Systemic Lupus Erythematosus

Managing risk factors & New drugs in clinical trials

Introduction & Scope

Systemic Lupus Erythematosus (SLE) is a chronic, multisystem autoimmune disease in which the immune system mistakenly attacks healthy tissues, leading to widespread inflammation and progressive organ damage. Although the precise cause of SLE remains incompletely understood, its pathogenesis is widely recognized as multifactorial, involving a complex interplay of genetic susceptibility, hormonal influences, and environmental triggers.

SLE disproportionately affects women, with a female-to-male ratio of approximately 9:1, particularly during the reproductive years. Disease onset most commonly occurs between 15 and 45 years of age. The prevalence of SLE also varies significantly by ethnicity, with higher rates observed among African American, Hispanic, and Asian populations, underscoring the role of genetic and sociodemographic factors in disease risk and severity.

From an epidemiological perspective, SLE affects an estimated 20 to 150 individuals per 100,000 worldwide, with considerable geographic and population-based variability. Advances in diagnosis and treatment have markedly improved survival over recent decades. Nevertheless, mortality among individuals with SLE remains two- to three-fold higher than in the general population, largely driven by complications such as cardiovascular disease, severe infections, and lupus nephritis.

The clinical and societal burden of systemic lupus erythematosus is substantial. Patients often contend with chronic and fluctuating symptoms, including fatigue, inflammatory arthritis, cutaneous manifestations, and organ involvement, that significantly impair quality of life. For healthcare providers, SLE presents ongoing challenges due to its heterogeneous clinical presentation, unpredictable disease course, and the need for long-term, multidisciplinary management. In parallel, the economic impact of lupus is considerable, encompassing both direct healthcare costs (hospitalizations, medications, specialist care) and indirect costs related to work disability, reduced productivity, and long-term morbidity.

A comprehensive review of all aspects of SLE is beyond the scope of this article. Readers seeking in-depth background information may consult authoritative resources such as:

• Centers for Disease Control and Prevention (CDC): Lupus 
• National Resource Center on Lupus
• The Lupus Initiative
• Lupus Foundation of America
• Medscape: Systemic Lupus Erythematosus (SLE)

In this article, we focus on two interrelated and clinically actionable areas: the management of modifiable risk factors in SLE and emerging therapeutic strategies currently under investigation in clinical trials. Together, these perspectives highlight evolving opportunities to reduce disease burden, prevent long-term complications, and improve outcomes for individuals living with systemic lupus erythematosus.

Managing Risk Factors in Systemic Lupus Erythematosus

​Because systemic lupus erythematosus (SLE) arises from a complex interaction of genetic susceptibility, infections, immune dysregulation, and environmental exposures, individuals at increased risk may benefit from proactive risk assessment and preventive strategies. Although no single intervention can prevent SLE, accumulating evidence suggests that early surveillance and modification of known risk factors may reduce disease onset, severity, or long-term complications.

Genetic Susceptibility

The contribution of genetics to SLE risk has been recognized long before the advent of modern genotyping and genome-wide association studies. SLE is characterized by high heritability, estimated at approximately 66%. Twin studies demonstrate concordance rates of 24-56% in monozygotic twins, compared with 2-5% in dizygotic twins, while sibling recurrence risk ratios range from 8 to 29, underscoring the strong genetic component of the disease [1].

From a clinical perspective, the presence of a first-degree relative with lupus should prompt heightened awareness of potential predisposition, with risk increasing proportionally to genetic relatedness. Predisposed individuals may benefit from working with a primary care physician to establish a structured surveillance program, particularly during high-risk life stages such as adolescence, pregnancy, or periods of hormonal change. Advances in genotyping now allow identification of major SLE risk alleles and the calculation of polygenic risk scores, which may become increasingly useful for personalized risk stratification. In this context, collaboration between a genetic counselor and primary care provider can help translate genomic insights into practical monitoring strategies.

