to be higher in the NC group than in the BC, PC, and EP groups, but there was no statistical difference between these three groups. Furthermore, the RANKL (receptor activator of nuclear factor-κB ligand) expression was the lowest in the EP group, followed by the BC group, the PC group, and the NC group, which had the highest expression; there was no difference between the NC and PC groups. Upon histologic analysis, significant new bone was found on the implant surfaces in the EP group, sparse and less new bone could be seen in the BC and PC groups, and the most serious bone resorption occurred in the NC group.
CONCLUSIONS: Tocilizumab, an inhibitor of IL-6, has a certain effect in preventing bone loss around implants caused by bacterial infection during the osseointegration period.

TAFRO syndrome is a rare systemic inflammatory disorder of unknown etiology characterized by thrombocytopenia, anasarca, fever, reticulin myelofibrosis, renal dysfunction, and organomegaly. The diagnosis of TAFRO syndrome can be challenging; however, prompt diagnosis is vital because TAFRO syndrome is a progressive and life-threatening disease. We have showcased five patients with TAFRO syndrome who had similar bone marrow (BM) findings that could be considered the findings that characterize TAFRO syndrome. All patients were treated with corticosteroids and tocilizumab; three of the five patients (60 %) responded positively to the treatment. The unique BM findings observed in this study were megakaryocytes with distinct multinuclei and three-dimensional and indistinct bizarre nuclei (\"dysmorphic megakaryocyte\"), similar to the megakaryocyte morphology observed in myeloproliferative neoplasms (MPNs). Notably, dysmorphic megakaryocytes were observed in all five cases, whereas only two of the five patients tested positive for reticulin myelofibrosis, and three of the five patients had megakaryocytic hyperplasia, which are considered typical findings of TAFRO syndrome. Thus, the BM findings of dysmorphic megakaryocytes could help in the correct and immediate diagnosis of TAFRO syndrome.