The next frontier: Can CAR T therapy become a one-time cure for autoimmune diseases?

The question of whether autoimmune diseases can one day be treated with a single therapy rather than a lifetime of medication is no longer theoretical. A new clinical and scientific narrative is emerging around the use of chimeric antigen receptor T cell (CAR T) therapy in autoimmune disorders, driven by companies such as Bristol Myers Squibb, which is advancing CD19-targeted CAR T cell therapy in systemic lupus erythematosus, systemic sclerosis and idiopathic inflammatory myopathies. These efforts represent a potential shift from chronic immunosuppression to immune reset, where the immune system is recalibrated rather than continually suppressed.

For decades, the standard of care in autoimmune disease has been built on cycles of immunosuppressants, biologics, corticosteroids and targeted inhibitors designed to dampen abnormal immune activity. These treatments can reduce symptoms and slow disease progression, but they require ongoing therapy, can weaken a patient’s immune system and may lose effectiveness over time. CAR T therapy introduces a different model altogether: extract a patient’s T cells, engineer them to eliminate disease-driving B cells, reinfuse them and allow the immune system to rebuild from a healthier baseline. The approach is inherently disruptive because it shifts the therapeutic goal from management to remission.

Why is CAR T therapy now being explored as a one-time treatment option in autoimmune diseases?

The rationale for applying CAR T therapy to autoimmune disease is rooted in a deeper understanding of the role that B cells play in many chronic inflammatory and autoimmune conditions. B cells produce antibodies, and in certain diseases such as systemic lupus erythematosus, systemic sclerosis and idiopathic inflammatory myopathies, the immune system mistakenly creates antibodies that attack healthy tissues. By selectively targeting B cells through engineered T cells, clinicians aim to eliminate the root cause of disease activity rather than merely blocking inflammatory pathways.

This approach has seen success in certain blood cancers, where CAR T therapies have demonstrated the ability to destroy malignant B cells and, in some cases, result in long-lasting remission. The hypothesis in autoimmune disease is similar: if the autoreactive B cell population can be removed and the immune system is allowed to repopulate under healthier conditions, the disease may remain inactive without ongoing therapy.

The concept is supported by early clinical results, where patients treated with CD19-directed CAR T therapies have shown evidence of sustained B cell depletion followed by the return of a naïve B cell population. This pattern suggests the immune system is reconstructing itself with less autoreactivity. The idea of immune reset is central to the therapeutic promise of this approach.

What early clinical signals suggest that durable remission may be achievable?

Across several early-stage trials, including Bristol Myers Squibb’s Breakfree-1 study, patients with severe autoimmune disease demonstrated meaningful clinical improvements after a single CAR T infusion. Patients with systemic lupus erythematosus who had failed multiple prior treatments showed sustained reductions in disease activity scores. Patients with systemic sclerosis, including those with involvement of the lungs, saw improvements in lung function and skin thickening, areas where therapeutic progress has historically been limited. In idiopathic inflammatory myopathies, patients experienced improvements in muscle strength and functional mobility.

These results, while early, suggest that CAR T therapy could deliver a level of disease modification that is not typically seen with conventional treatments. The key observation is that many patients remained off chronic immunosuppressive medications after receiving CAR T therapy. This challenges the traditional expectation that autoimmune disease requires lifelong treatment to avoid flare cycles.

The safety profile in autoimmune disease also appears manageable. While cytokine release syndrome and neurotoxicity are known risks associated with CAR T therapy, most events in autoimmune cohorts to date have been low-grade and resolved with standard care protocols. The safety-benefit profile will need to continue to be evaluated as studies progress into larger populations.

What challenges must be addressed before CAR T therapy can become a mainstream treatment option for autoimmune diseases?

There are several practical, clinical and economic challenges that must be overcome before CAR T therapy can become broadly accessible in autoimmune disease. The first is durability of response. It is not yet known how long the observed remission periods will last. Autoimmune diseases can evolve differently across patients, and long-term immune behavior after CAR T therapy remains an area of active investigation.

Manufacturing presents another challenge. CAR T therapy requires personalized production, including cell collection, genetic modification and controlled reinfusion. This process is complex, resource-intensive and, as currently structured, expensive. As a result, scale remains limited. Companies working in this field will need to optimize production, reduce turnaround time and explore allogeneic or “off-the-shelf” versions of CAR T to expand access.

Cost and reimbursement are also significant considerations. The upfront cost of a CAR T infusion is high when compared to individual doses of biologic drugs. However, if CAR T therapy eliminates the need for long-term medication use, the total cost over time may be lower. This raises questions about how payers structure coverage, how outcomes are measured and whether new value-based reimbursement models will be required.

Clinical integration is another hurdle. Rheumatology and immunology practices are not currently configured to deliver CAR T therapy, which is typically administered in specialized hospital centers. Successful use in autoimmune disease will require new care pathways and likely greater collaboration between rheumatologists and hematology or oncology departments.

How are pharmaceutical companies positioning themselves in this emerging therapeutic space?

Bristol Myers Squibb is not alone in pursuing CAR T therapy for autoimmune diseases, but it is among the most visible early movers. The company’s experience with approved CAR T therapies in oncology and its investment in next-generation manufacturing platforms provide strategic advantages in entering this field. Other biopharmaceutical companies, including emerging biotechnology firms specializing in immune tolerance and engineered cell therapy, are also advancing programs in lupus, myositis and other immune-mediated diseases.

The competitive landscape is still forming, but the momentum suggests that CAR T therapy may become a foundational modality in autoimmune drug development. Companies that historically depended on chronic biologic therapies may need to adapt their portfolios if immune reset therapies demonstrate durable benefit. The shift could resemble the transition from chemotherapy to immunotherapy in oncology, where companies that invested early secured long-term leadership positions.

What could the future of autoimmune disease treatment look like if one-time therapies prove successful?

If CAR T therapy continues to show durable benefit, the treatment paradigm for autoimmune disease could change substantially. Instead of managing disease activity indefinitely, clinicians could focus on achieving remission early in the disease course. Diseases that were once considered inevitably progressive may be approached with the goal of long-term stabilization or even functional recovery.

The implications extend beyond medicine into quality of life. Patients who currently rely on frequent injections, infusions or immunosuppressive medication regimens could potentially live without the ongoing burden of treatment and monitoring. This shift would redefine expectations for both patients and physicians.

The evolution of this field will depend on continued trial results, refinement of manufacturing and distribution models, reimbursement frameworks and collaboration across specialty areas. The next two to five years will be pivotal in determining how widely CAR T therapy is adopted in autoimmune disease.