Viral Infections and Immune Triggers

The association between viral infections and SLE is well documented. Among the most consistently implicated pathogens are Epstein-Barr virus (EBV), cytomegalovirus (CMV), parvovirus B19, and endogenous or exogenous retroviruses, which may trigger autoimmunity through molecular mimicry or immune system activation [2]. Additional case reports and observational studies have linked infections such as dengue virus, hepatitis C, and SARS-CoV-2 (COVID-19) to lupus onset or flares [3-5].

For individuals at increased risk of SLE, routine monitoring for viral infections, adherence to vaccination guidelines, and early treatment of infections are important preventive measures. Immunization strategies should follow recommendations from the Centers for Disease Control and Prevention (CDC) and the American College of Rheumatology (ACR), with individualized adjustments based on immune status and treatment exposure.

Gut Microbiota and Immune Dysregulation

An expanding body of research has identified significant gut microbiome dysbiosis in patients with SLE compared with healthy controls [6]. Despite geographic variation reflecting diet and lifestyle, two consistent features emerge across studies: reduced microbial diversity and a low Firmicutes-to-Bacteroidetes (F:B) ratio. These changes promote disruption of the intestinal barrier ("leaky gut"), facilitating translocation of commensal and pathobiont species—such as Lachnospiraceae, Enterococcus gallinarum, Ruminococcus gnavus, and Lactobacillus reuteri—into the lamina propria.

This microbial translocation can drive local inflammation, immune activation, and autoantibody production via antigen mimicry, linking gut dysbiosis directly to lupus pathogenesis. Given the limitations of current SLE treatments, microbiome-targeted interventions have attracted increasing interest. Dietary modification, probiotics, and fecal microbiota transplantation (FMT) are all under investigation, with early-phase clinical trials suggesting potential benefit [7]. At present, however, these approaches remain experimental and should only be pursued under strict medical supervision. Assessing the degree of dysbiosis in genetically predisposed individuals may eventually prove useful for risk assessment and early intervention, although clinical implementation is still evolving.

Environmental and Lifestyle Triggers

Understanding genetic and immunologic risk provides a framework for managing environmental triggers, which may influence both disease onset and progression. While the relative impact of individual triggers varies between patients, several exposures have been consistently associated with increased SLE risk.

Occupational and Environmental Chemical Exposure

Multiple studies implicate exposure to industrial and agricultural chemicals in lupus development, particularly among industrial and agricultural workers. Identified agents include silica and silicates, pesticides (notably polychlorinated biphenyls and dibenzofurans), industrial solvents, and heavy metals such as lead and mercury [8,9,12,13].

Smoking

The role of cigarette smoking in lupus has been debated for years; however, recent systematic reviews and meta-analyses indicate that smoking increases SLE risk, exacerbates disease activity, and may reduce treatment responsiveness [8-10,14]. Smoking cessation should therefore be considered a cornerstone of lupus risk reduction.

Ultraviolet (UV) and Sun Exposure

There is strong clinical evidence linking UV radiation, particularly UV-B exposure, to lupus onset and disease flares. Photosensitivity is a well-recognized feature of SLE pathogenesis, reinforcing the importance of sun avoidance strategies and photoprotection in at-risk individuals [8-11].

Medications and Drug-Induced Lupus (DIL)

Drug-induced lupus has been recognized since the mid-20th century and typically resolves after discontinuation of the offending agent [16,17]. Analysis of the WHO pharmacovigilance database identified over 100 medications associated with DIL, with procainamide, hydralazine, and several TNF-alpha inhibitors (infliximab, adalimumab, etanercept) showing the strongest associations [15,18].

Sex Hormone Therapy

Sex hormones represent a special category of risk-modifying medications. Large cohort studies demonstrate a dose-dependent increase in SLE risk among susceptible women initiating combined oral contraceptives [19]. Increased risk has also been reported in transgender women receiving feminizing hormone therapy, before and after sex reassignment surgery [20-24]. Notably, hormonal contraceptives generally do not worsen disease activity in women with stable SLE, except in those with moderate to high antiphospholipid antibody levels, where thrombotic risk is increased [9].

