
QEL-005
B cell (CD19)-activated Phenotype-Locked nTregs
- D2T RA
- Systemic sclerosis
Phase I/II · CHILL study
In Complex Autoimmunity - patients cycle through multiple ineffective treatments, accruing damage to their tissues and organs
Imagine a Different Future – when patients could receive a single infusion that durably controlled their autoimmunity, with minimal adverse events
Our Approach - At Quell, we engineer nTregs (natural T-regulatory cells) designed to do just that – durable resolution of complex autoimmune diseases - simple, safe and transformational outcomes from a single outpatient dose

Our ambition
Designed for broad and durable control the whole pathogenic immune network, durably.
Target Profile: a benign one-and-done outpatient therapy with no lymphodepletion.

The Need
For people with severe, refractory autoimmune disease, existing treatments often fall short, leaving patients at risk of progressive tissue and organ damage, disability, and a diminished quality of life.
Most potentially transformative therapies in development for autoimmunity centre on therapies originally designed for oncology. While potentially efficacious, these therapies may also cause substantial toxicity. Autoimmunity patients desperately need transformational AND safe therapies.
Quell is developing potentially transformative therapies designed specifically for the needs in complex autoimmunity to safely restore immune balance.

Our Product
Autoimmune disease is driven by many immune cell types working together, not a single culprit.
Broad control. Quell's engineered nTregs are designed to restore broad control across multiple cell types involved in complex autoimmune inflammation, including autoreactive T and B cells and inflammatory cytokines, and to steer macrophages and fibroblasts towards tissue repair.
Built-in stability. Our Phenotype-Lock™ technology is designed to keep nTregs stable, even under inflammatory stress, without producing pro-inflammatory cytokines to avoid the toxicities linked to cell-depleting therapies, such as cytokine release syndrome (CRS) or local immune effector cell-associated toxicity syndrome (LICATS).
Our pipeline
Our pipeline-in-a-product candidates are designed to address multiple autoimmune diseases.
Explore our pipeline

B cell (CD19)-activated Phenotype-Locked nTregs
Phase I/II · CHILL study

Th17-activated Phenotype-Locked nTregs
IND/CTA filings planned H1 2027
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