Cullinan's CLN-978 shows promise in lupus and rheumatoid arthritis trials

Cullinan Therapeutics has released early clinical results for its experimental drug CLN-978. The findings come from two Phase 1 trials involving patients with refractory lupus (SLE) and rheumatoid arthritis (RA). The company will discuss these results in detail at an upcoming Immunology Day event on June 10. The drug, a CD19xCD3 T cell engager, demonstrated promising effects in both studies. In the OUTRACE SLE trial, 71% of patients saw their disease activity score drop by at least four points on the hSLEDAI scale. A further 82% experienced an over 80% reduction in peripheral B cell counts. Meanwhile, in the OUTRACE RA study, 71% of participants showed improved disease activity, while 67% achieved BLOQ (below the limit of quantification) with doses of 20 micrograms or higher.

Safety data also proved encouraging. CLN-978 was well tolerated, with most cytokine release syndrome (CRS) events classified as mild (Grade 1). No immune effector cell-associated neurotoxicity syndrome (ICANS) cases were reported.

The company will host an Immunology Day on June 10 to present these findings in full. Leading experts Dr. Ricardo Grieshaber-Bouyer and Dr. John Tesser will join Cullinan’s leadership team at the event. Investors and analysts can attend in person or watch via a live webcast on the company’s investor relations website. The Phase 1 results suggest CLN-978 could offer clinical benefits for patients with difficult-to-treat autoimmune diseases. The drug’s ability to deplete B cells deeply while maintaining a manageable safety profile will likely be a focus of further discussion. Full details will be shared during the upcoming Immunology Day presentation.