References
[1] Deng Y, Tsao BP. Genetic susceptibility to systemic lupus erythematosus in the genomic era. Nat Rev Rheumatol. 2010;6(12):683-692. doi: 10.1038/nrrheum.2010.176.
[2] Blank M, Schoenfeld Y & Perl A. Cross-talk of the environment with the host genome and the immune system through endogenous retroviruses in systemic lupus erythematosus. Lupus 2009; 18: 1136-1143.
[3] Rajadhyaksha A, Mehra S. Dengue fever evolving into systemic lupus erythematosus and lupus nephritis: a case report. Lupus. 2012;21: 999-1002. doi:10.1177/0961203312437807
[4] Sayiner ZA, Haque U, Malik MU, Gurakar A. Hepatitis C virus infection and its rheumatologic implications. Gastroenterol Hepatol (N Y). 2014;10: 287-93.
[5] Zamani, B., Moeini Taba, SM. & Shayestehpour, M. Systemic lupus erythematosus manifestation following COVID-19: a case report. J Med Case Reports. 2021;15,29. https://doi.org/10.1186/s13256-020-02582-8
[6] Toumi E, Mezouar S, Plauzolles A, et al. Gut microbiota in SLE: from animal models to clinical evidence and pharmacological perspectives. Lupus Science & Medicine. 2023;10: e000776.
doi: 10.1136/lupus-2022-000776
[7] Huang C and Yi P, Zhu M et al. Safety and efficacy of fecal microbiota transplantation for treatment of systemic lupus erythematosus: An EXPLORER trial. Journal of Autoimmunity. 2022; 130: 102844. doi.org/10.1016/j.jaut.2022.102844
[8] Refai RH, Hussein MF, Abdou MH & Abou‑Raya AN. Environmental risk factors of systemic lupus erythematosus: a case–control study. Nature Scientific Reports. 2023; 13:10219. https://doi.org/10.1038/s41598-023-36901-y
[9] Cardelli C, Zucchi D, Elefante E, Signorini V, Menchini M, Stagnaro C, Mosca M & Tani C. Environment and systemic lupus erythematosus. Clinical and Experimental Rheumatology. 2024; 42: 1104-1114.
[10] Bengtsson AA, Rylander L, Hagmar L, Nivet O & Sturfelt G. Risk factors for developing systemic lupus erythromatosus: a case-controlled study in southern Sweden. Rheumatology 2002; 41: 563-571.
[11] Kuhn A, Wenzel J & Weyd H. Photosensitivity, Apoptosis, and Cytokines in the Pathogenesis of Lupus Erythematosus: a Critical Review. Clinic Rev Allerg Immunol. 2014; 47:148–162. https://doi.org/10.1007/s12016-013-8403-x
[12] Tsai P-C, Ko Y-C, Huang W, Liu H-S & Guo L. Increased liver and lupus mortalities in 24-year follow-up of the Taiwanese people highly exposed to polychlorinated biphenyls and dibenzofurans. Science of the Total Environment. 2007; 374: 216–222.
[13] Parks CG & De Roos AJ. Pesticides, chemical and industrial exposures in relation to systemic lupus erythematosus. Lupus. 2014; 23: 527–536. doi:10.1177/0961203313511680.
[14] Mak A & Tay SH. Environmental Factors, Toxicants and Systemic Lupus Erythematosus. Int. J. Mol. Sci. 2014; 15: 16043-16056. https://doi.org/10.3390/ijms150916043
[15] Arnaud L, Mertz P, Gavand P, et al. Drug-induced systemic lupus: revisiting the ever-changing spectrum of the disease using the WHO pharmacovigilance database. Annals of the Rheumatic Diseases. 2019;78:504-508.
[16] Hoffman BJ. Sensitivity to sulfadiazine resembling acute disseminated lupus erythematosus. Arch Dermatol Syphilol 1945; 51:190–192.
[17] Kaufman CL & Quiroz EH. Drug-Induced Lupus Erythematosus. Medscape. 2020; 1065086. https://emedicine.medscape.com/article/1065086-overview
[18] Arnaud L, Mertz P, Gavand PE et al. Drug-induced systemic lupus: revisiting the ever-changing spectrum of the disease using the WHO pharmacovigilance database. Ann Rheum Dis 2019; 78: 504-8. https:// doi.org/10.1136/annrheumdis-2018-214598
[19] Bernier MO, Mikaeloff Y, Hudson M et al. Combined oral contraceptive use and the risk of systemic lupus erythematosus. Arthritis Rheum. 2009; 61: 476-81. https://doi.org/10.1002/art.24398
[20] Santos-Ocampo AS. New onset systemic lupus erythematosus in a transgender man: possible role of feminizing sex hormones. J Clin Rheumatol. 2007; 13: 29-30. https://doi. org/10.1097/01.rhu.0000256169.05087.ad
[21] Zandman-Goddard G, Solomon M, Barzilai A et al.: Lupus erythematosus tu midus induced by sex reassignment surgery. J Rheumatol 2007; 34: 1938-40.
[22] Chan KL, Mok CC: Development of sys temic lupus erythematosus in a male-to-fe male transsexual: the role of sex hormones revisited. Lupus 2013; 22: 1399-402. https://doi.org/10.1177/0961203313500550
[23] Pontes LT, Camilo DT, De Bortoli MR et al.: New-onset lupus nephritis after male to-female sex reassignment surgery. Lupus 2018; 27: 2166-69. https://doi.org/10.1177/0961203318800571
[24] Hill BG, Hodge B, Misischia R: Lupus nephritis in a transgender woman on cross sex hormone therapy: a case for the role of oestrogen in systemic lupus erythematosus. Lupus 2020; 29: 1807-10. https://doi.org/10.1177/0961203320946372

