The capital narrative of TCE self-immunity is about to face a major test.

On June 10, two weeks from now, Cullinan Therapeutics will announce two sets of clinical data. One targets CD19, and the other targets BCMA. The multi-dose cohort data of more than 30 patients with lupus and rheumatoid arthritis will be made public for the first time on this day.

The shift of T-cell engagers from hematological tumors to autoimmune diseases is the hottest topic in the entire pharmaceutical industry in 2026. Cullinan's differentiated target layout, with CD19 responsible for clearing B cells and BCMA for clearing plasma cells, precisely covers all links in the production of autoantibodies. The two sets of data will directly answer the questions that the industry is most concerned about: How deeply can TCE clear in the field of autoimmune diseases, how long can the effect last, and is the safety up to standard?

This means that this is not an ordinary clinical data readout, but a major directional test: The answers to these questions will directly affect the capital narrative rhythm of the entire TCE autoimmune disease track and influence the next direction of billions of dollars in bets.

01 Big Pharma's Bets

Big pharmaceutical companies have already cast their votes with their checkbooks.

In March 2026, Gilead acquired Ouro Medicines for $2.175 billion to obtain its BCMA×CD3 TCE assets.

In May, UCB acquired Candid Therapeutics for $2.2 billion, with an upfront payment of $2 billion, accounting for more than 90% of the total price. This payment structure is extremely rare in MNC mergers and acquisitions. The proportion of the upfront payment reflects the buyer's judgment on the certainty of the assets. Putting 91% upfront indicates that UCB has seen sufficiently convincing early-stage data.

Candid's core product, cizutamig, is a BCMA×CD3 bispecific antibody. It has completed dosing in 80 patients, about half of whom are for autoimmune diseases. Clinical data show that the drug has achieved efficient clearance of B cells and plasma cells in deep tissues. BCMA targets plasma cells, which are more downstream than CD19, resulting in more thorough clearance and lower recurrence risk. Based on these data, Candid plans to initiate two global phase II clinical trials for autoimmune indications in 2026.

In addition, it is worth noting that 16 publicly announced BD transactions in the field of autoimmune TCE have been completed within half a year, and the core assets of 10 of them come from China.

Big pharmaceutical companies' checks don't lie. They are telling the market with the speed of mergers and acquisitions that autoimmune TCE is not an option but a must-have.

02 Why TCE?

The answer lies in the underlying defects of traditional autoimmune drugs.

The global market size of autoimmune drugs has exceeded $200 billion. In the top 10 global drug sales in 2024, autoimmune drugs accounted for four positions. However, this multi-billion-dollar market is being eroded by the high homogenization of TNF inhibitors and IL inhibitors. The annual sales of Dupixent of $20 billion are the ceiling that the existing paradigm can reach.

The problem lies in the mechanism: Existing drugs only "inhibit" the immune response, rather than "reset" the immune system. Monoclonal antibodies targeting B cells, such as rituximab and obinutuzumab, are the sharpest weapons in the existing arsenal, but their depth of B cell depletion is always limited. Tissue-resident B cells and long-lived plasma cells hide deep in the spleen and bone marrow, which monoclonal antibodies cannot reach at all. A large number of CD20-negative plasma cells in patients' bodies continuously produce autoantibodies, which is the root cause of the repeated recurrence of the disease. If the drugs cannot clear the pathogenic cells, the immune system will never be able to re-establish normal immune tolerance.

The concept of immune reset was pushed to the forefront under this bottleneck. Its logic is completely different from existing therapies: Instead of relying on lifelong medication to suppress symptoms, it aims to exhaust pathological immune memory through deep clearance and allow the immune system to restore self-tolerance during reconstruction.

CAR-T has proven this path in the field of oncology, but there are two insurmountable drawbacks when applied to autoimmune diseases: It requires chemotherapy to clear lymphocytes, and the preparation of autologous cells has a long cycle and extremely high costs.

