Cabaletta Bio (NASDAQ:CABA) executives told investors at the Guggenheim Emerging Outlook Biotech Summit 2026 that the company has initiated enrollment in what it described as its first pivotal program in myositis and expects the study could support a biologics license application (BLA) filing next year. Management also highlighted a newly cleared manufacturing pathway for its lead autologous CAR-T candidate, rese-cel, using a fully automated system developed with Cellares, which executives positioned as a major shift in scalability and expected margins for autologous cell therapy.
Pivotal myositis program: single-arm, 17 patients
Chief Medical Officer David Chang said Cabaletta’s pivotal myositis trial is a streamlined, single-arm study enrolling 17 patients. The company plans to compare response rates against a “background rate” derived from a registry database that Chang described as robust and high quality. He said the trial’s statistical assumptions are conservative, and that approximately five responders out of 17 patients would be needed to achieve statistical significance.
On regulatory risk, Chang said the company has already discussed the design with the FDA and received alignment supporting a single-arm approach. He added that the agency has shown a leaning toward accepting single-arm trials for CAR-T in autoimmune diseases, particularly when endpoints are objective and stringent. As described in the discussion, Cabaletta’s endpoint includes requirements related to being off immunomodulatory medications and on low-dose steroids, with Chang framing drug-free remission as an outcome the FDA has emphasized due to the chronic toxicity of long-term immunosuppression.
CEO Steven Nichtberger added that other companies are also using single-arm approaches in autoimmune CAR-T studies, citing Bristol Myers Squibb and Novartis. He noted Novartis had terminated a comparative study to initiate a single-arm study in the prior several months, arguing that broad rejection of single-arm designs would have implications across the autologous cell therapy field.
Outpatient optionality and safety profile discussion
Chang said the program includes optionality for outpatient treatment, though he noted the company had not discussed the outpatient/inpatient split of patients enrolled and dosed to date. He connected outpatient potential to the safety profile Cabaletta has reported with rese-cel, citing less than 30% incidence of grade 1 cytokine release syndrome (CRS) and more than 95% of patients having either no CRS or grade 1 CRS. Chang also said CRS tends to occur around day 7.
On neurotoxicity, Chang said the company previously reported two cases of ICANS and that it has been almost a year since the last ICANS event, with no additional ICANS reported beyond those two patients. He said Cabaletta subsequently instituted stricter criteria to avoid enrolling patients at higher risk.
Chief Commercial Officer Steve Gavel emphasized outpatient care as a key commercial differentiator, arguing that bed capacity constraints have become a limiting factor as more CAR-T programs expand. He cited his experience with CARVYKTI and said that, based on the most recent earnings call he reviewed, more than 50% of CARVYKTI patients are now treated in the outpatient setting, which he characterized as difficult given the underlying patient population. Gavel argued autoimmune patients are generally younger and more mobile, which he said should make outpatient administration more feasible.
Automated manufacturing with Cellares positioned as a “frame shift”
Nichtberger repeatedly pointed to the company’s manufacturing update as the most important recent development, saying Cabaletta’s IND amendment was cleared to allow an alternative manufacturing process for rese-cel using a fully automated system with “no human intervention.” He argued the approach would enable scalability to “5, 10, 15 thousand” patients with minimal capital investment and “very healthy margins,” calling it a fundamental shift for an autologous company.
He compared the impact of automated manufacturing to the Model T assembly line, contrasting traditional clean-room throughput constraints with what he described as the capacity of a “Cell Shuttle.” Nichtberger said the company expects to report the first administration of an autologous CAR-T product manufactured through that automated approach in the coming months and expects initial data from the Cellares partnership in “the next couple of months.”
On supply strategy, Nichtberger said Cabaletta intends to maintain at least two sources of manufactured product. He said the company currently works with Lonza and “what used to be WuXi,” and that Cellares could become one of the two sources if clinical data and a commercial agreement support the move forward.
Cost of goods and operational considerations
Discussing cost of goods (COGS), Nichtberger referenced industry-reported “price per run” figures in the range of $150,000 to $270,000, while stressing that investor models often fail to capture additional costs tied to unused manufacturing capacity. He said under traditional models, companies may pay for additional clean rooms and associated staffing before utilization ramps, potentially driving materially higher effective COGS if forecasts are off.
He also pointed to other potential cost drivers in oncology—such as patients dying during manufacturing—arguing these are less relevant in autoimmune disease, where patients generally do not die while waiting. Nichtberger further said autoimmune patients tend to have healthier T cells than heavily pretreated cancer patients, and noted Cabaletta has had one manufacturing failure across roughly 80 manufactured products, expecting low single-digit failures commercially.
No-preconditioning efforts and upcoming data
Management also highlighted efforts to administer rese-cel without preconditioning, which typically involves cyclophosphamide. Nichtberger said the company presented what it described as “very effective acute outcomes” in pemphigus vulgaris patients treated without preconditioning and is rapidly enrolling at both the initial dose and a higher dose. He said Cabaletta has initiated a no-preconditioning cohort in lupus as well, describing the approach as potentially meaningful for lupus patients who may prefer to avoid cyclophosphamide.
Chang said that in pemphigus vulgaris, at the 1 million cells/kg dose, the company observed responses including B-cell depletion, clinical response, and biomarker changes such as cytokine elevation and BAFF elevation, which he characterized as a marker for the magnitude of B-cell depletion. He said durability has been observed out to six months so far and that higher-dose exploration will be reported later this year. Chang added that the lupus no-preconditioning cohort has opened, and the company expects data this year. He said potential advantages could include avoidance of cytopenias; he noted that neutropenic fever combined with CRS-related fever can drive inpatient hospitalization, which could limit outpatient treatment.
Separately, Nichtberger said Cabaletta expects to report Phase 1/2 “complete data sets” in lupus, scleroderma, and myasthenia gravis in the first part of the year.
In closing remarks on financing, Nichtberger said the company has been spending roughly $10 million to $13 million per month and expects spending to increase somewhat as Cabaletta builds commercial capabilities.
About Cabaletta Bio (NASDAQ:CABA)
Cabaletta Bio is a clinical-stage biotechnology company pioneering chimeric autoantibody receptor T cell (CAAR-T) therapies for B cell–mediated autoimmune diseases. Its proprietary platform engineers patient-derived T cells to selectively target and eliminate pathogenic B cells that produce disease-driving autoantibodies, with the aim of preserving overall immune function and reducing off-target toxicity.
The company’s lead candidate, DSG3-CAART, is being evaluated in pemphigus vulgaris, a rare blistering disorder caused by autoantibodies against desmoglein 3.