New Drugs in Clinical Trials for Systemic Lupus Erythematosus

​​The current standard of care for systemic lupus erythematosus (SLE) relies on a combination of pharmacologic classes, including antimalarials (hydroxychloroquine), nonsteroidal anti-inflammatory drugs (NSAIDs) (e.g., ibuprofen, naproxen, diclofenac), corticosteroids (prednisone, methylprednisolone), and immunosuppressive agents such as cyclophosphamide, methotrexate, azathioprine, mycophenolate mofetil, and intravenous immunoglobulin. More recently, targeted therapies have expanded treatment options, including B-cell-directed biologics (belimumab, rituximab), a type I interferon receptor antagonist (anifrolumab), and calcineurin inhibitors (tacrolimus and voclosporin).

Despite these advances, existing therapies remain suboptimal. Most primarily control symptoms rather than induce durable remission, and many are associated with significant long-term toxicities that negatively affect patients' quality of life. This unmet clinical need has driven an intense wave of innovation, reflected in the expanding pipeline of novel lupus therapies currently in clinical trials.
​
A review of ClinicalTrials.gov reveals five major therapeutic categories under active investigation: cell therapies, biologics, small molecules, natural products, and probiotics.

Cell-Based Therapies

Cell therapy represents one of the most promising and transformative approaches in SLE treatment. Interest surged following a landmark report by Mackensen and colleagues, who demonstrated remarkable clinical improvement in five patients with refractory SLE treated with anti-CD19 chimeric antigen receptor T (CAR-T) cells [1]. Since then, the clinical trial landscape has expanded rapidly.

Currently, more than 30 CAR-T trials are evaluating constructs targeting immune cell surface antigens such as CD19, CD20, CD3, and BCMA, either alone or in combination, with the goal of durably resetting dysregulated B- and T-cell responses. Among these, a notable innovation is the mRNA-based CAR-T platform (Descartes-08) developed by Cartesian Therapeutics (NCT06038474), which eliminates the need for ex vivo T-cell isolation and genetic modification, potentially improving safety, scalability, and patient convenience.

In parallel, CAR-NK cell therapies targeting CD19 are entering clinical evaluation, offering potential advantages in safety and off-the-shelf availability. Additional cell-based strategies include mesenchymal stem cell transplantation derived from umbilical cord blood or bone marrow, as well as trials exploring umbilical cord-derived NK cells. Collectively, these approaches aim to induce sustained immune reprogramming rather than transient immunosuppression.
​
The table shown below summarizes the cell therapy efforts.

