About

Focused on Designing Meaningful Medicines

Quellis was founded to deliver best-in-class therapies to patients suffering serious rare diseases – and underserved by current treatment options. The Company is based in Boston, and is led by partners from the biotech incubator Viridian LLC in collaboration with team at biotech accelerator Xontogeny LLC, and with funding from the Perceptive Xontogeny Venture Fund. The Quellis team has deep experience in mAb discovery and development, company creation, and private and public biotech investment. Our shared goal is to create meaningful medicines for every disease we target.

The lead Quellis program targets a life-threatening and burdensome rare disease. Approved medications leave substantial unmet needs for these patients; Quellis is pursuing a product-focused hypothesis to discover a new molecule with best-in-class performance. The Company is currently optimizing several new monoclonal antibodies (mAbs) leveraging a validated mechanism of action.  We are engineering these mAbs to include features intended to deliver greater value and improve patients’ lives. As part of these efforts, the Company plans to incorporate Xencor, Inc.’s Xtend™ Fc technology, for which the Company holds a target-exclusive license from Xencor.  Xtend is a clinically proven antibody technology that provides for improved antibody half-life and thereby reduces the size and frequency of doses that patients require compared to a standard antibody drug candidate.