Cabaletta Bio signs 10-year cell therapy supply deal with Cellares

Cabaletta Bio has entered a ten-year commercial supply agreement with Cellares, the South San Francisco-based cell therapy manufacturer, to produce rese-cel (resecabtagene autoleucel) at industrial scale pending FDA approval. The deal, announced on 28 April 2026, covers supply of the autologous CAR T candidate using Cellares' Cell Shuttle automated manufacturing platform and, in time, its Cell Q quality-control system.

The two companies have worked together since 2023 to automate rese-cel's production process. Under the new commercial agreement, Cabaletta secures the ability to manufacture thousands of batches per year over the contract term with what both parties describe as minimal capital investment — claiming a per-batch cost among the lowest in the industry for autologous cell therapy. No precise cost figure was disclosed.

Scale ambition in a demanding indication

The emphasis on throughput reflects a genuine structural challenge facing CAR T in autoimmune disease. Oncology programmes typically target small, well-defined patient populations; autoimmune indications such as myositis, lupus, and the neurological conditions Cabaletta is pursuing span far larger cohorts. Steven Nichtberger, chief executive of Cabaletta, noted that industrialised automated manufacturing could support expansion to thousands of patients per year, a scale that conventional CDMO models — reliant on manual processes and significant facility investment — have struggled to reach economically.

Fabian Gerlinghaus, co-founder and chief executive of Cellares, framed the ambition explicitly: "Autoimmune diseases require a manufacturing infrastructure that operates at an order of magnitude greater scale than traditional oncology CAR T programmes. This 10-year commercial agreement with Cabaletta reflects confidence in the Cell Shuttle and Cell Q platforms."

Cabaletta intends to present initial translational data from the first two patients dosed with Cellares-manufactured rese-cel at the American Society of Gene and Cell Therapy (ASGCT) annual conference in May 2026. Longer-term clinical data from patients receiving Cellares-produced material are anticipated in the second half of 2026.

Regulatory and competitive context

Cabaletta is planning a Biologics Licence Application submission for rese-cel in myositis in 2027, which would represent one of the first CAR T therapies to seek FDA approval in an autoimmune rather than oncological indication. The regulatory pathway for autologous CAR T in autoimmune disease is still being shaped: the FDA has not yet approved any CAR T product for a non-oncology indication, though the agency's willingness to grant Advanced Manufacturing Technology designation to Cellares' Cell Shuttle platform suggests growing institutional familiarity with industrialised cell therapy production.

The broader competitive landscape is intensifying. Kyverna Therapeutics, Autolus, and several academic-spinout programmes in Europe are advancing CD19-directed CAR T approaches in autoimmune settings. Manufacturing economics are increasingly recognised as a differentiating factor: per-patient therapy costs for autologous CAR T have historically exceeded $400,000 in oncology, and commercial viability in autoimmune disease — where payers and health systems may be less accustomed to such price points — will depend heavily on the ability to compress production costs.

Cabaletta's stated strategy of layering multiple CDMO partners alongside Cellares is designed to provide supply-chain redundancy, a lesson drawn from oncology CAR T programmes where manufacturing failures have caused significant patient and commercial setbacks. The ten-year term of the Cellares agreement is notably longer than most CDMO contracts in cell therapy, signalling that both parties are treating this as a foundational rather than transitional arrangement. Investors will look to the ASGCT data readout in May as the first direct evidence of whether Cellares-manufactured rese-cel performs comparably to material produced under earlier manufacturing runs.