Cell therapy	Number of clinical trials
	Enrollment completed (07/26/2024)	Enrolling
CAR-T therapy target
CD19	0	21
BCMA	0	3
CD19 & BCMA	0	8
CD19 & CD20	0	2
CD19 & CD3	0	1
BCMA & CD20	0	1
CAR-NK therapy target
CD19	0	2
Allogeneic umbilical cord blood NK therapy	0	1
Mesenchymal Stem Cell (MSC) therapy
Allogeneic umbilical cord blood derived	0	5
Allogeneic bone marrow derived	1	2
Autologous bone marrow derived	0	1

 

​​Biologic Therapies

Biologics remain a major pillar of innovation in lupus drug development. Current clinical trials encompass a diverse array of modalities, including monoclonal and bispecific antibodies, Fab fragments, diabodies, fusion proteins, and cytokine-based therapies. Beyond traditional B- and T-cell targets, these agents address a broader immunologic network implicated in SLE pathogenesis.

Key targets include plasmacytoid dendritic cell markers (BDCA2, ILT7), the CD40/CD40L costimulatory pathway, proinflammatory cytokines and their receptors, neonatal Fc receptor (FcRn), protein tyrosine phosphatase receptor type S, and components of the complement system. This diversification reflects growing recognition that lupus is driven by multiple converging immune pathways, necessitating more precise and adaptable therapeutic strategies.

​Clinical trials with different types of biologics are summarized in the table below.

Biologics	Number of clinical trials
	Enrollment completed (07/26/2024)	Enrolling
Monoclonal antibody target
BAFFR	1	5
BCMA	0	1
CD20	1	4
CD38	0	3
IFNAR-1	1	2
BDCA2	0	3
CD40 Ligand (CD40L)	0	1
CD40	1	0
IFN beta 1	0	1
IFN gamma	1	0
IL-6R	0	1
ILT7	0	1
PTPRS (Protein Tyrosine Phosphatase Receptor Type S)	0	1
Complement C5 protein	0	1
FcRn Ig binding site	1	0
Engineered bispecific antibody target
CD3 & CD19	0	1
CD20 & CD3	1	1
CD28 & ICOS	1	0
Fab fragment target
TNF	0	1
C1q	0	1
FcRn	0	1
Engineered bispecific diabody target
CD32B & CD79B	1	0
Engineered Fusion Proteins
TACI ECD fused to IgG1 Fc	0	8
IL-2-CD25(IL-2Ralpha) fusion	0	1
2 Tn3 CD40L binding domains-Human serum albumin fusion	0	1
Cytokines
Interleukin 2 (IL-2)	0	1
IL-2 mutein	1	2

 

Small-Molecule Therapies

Small-molecule drugs in development primarily target intracellular signaling pathways downstream of immune receptors. These include inhibitors of Bruton's tyrosine kinase (BTK) and mTOR, Janus kinases (JAKs) and tyrosine kinase 2 (TYK2) associated with cytokine signaling, and interleukin-1 receptor-associated kinases (IRAKs) involved in Toll-like receptor pathways.

Additional approaches aim to inhibit complement proteases (factors B and D), suppress immunoproteasome subunits (LMP2 and LMP7), or modulate immune cell trafficking through sphingosine-1-phosphate receptor-1 (S1PR1) to restore balance between regulatory T cells and proinflammatory Th17 cells. N-acetylcysteine, notable for its antioxidant properties and ability to inhibit mTOR signaling, is also under investigation as a potential adjunct therapy in SLE.

The table shown below summarizes all current small molecules trials.

