2021EULAR Express: The efficacy and safety of belimumab in the treatment of lupus nephritis have been confirmed

On June 3, 2021, the second day of the EULAR meeting, the excitement is uninterrupted! For a long time, the treatment progress of systemic lupus erythematosus (SLE) and lupus nephritis (LN) has been the focus of academic conferences at home and abroad
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As the first biological agent approved for SLE indication, the efficacy and safety of belimumab (BEL) in the treatment of SLE have been confirmed
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So, for SLE patients with kidney involvement, especially lupus nephritis, is BEL equally safe and effective? The famous American rheumatologist R.
Furie and his collaborators conducted a 6-month open-label extension study based on the largest clinical study in the field of LN (BLISS-LN), and came to the following key conclusions: curative effect BEL treatment of LN can further improve renal remission, maintain low hormone usage, and improve the safety of biomarker levels in patients.
BEL treatment of LN patients has no new safety issues ●Research background and purpose BLISS- LN (NCT01639339) is the largest clinical study in the field of lupus nephritis (LN) so far.
The study confirmed that the combination of BEL (intravenous injection, IV) and ST will further improve the patient’s active LN compared with standard therapy (ST) Prognosis
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Based on the 2-year BLISS-LN study, R.
Furie et al.
carried out a 6-month open-label (OL) extended study to evaluate the additional efficacy and safety of BEL+ST combination therapy in the treatment of LN patients
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●Research methods During the OL extension study period, patients who have completed the BLISS-LN study who meet the criteria are included.
All patients receive BEL 10 mg/kg IV+ST treatment every month for 6 months
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Study endpoints include: safety; primary efficacy renal remission at 28 weeks (PERR: uPCR ≤0.
7, reduction of eGFR ≤20% of baseline or eGFR ≥60 ml/min/1.
73 m2); complete renal remission (CRR: uPCR <0.
5 , EGFR reduction ≤ 10% of baseline or eGFR ≥ 90 ml/min/1.
73 m2); the proportion of patients with SLEDAI score <4; hormone use; biomarker level
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●The results of the study included 257 patients in the BLISS-LN study, of which 255 patients received BEL treatment and were included in the safety analysis, and the efficacy of BEL was evaluated
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Among them, 123 patients received placebo treatment in the BLISS-LN study (BEL-naïve patients, including 1 patient who discontinued treatment due to intolerance), and 132 patients received BEL treatment (BEL-treated patients)
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In the end, 96.
5% of the patients completed the OL extension study, and 3.
5% of the patients discontinued the study early (mainly due to adverse events [AE], 2%)
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Efficacy results: BEL treatment of LN can further improve renal remission and improve the level of biomarkers in patients.
Renal remission: the proportion of patients with PERR and CRR increased compared with baseline, the proportion of patients who reached PERR and CRR at 28 weeks increased (Figure 1)
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It can be seen that BEL treatment will further improve the patient's renal remission, no matter whether it is a newly-treated BEL patient or a treated patient
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Figure 1 Renal remission in the two treatment groups at baseline and 28 weeks of OL
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Left: the proportion of PERR patients; right: the proportion of CRR patients.
BEL treatment can maintain low hormone usage and improve the patient's biomarker levels.
For patients with low baseline hormone usage (≤5 mg or ≤7.
5 mg), The hormone dosage was maintained until 28 weeks (Table 1)
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Compared with baseline, the autoantibody levels of patients in both treatment groups decreased at 28 weeks
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For patients with low baseline C3/C4 levels, the C3/C4 levels of the two groups increased from baseline at 28 weeks (Table 1)
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In addition, compared with the baseline, the proportion of patients with a SLEDAI score of <4 in the BEL treated group increased at 28 weeks; while the BEL-naïve group had a decrease in the proportion from the baseline (Table 1)
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Table 1 Renal remission, hormone dosage and biomarker level (N=254) at baseline and 28 weeks of OL.
Safety results: No new safety issues appeared in BEL treatment of LN patients.
In terms of safety, overall, 168/ 255 (65.
9%) patients had ≥1 adverse event (BEL initial treatment group: 76/123 [61.
8%]; BEL treated group: 92/132 [69.
7%])
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A total of 15/255 (5.
9%) patients had ≥1 serious adverse event.
The incidence of serious AEs in the BEL initial treatment group was 4.
1% (5/123), and the incidence of serious AEs in the BEL treated group was 7.
6% (10/132) ), 1 (0.
8%) deaths occurred in the BEL-initial treatment group
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●Research conclusions This study is currently the largest clinical study in the field of lupus nephritis (LN)-the open label extension study of BLISS-LN
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The study showed that during the 6-month study period, whether it was BEL-naïve patients or BEL-treated patients, the proportion of patients achieving PERR and CRR increased, and no new safety issues were found
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In addition, BEL treatment improved the levels of biomarkers in LN patients, especially in BEL-naïve patients
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In China, belyumumab has not been approved for lupus nephritis indications, but based on the announcement of more and more positive data, it is expected that the drug will bring good news to more LN patients in the near future
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Yimaitong compiled and compiled from: R.
Furie, et al.
EULAR 2021 Virtual Congress.
Abstract POS0689.