Inside Kyverna's Autoimmune CAR T Platform Beyond SPS

By Erin Harris, Editor-In-Chief, Cell & Gene
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When I interviewed Dr. Naji Gehchan, Kyverna Therapeutics’ chief medical and development officer, for Cell & Gene: The Podcast, we discussed the company’s effort to apply CAR T-cell therapy to severe autoimmune disease. We talked all about the company’s investigational CAR T, mivocabtagene autoleucel (miv-cel), its development in stiff person syndrome (SPS), and the possibility that deep B-cell depletion could enable durable, drug-free remission for patients with limited treatment options.

The company is now bringing that premise closer to a commercial test, as it has initiated a rolling BLA for miv-cel in SPS and submitted its CMC module, with completion of the overall filing expected in Q4 2026. If approved, miv-cel could become the first FDA-approved CAR T-cell therapy for an autoimmune disease.

Kyverna’s CEO Warner Biddle described a focused strategy that prioritizes neurologic autoimmune diseases with substantial unmet need, shared B-cell-driven biology, and treatment pathways capable of supporting cell therapy administration.

Making Autoimmune CAR T Its Own Discipline

According to Biddle, success in autoimmune CAR T requires more than applying oncology approaches to a new disease area. “It starts with selecting indications where the biology is well understood, the unmet need is high, and treatment centers can effectively support patients throughout the CAR T journey.”

Oncology CAR T development has historically focused on aggressive malignancies, heavily pretreated patient populations, response rates, and the operational demands of delivering a personalized therapy. Autoimmune disease presents a different set of questions. Developers need to establish which conditions are most clearly driven by pathogenic B cells, how long B-cell depletion must persist, which endpoints best capture meaningful functional change, and whether a one-time intervention can reduce or eliminate chronic immunosuppression.

Kyverna is applying that framework across SPS, generalized myasthenia gravis (gMG), and progressive multiple sclerosis (PMS).

“Clinical experience to date with miv-cel suggests the potential for a paradigm shift in autoimmune disease treatment with unprecedented clinical outcomes, moving beyond symptom control to the possibility of eliminating chronic immunosuppressive therapies,” Biddle said.

That proposition is particularly significant for patients who may cycle through immunomodulators, biologics, plasma exchange, steroids, and other interventions without achieving sustained disease control or functional improvement. The test will be whether CAR T can deliver reproducible, durable outcomes with a manageable safety profile and a treatment model that patients and healthcare systems can realistically support.

CMC Becomes a Commercial Strategy

Kyverna’s decision to initiate its rolling BLA with the CMC module underscores the role manufacturing readiness will play in autoimmune CAR T commercialization. The company submitted the CMC module in July and says its manufacturing process has supported treatment of more than 100 patients across its clinical programs.

“CMC is often one of the most complex aspects of development, requiring rigorous process validation, quality controls, supply chain reliability, and consistent product delivery at scale,” said Biddle. “By prioritizing CMC early, we aimed to establish a strong foundation for the overall regulatory package.”

The broader lesson for autoimmune CAR T is that clinical results alone will not determine commercial success. Developers will also need validated manufacturing processes, reliable supply chains, treatment-center engagement, reimbursement planning, and a strategy for patient access.

Regulatory Momentum in PMS

Kyverna’s RMAT designation for miv-cel in non-active secondary progressive multiple sclerosis (naSPMS) adds to the regulatory momentum behind the program. It is the third RMAT designation for miv-cel, following designations in SPS and gMG.

The FDA based the RMAT designation on data from investigator-initiated trials (IIT) at Stanford University and the University of California, San Francisco.. Updated data from the Stanford Phase 1 IIT showed that five of six patients with available data had improvement in Expanded Disability Status Scale (EDSS) scores, while the remaining patient was stable at last follow-up. All patients remained off other immunomodulatory therapies.

EDSS is a widely used measure of disability in MS. In progressive disease, where slowing decline is often a central treatment objective, evidence of improvement warrants attention. Still, these are early IIT data, and larger controlled studies and longer follow-up will be needed to assess durability, safety, and which patient populations may be most likely to benefit.

Kyverna expects to share additional Phase 1 IIT data in Q4 2026 and provide an update on its PMS development strategy by early 2027.

Building a Neuroimmunology Platform

Biddle described miv-cel as a platform rather than a set of disconnected disease programs. The strategy rests on the premise that SPS, gMG, and PMS share enough B-cell-driven biology to support common clinical, operational, manufacturing, and treatment-center infrastructure. “Miv-cel is a technology platform that enables each indication to build on the next, supporting our highly synergistic and scalable neuroimmunology franchise,” he said.

That could provide an important advantage as autoimmune CAR T moves toward commercialization. A developer that can carry manufacturing capabilities, clinical operations, treatment-center relationships, reimbursement preparation, and commercial infrastructure across multiple indications may be able to scale more efficiently than one building separate systems for each disease.

Biddle also pushed back on the assumption that autoimmune CAR T will encounter precisely the same barriers as the first oncology CAR T launches. “The reality is that the field has matured significantly, with more established manufacturing processes, expanded capacity, and broader treatment-center infrastructure,” he said.

Those advances do not eliminate the complexity of autologous cell therapy. They do, however, give autoimmune CAR T developers a more established foundation.

Kyverna must next show that its clinical data, manufacturing readiness, and focused neuroimmunology strategy can be translated into a viable one-time treatment option for patients with serious autoimmune disease. If miv-cel reaches the market, the significance will extend beyond a single SPS approval. It could provide an early test of whether autoimmune CAR T can evolve into a scalable therapeutic platform across multiple diseases.