Shares of Cartesian Therapeutics Inc (NASDAQ:RNAC) climbed 14.5% in premarket trading Tuesday after the company disclosed a strategic licensing agreement with WestGene Biopharma Co., Ltd. The deal will pair WestGene’s targeted lipid nanoparticle delivery system with Cartesian’s mRNA payload derived from Descartes-08 to pursue in vivo chimeric antigen receptor T-cell (CAR-T) therapies for autoimmune disease.
The collaboration integrates two technologies that have been tested in clinical settings. Under the terms of the arrangement, the companies intend to advance a Phase 1 dose-escalation trial testing the Descartes-08 mRNA delivered via WestGene’s proprietary targeted lipid nanoparticles in patients with generalized myasthenia gravis.
Key timing milestones were disclosed: the clinical trial is slated to start in the second half of 2026, and clinical data are expected in the first half of 2027. The program is being developed as an in vivo route to BCMA-directed T-cell engineering that could, if successful, remove the need for the traditional ex vivo manufacturing step used in CAR-T therapies.
WestGene brings prior clinical experience with mRNA CAR-T constructs administered through its targeted lipid nanoparticle platform. Company disclosures indicate the therapy showed a favorable safety profile across multiple dosing regimens in earlier studies, with no dose-limiting toxicities, no serious adverse events, and no infusion-related reactions reported. The clinical record noted a single subject experienced Grade 1 cytokine release syndrome.
On its part, Cartesian plans to continue developing multiple next-generation internal anti-BCMA CAR constructs in addition to a BCMA-directed T-cell engager as part of an expanding mRNA payload portfolio. The licensing agreement is structured to allow a pathway for additional Cartesian payloads to enter human testing using WestGene’s delivery platform.
Financial terms disclosed in the announcement include an upfront payment to WestGene and eligibility for potential development and commercial milestone payments. The collaboration was facilitated by Uni-Pioneers, BioMed., Inc., a Chapel Hill-based firm that specializes in arranging strategic partnerships.
Context and significance
The licensing agreement represents a coordinated effort to combine an mRNA payload with a targeted lipid nanoparticle delivery system in an effort to enable in vivo CAR-T engineering. If the approach succeeds in clinical testing, it could alter the manufacturing paradigm for certain CAR-T programs by avoiding ex vivo cell processing. The near-term milestones provide a clear timeline for clinical initiation and the expected availability of trial data.