Promising early safety data as Quell Therapeutics advances QEL-005 to second dose cohort in CHILL Phase 1/2 trial

Quell Therapeutics Ltd announced today that QEL-005, its CD19 B-cell activated Phenotype-Locked™ engineered nTreg therapy, has advanced to the second planned dose cohort in the CHILL Phase 1/2 clinical study. The decision follows completion of the first dose cohort in which QEL-005 was well tolerated, with no dose-limiting toxicities (DLTs), no treatment-related adverse events of special interest (AESIs) and no serious adverse events (SAEs).

In the first dose cohort, no acute toxicities were observed, including infusion reactions, cytokine release syndrome, local immune effector cell-associated toxicity syndrome, or immune effector cell-associated neurotoxicity syndrome, and no elevations in cytokines were observed. All participants were fit for discharge on the next morning following infusion. These early observations support the potential of QEL-005 to meet its target product profile as a transformational outpatient therapy for complex autoimmunity.

Professor Chris Buckley, Chief Investigator of the CHILL study, said:

Complex autoimmunity is driven by multiple pathogenic cell types. CHILL represents a unique opportunity to investigate the ability of nTregs to regulate - or ‘chill’ - that complex immune network, with the aim of achieving disease reset with benign safety. Completion of the first dose cohort provides an encouraging early indication of the potential safety of this therapeutic modality.

CHILL is a Phase 1/2 study evaluating QEL-005, Quell’s engineered nTreg therapy for complex autoimmune diseases, including difficult-to-treat rheumatoid arthritis (D2TRA) and systemic sclerosis (SSc), using a lymphodepletion-free regimen. The first participant was dosed in the UK at Leeds Teaching Hospitals NHS Trust, followed by two participants at Oxford University Hospitals NHS Foundation Trust. Successful completion of this initial cohort marks an important milestone for the program.

The CHILL study is enrolling at seven sites in the UK, with a further four sites across Germany and Spain. Rapid study start-up has been a defining feature of CHILL, supported by outstanding engagement from physicians and patients. Initial clinical data from CHILL are expected in H1 2027.

Luke Devey, Chief Medical Officer at Quell Therapeutics, said:

We are encouraged by the early safety profile of QEL-005 and look forward to seeing clinical efficacy data, underpinned by deep translational insights, as the study progresses, with initial six-month data expected in H1 2027. We would like to thank the patients who have entrusted us with their care.

Professor Francesco Del Galdo, Principal Investigator at Leeds Teaching Hospitals NHS Trust, said:

We were thrilled to dose the first CHILL patient in the world. The team worked together admirably, and it was rewarding to see the patient able to return home the day after dosing. This potentially transformational treatment is an important step forward for patients, and I am proud to contribute to this work.