Treatment Target Shows Promise in Systemic Lupus Erythematosus

The lupus low disease activity state (LLDAS) is a promising treatment target in systemic lupus erythematosus (SLE), according to new research.

Background
Successfully applied in rheumatoid arthritis as well as in non-rheumatic conditions, a treat-to-target approach aims to improve disease outcomes through the achievement of a pre-specified goal. An international task force suggested such a strategy for the treatment of SLE.¹ They recommended that the treatment target should be remission or-when that is unachievable-the lowest possible disease activity.

LLDAS is a composite definition of minimal acceptable disease activity proposed by the Asia-Pacific Lupus Collaboration (APLC). LLDAS is based on the following criteria:
1. SLE Disease Activity Index 2000 (SLEDAI-2K) ≤ 4, with no activity in major organ systems
2. No new lupus disease activity compared with the previous assessment
3. Safety of Estrogen in Lupus Erythematosus National Assessment (SELENA)-SLEDAI physician global assessment (PGA) ≤ 1
4. Current prednisolone (or equivalent) dose ≤ 7.5 mg daily
5. Well-tolerated standard maintenance doses of immunosuppressive drugs and approved biological agents

To be considered a valid treatment target, LLDAS should be protective against damage accrual in the early SLE stages. Piga and colleagues² at the University Clinic and AOU of Cagliari in Italy sought to determine the frequency of LLDAS achievement and its association with early damage accrual in a homogenous cohort of Caucasian patients with SLE prospectively assessed during the first 18 months of treatment after diagnosis.

The studyThis study primarily aimed to assess the frequency of LLDAS achievement and its association with early damage, with a secondary aim to identify the main reasons for failure to achieve LLDAS. The study cohort consisted of 107 patients from the Cagliari (Italy) SLE cohort between January 2006 and December 2016.

To assess LLDAS as a goal for initial treatment, the primary study endpoint was set at 6 months, with 18 months considered an appropriate time to evaluate the effect of maintenance treatment and early damage accrual. At each visit, disease activity was assessed using the SLEDAI-2K score and the PGA. At 18 months, damage accrual was assessed by the SDI and the possible attribution to corticosteroids was done according to a previous definition. Average daily dose of prednisolone (or equivalent) and ongoing use and new prescription of medications were assessed at every visit.

The findings
At the 6-month point, LLDAS had been achieved by 47 patients (43.9%). At 18 months, 48 patients (44.9%) were in LLDAS; 33 of them had achieved LLDAS at 6 months and were still in this condition and 15 had reached LLDAS for the first time. Of the 59 patients who were not in LLDAS at 18 months, 45 had never been in LLDAS and 14 had been in LLDAS at 6 months but no longer were at 18 months. Thus, despite a seemingly overall stable LLDAS rate, these results demonstrate the dynamic nature of this condition.

On univariate analysis, the following factors were significantly associated with failure to achieve LLDAS at 6 months: renal involvement, higher SLEDAI-2K score, positive (> 10 UL/mL) anti-dsDNA antibodies, lower serum C3 and C4 values, and higher prednisolone dose and immunosuppressant drug use. On multivariate analysis, renal involvement and C4 levels were confirmed to be associated with failure to achieve LLDAS.

Implications for physicians
The limitations of this study are the relatively small sample size, which may have hampered study results, and the retrospective design, which prevented researchers from testing LLDAS criterion validity by comparing it with other treatment targets such as the SLE Responder Index. Nevertheless, by enrolling consecutively diagnosed patients at the time of treatment initiation and following them prospectively, the researchers were able to provide novel data on LLDAS as a potential treatment target.

In this study, the most frequent reason for failure to achieve LLDAS 6 months after therapy initiation was daily prednisolone dosage > 7.5 mg. Damage was definitely attributable to steroid use in 40% of cases in this cohort. However, supported by this data and literature evidence on damage development, the researchers consider 7.5 mg/d an acceptable cutoff to define low disease activity during initial treatment. Still, they recommend a lower cutoff should be targeted to minimize risk of steroid-related damage during maintenance therapy in patients with SLE.

In this cohort, patients with renal involvement and serological disorders had the lowest remission rate, and renal involvement at baseline was the most important factor associated with failure to achieve LLDAS. “LLDAS is a promising treatment target in SLE, being attainable and negatively associated with damage accrual in the early stages of the disease,” the researchers write. “However, it seems to poorly fit with the heterogeneity of clinical presentation in patients with SLE, mostly in those with renal involvement,” they conclude.

References:

1. van Vollenhoven R, Voskuyl A, Bertsias G, et al. Treat-to-target in systemic lupus erythematosus: recommendations from an international task force. Ann Rheum Dis. 2014;73:958-967.

2. Piga M, Floris A, Cappellazzo G, et al. Failure to achieve lupus low disease activity state (LLDAS) six months after diagnosis is associated with early damage accrual in Caucasian patients with systemic lupus erythematosus. Arthritis Res Ther. 2017;19:247. doi: 10.1186/s13075-017-1451-5.