TCE stands in contrast to CAR-T: It does not require lymphocyte clearance, is an "off-the-shelf" product and can be used at any time; it can control the depth and rhythm of treatment through repeated dosing, and the withdrawal window is much wider than that of CAR-T; the large-scale production cost is much lower than that of CAR-T, naturally covering a wider range of patients.

CD19 and BCMA are currently the two most core targets, corresponding to B cells and plasma cells respectively, covering all links in the production of autoantibodies. Cullinan is one of the few companies that bet on both targets at the same time. Its clinical data will directly verify whether TCE can achieve deep clearance in the field of autoimmune diseases. And whether it can achieve deep clearance will directly determine the capital narrative of this track.

03 Cullinan's Double-Target Bet

Cullinan holds two TCEs: CLN-978 targets CD19×CD3, and velinotamig targets BCMA×CD3, covering all key nodes in the B cell development lineage from start to end.

CD19 is expressed in the early and middle stages of B cell development and is responsible for clearing most B cells; BCMA is expressed in the plasma cell stage. Plasma cells are the main source of autoantibody production and are also the remaining cells hiding in the deepest part. Blocking both ends leaves almost no dead ends for clearance.

CLN-978 is a second-generation molecule specifically designed for autoimmune scenarios. On the CD19×CD3 chain, Amgen's Blincyto was launched as early as 2014, but its indications are limited to hematological tumors. It has a half-life of only two hours and requires continuous infusion, making it almost useless in the field of autoimmune diseases. CLN-978 makes the formation of immune synapses more controllable, has a longer half-life, and can be administered by subcutaneous injection.

Cullinan's possession of both CD19 TCE and BCMA TCE means that it can compare the clinical response differences between the two targets under the same disease background. This combined advantage is unique in the current TCE track.

The data readout on June 10 will directly answer three questions: Is the clearance thorough enough, can the remission be maintained, and is the safety up to standard? If the data is not strong enough, this wave of enthusiasm is just a bubble; if the data is strong enough, the next big deal will follow immediately.

04 China's Position

Chinese companies' position in the TCE track is similar to that in the early days of the ADC era: They own a large number of early-stage assets and are the core supply source for global MNCs to sweep up.

According to the statistics of Guotai Haitong, among the 16 publicly announced BD transactions in the autoimmune TCE track, the core assets of 10 transactions come from China. In the pipeline of Candid, which was acquired by UCB, many molecules have their origins in China. In January 2026, Zai Lab signed a TCE research service agreement with WuXi Biologics; in February, WuXi Biologics reached an overseas cooperation with Vertex on a trispecific TCE; in March, Ascentage Pharma reached a global licensing cooperation with UCB on a CD19×CD3 bispecific antibody, with an upfront payment of $60 million and total milestones exceeding $1.1 billion.

Chinese companies show a structural supply capacity in the TCE track: high density of early-stage molecule reserves, obvious differentiation in target selection, and fast delivery of preclinical data.

Three years ago, the ADC track almost replicated the same narrative: MNCs were facing the patent cliff, Chinese companies held a rich pool of early-stage pipelines, and BD transactions changed from single tests to large-scale acquisitions.

The difference is that the target concentration of TCE is much lower than that of ADC. ADC has a serious clustering problem around HER2, TROP2, and CLDN18.2, while TCE is differentiating in multiple directions such as CD38, CD138, and GPRC5D in addition to CD19 and BCMA. The dispersion of targets means that the risk of valuation bubbles is diluted, and Chinese companies have more space for differentiated layout.

Therefore, TCE is not a simple copy of ADC. Its targets are more diverse, the mechanism is more complex, and clinical development is more difficult to standardize. This means that the era of simply relying on the density of early-stage pipelines to obtain BD transactions will not last long. In the next stage, for Chinese companies in the TCE track, only those who can present systematic clinical data can take the main seat at the negotiation table.

This article is written based on publicly available information and is only for information exchange, and does not constitute any investment advice.

This article is from the WeChat official account "Medical Shine", author: Zhang Qinghuan, published by 36Kr with authorization.