As Kyverna Therapeutics advances toward potential market approval for its cell therapy targeting severe autoimmune conditions, major pharmaceutical developers including Novartis and Bristol Myers Squibb have frozen clinical studies following severe patient safety setbacks. These competing trials were halted after investigators observed fatal immune-related toxicities and inflammatory events in nonfatal chronic diseases.
CAR T Therapy Targets Autoimmune Disorders
- What is CAR T Therapy? Chimeric antigen receptor T-cell therapy involves extracting a patient’s immune cells, genetically reprogramming them in a laboratory to hunt down specific cellular targets, and infusing them back into the body.
- The Shift to Autoimmunity: While originally engineered to treat blood cancers by destroying malignant cells, researchers adapted the platform to wipe out malfunctioning B cells responsible for driving chronic autoimmune disorders.
- The Safety Risk: Because autoimmune diseases are generally nonfatal unlike advanced cancers, the margin for adverse events—such as severe immune system overactivation—is remarkably narrow.
Safety Setbacks and Trial Suspensions at Novartis and Bristol Myers Squibb
The clinical momentum behind cellular immunotherapy in immunology hit substantial roadblocks as leading pharmaceutical companies reported critical safety events. Novartis confirmed to BioSpace that it paused several clinical evaluations of its CAR T candidate rapcabtagene autoleucel, or rap-cel, in autoimmune indications. The regulatory and clinical pause followed the deaths of three trial participants who developed immune effector cell-associated hemophagocytic syndrome after receiving the infusion.
Bristol Myers Squibb followed a similar trajectory, voluntarily freezing its own autoimmune trials for zolacabtagene autoleucel, or zola-cel. According to notes from William Blair analysts cited by BioSpace, the pharmaceutical company stepped back after observing transient and reversible inflammatory events during administration. These developments triggered immediate caution across financial and clinical sectors regarding the risk-benefit calculations of deploying potent cancer-fighting therapeutics into chronic, nonfatal disease populations.
“We believe that the emergence of serious immune-related toxicities—including three patient deaths for rapca-cel (NVS)—adds considerable uncertainty to the auto-CAR-T use case in [autoimmune disease],” Leerink Partners wrote in a note to investors on September 1, 2026. Sanjeev Luther, CEO of Ernexa Therapeutics, noted to BioSpace that CAR T therapies were never originally designed for the autoimmune space. “What you look for in oncology in terms of tox versus efficacy, that equation is so different than what you would see in autoimmune diseases,” Luther stated, adding that while autoimmune conditions severely diminish quality of life, patients do not typically face immediate mortality.
Kyverna Therapeutics Advances Miv-cel Amid Persistent Immune Risks
Despite industry-wide turbulence, Kyverna Therapeutics continues progressing toward regulatory milestones with its candidate mivocabtagene autoleucel, or miv-cel. The investigational cell therapy has demonstrated improved mobility and reduced disability scores in clinical evaluations involving patients with stiff person syndrome, a rare and progressive neurologic autoimmune disorder.
Kyverna reported a solid safety profile for miv-cel thus far, positioning the company at the forefront of the emerging market. Warner Biddle, CEO of Kyverna, emphasized that the underlying disease burden in conditions like stiff person syndrome remains severely underappreciated by clinical developers. Over 80% of affected individuals eventually require ambulatory assistance such as a walker or wheelchair, and fewer than 20% maintain employment four years post-diagnosis, according to Biddle’s remarks to BioSpace.
The fundamental biological overlap between oncology and immunology was underscored by Will Ho, founder and CEO of IN8bio. “I think oncology and autoimmune are almost like two sides of the same coin,” Ho told BioSpace. “If I have an overactive immune system, I’m going to get autoimmune disease. But if I repress the immune system enough, I’m going to get immune escape of transformed cells, and I get a cancer.” Kate Rochlin, president and COO of IN8bio, added that the physiological risk of cytokine secretion and immune overactivation has always accompanied these platforms, forcing a recalibration as therapies cross into nonfatal indications.
| Candidate Drug | Developer | Target Indication | Clinical Status (as of Fall 2026) |
|---|---|---|---|
| Rapcabtagene autoleucel (rap-cel) | Novartis | Autoimmune Diseases | Paused following three patient deaths from immune-related toxicities |
| Zolacabtagene autoleucel (zola-cel) | Bristol Myers Squibb | Autoimmune Diseases | Voluntarily frozen due to transient inflammatory events |
| Mivocabtagene autoleucel (miv-cel) | Kyverna Therapeutics | Stiff Person Syndrome | Progressing toward market approval with a reported solid safety profile |
Clinical Data Sparks Commercial Interest in Immunotherapy
Cellular immunotherapy captured widespread attention in late 2023 when clinical data presented by Georg Schett and colleagues at the American College of Rheumatology’s Convergence demonstrated sustained disease remission in eight systemic lupus erythematosus patients after up to two years of monitoring. Those findings were subsequently published in The New England Journal of Medicine in February 2024, showing functional improvements across cohorts suffering from idiopathic inflammatory myositis and systemic sclerosis.
That clinical breakthrough inspired a rapid surge of commercial interest. “To us, it seemed like every single one of our CAR T competitors and colleagues became an autoimmune company overnight,” Will Ho told BioSpace. From a market perspective, the transition represents an exponential expansion in patient volume. While oncology indications generally target tens of thousands of cancer patients, successful autoimmune deployment opens addressable markets encompassing millions of chronic sufferers worldwide.
References
- Schett, G., et al. (2024). CAR T Cell Therapy in Systemic Lupus Erythematosus. The New England Journal of Medicine.
- American College of Rheumatology. (2023). Convergence Clinical Data Presentations on B Cell–Targeting Immunotherapies.
- BioSpace. (2026). Weighing the risks of CAR T in autoimmune disease as Kyverna nears market.
