Cullinan Therapeutics (NASDAQ:CGEM) executives highlighted upcoming clinical milestones for the company’s two high-priority T-cell engager programs during remarks at the 46th Annual TD Cowen Healthcare Conference, pointing to multiple data readouts in autoimmune disease in 2026 and an expansion plan for its acute myeloid leukemia (AML) program.
Management frames 2026 as a catalyst year
President and CEO Nadim Ahmed told attendees that 2026 “could be really transformational” for Cullinan, citing planned catalysts “across all of our programs,” with particular emphasis on CLN-978, a CD19xCD3 T-cell engager being developed for autoimmune diseases, and CLN-049, an FLT3xCD3 T-cell engager in AML.
CLN-978: timelines for lupus, rheumatoid arthritis, and Sjögren’s disease
Management said CLN-978 is being evaluated in three indications—rheumatoid arthritis (RA), lupus, and Sjögren’s disease—with multiple clinical updates planned this year:
- Q2 2026: Initial clinical data for lupus and RA (from modified single ascending dose portions of studies)
- Q3 2026: Multi-dose data for RA
- Q4 2026: Initial clinical data for Sjögren’s disease
Chief Medical Officer Jeff Jones said the Q2 update is expected to show dose-response relationships for biomarkers, “particularly B-cell depletion,” in peripheral blood in both RA and lupus, as well as tissue-level B-cell depletion in RA. He added that the single-dose setting carries limitations for demonstrating efficacy, describing expectations for efficacy after a single therapeutic dose as “relatively small,” but said the data should help build confidence for the subsequent multi-dose RA readout in Q3.
Jones also said the company aims to provide what he characterized as a more systematic view of dose response, pharmacodynamics, and the “practical aspects of next steps in drug development,” arguing that much of the field’s current CD19 T-cell redirecting data consists of investigator-initiated case reports with a high signal-to-noise challenge for investors trying to interpret outcomes.
Safety and efficacy goals discussed for autoimmune development
On safety targets, Jones said a Grade 3 cytokine release syndrome (CRS) event is considered a dose-limiting toxicity by FDA, and that the company is focused on reducing CRS overall, particularly minimizing Grade 2 CRS. He said Cullinan believes Grade 2 CRS rates of “10% or less” would be acceptable based on interactions with key opinion leaders, while noting Grade 1 CRS is generally manageable. He also said the company is working to prevent neurotoxicity, “most specifically ICANS.”
On efficacy expectations, Ahmed framed the value proposition as the potential for monotherapy activity that enables patients to come off chronic background immunosuppressive therapy. He said physicians he has spoken with view “treatment-free remissions” as a key differentiator versus current biologics that are typically layered on top of ongoing immunosuppression. Ahmed said that if a therapy could deliver treatment-free remission in “20%–30%” of patients “at a minimum,” it would drive widespread adoption, while adding that the company would aim higher.
Regarding patient numbers for the Q2 update, Jones said the company previously disclosed enrolling to the 30 microgram cohort in both SLE and RA. He said the minimum expected dataset would include at least nine SLE patients and seven RA patients, adding that totals could be higher due to potential further escalation and backfill at dose levels of interest.
CLN-049: positioning an immunotherapy approach in AML
Turning to oncology, Jones said AML has seen slow therapeutic progress, with standard 7+3 induction dating to the early 1970s and immunotherapy representing a notable gap compared with other hematologic malignancies. He said the company views CLN-049 as a first-in-class opportunity to bring an immunotherapeutic mechanism to AML and potentially address a broad patient group.
Jones referenced data presented at ASH in December, highlighting a composite complete response (CR) rate of 31% at the highest dose tested (12 micrograms per kilogram). He said this was competitive with response rates observed for recently approved AML drugs over the past decade, which he characterized as ranging from roughly 23% to “30-some percent,” with reported durability in the “4.5 to six, seven months” range. He noted Cullinan’s durability data were still immature at the time, but said that if the response rate is replicated in a larger dataset, it could support an accelerated approval pathway in a broad AML population.
Jones also said the company has not observed a biomarker that clearly predicts response and said FLT3 expression cutoffs have not appeared necessary based on data to date. He discussed different “bars for success” across AML subgroups and singled out patients with TP53 mutations as having particularly poor outcomes, saying a complete response rate of 20% with four months’ durability would be clinically meaningful in that group given a median life expectancy of around six months in newly diagnosed TP53-mutated AML, as he described it.
On trial conduct, Jones said the company had not identified an MTD as of ASH and that its intent was not necessarily to dose to MTD. He said there was still evidence of a dose response through 12 micrograms/kg with a retained therapeutic index, leaving the option to continue escalation to seek incremental efficacy. He added that if safety worsened or efficacy plateaued, that would guide a shift to expansion around already active doses.
Looking ahead, Jones said Cullinan plans to complete dose escalation “early in 2026” and to begin the expansion phase in Q2 2026. He said the expansion plan includes exploring at least two doses in relapsed AML, with a separate cohort for TP53-mutated patients, including an opportunity to explore monotherapy in previously untreated TP53-mutated AML where he said there is no established standard of care. Jones said that at the time of ASH the company had treated at least 53 patients, and he suggested that by late 2026, responding patients should generally have about six months of follow-up, which he described as an important landmark.
About Cullinan Therapeutics (NASDAQ:CGEM)
Cullinan Therapeutics, Inc, a biopharmaceutical company, focuses on developing oncology therapies for cancer patients in the United States. The company's lead program comprises CLN-619, a monoclonal antibody that is in Phase I clinical trial for the treatment of solid tumors. Its development portfolio also includes CLN-049, a humanized bispecific antibody that is in Phase I clinical trial for the treatment of acute myeloid leukemia or myelodysplastic syndrome; CLN-418, a human bispecific immune activator that is in Phase 1 clinical trial for the treatment of multiple solid tumors; and Zipalertinib, a bioavailable small-molecule for treating patients with non-small cell lung cancer.