Small Molecules target	Number of clinical trials
	Enrollment completed (07/26/2024)	Enrolling
TLR 7 and/or 8	0	3
Janus kinases (JAK 1 and/or 2)	3	5
Bruton tyrosine kinase (BTK)	1	1
Tyrosine kinase 2 (TYK-2)	0	2
IRAK-4	0	1
Mammalian Target of Rapamycin (mTOR)	0	1
KRAS G12C	0	1
Alternative Complement System (Factor B, D)	0	2
Immunoproteasome LMP 2&7	0	1
Sphingosine 1 Phosphate Receptor 1 (S1P1)	0	2
Lymphocyte glutathione depletion	0	1

 

​Natural Products

Among natural compounds, curcumin is currently being evaluated in a clinical trial for lupus nephritis (NCT05714670). Preclinical studies in lupus-prone mouse models demonstrated reduced neutrophil infiltration and renal inflammation following curcumin treatment. Mechanistically, these effects were linked to inhibition of the PI3K/AKT/NF-kB signaling pathway, which is activated by interleukin-8 and promotes neutrophil migration and tissue injury.

Probiotics

Reflecting growing interest in the gut-immune axis, a single clinical trial (NCT05433857) is investigating Lacteol Forte, a probiotic containing Lactobacillus acidophilus LB, in patients with systemic lupus erythematosus. This approach aligns with emerging evidence that modulation of gut microbiota may influence immune regulation and disease activity in SLE.

Outlook

Historically, the overall failure rate for novel therapies in autoimmune and inflammatory diseases has been high, approaching 85% according to prior analyses [2]. Even so, the breadth and mechanistic diversity of the current lupus pipeline provide cautious optimism that several new therapies may reach clinical practice in the coming years. Among these, CAR-T and CAR-NK cell therapies hold particular promise for achieving durable immune reset rather than incremental symptom control. Advances in mRNA-based delivery technologies further enhance the feasibility and patient acceptability of these next-generation treatments.
Together, these developments signal a pivotal shift in lupus therapeutics—from chronic disease management toward the possibility of deep, sustained remission driven by precision immunomodulation.

References
[1] Mackensen, A., Müller, F., Mougiakakos, D. et al. Anti-CD19 CAR T cell therapy for refractory systemic lupus erythematosus. Nat Med 28, 2124–2132 (2022). https://doi.org/10.1038/s41591-022-02017-5
[2] Chi Heem Wong, Kien Wei Siah, Andrew W Lo, Estimation of clinical trial success rates and related parameters. Biostatistics 20, 273–286 (2019). https://doi.org/10.1093/biostatistics/kxx069

Conclusion: From Risk Reduction to Immune Reset in Systemic Lupus Erythematosus

Systemic lupus erythematosus is no longer viewed solely as a disease to be managed reactively once organ damage has occurred. Growing insight into genetic susceptibility, environmental triggers, immune dysregulation, and lifestyle-related risk factors has reframed lupus as a condition in which earlier intervention and proactive risk management can meaningfully alter long-term outcomes. Optimizing sun protection, cardiovascular health, infection prevention, medication adherence, and stress and metabolic balance remains foundational to reducing disease flares and cumulative tissue injury.

At the same time, the expanding pipeline of novel lupus therapies signals a decisive shift beyond broad immunosuppression. Advances in biologics, small-molecule inhibitors, microbiome-based interventions, and especially cell-based therapies such as CAR-T and CAR-NK cells are targeting the core immune mechanisms that drive disease initiation and persistence. These approaches aim not merely to suppress inflammation, but to recalibrate or reset dysfunctional immune networks, raising the possibility of deeper and more durable remission.

The convergence of risk-factor modification with precision immunotherapy represents a new paradigm in lupus care. As biomarkers improve and clinical trials refine patient selection, treatment strategies are likely to become increasingly personalized, matching the right intervention to the right patient at the earliest possible stage of disease. While significant challenges remain, including safety, durability, and access, the trajectory of current research offers renewed hope that lupus management will evolve from lifelong symptom control toward prevention of irreversible damage and restoration of immune balance.
​
In this emerging landscape, empowering patients through education, early diagnosis, and proactive care will be as critical as therapeutic innovation itself. Together, these advances point toward a future in which systemic lupus erythematosus is detected earlier, treated more precisely, and lived with more fully.