Cambridge, Massachusetts-based Stipple Bio Inc., has entered a multi-target license agreement with Switzerland-based Lonza (SIX: LONN) to access the CDMO's clinically validated antibody-drug conjugate platform across multiple oncology programs, including its lead candidate STP-100. The deal pairs Stipple Bio's Pointillist Platform — which identifies tumor-specific cell surface epitopes — with Lonza's site-specific conjugation technologies to generate precision ADCs designed to minimize on-target, off-tumor toxicity. STP-100 is expected to enter early clinical studies in 2027.
Financial terms were not fully disclosed. Lonza is eligible to receive upfront, clinical, regulatory, and commercial milestone payments, plus royalties on net sales of resulting products. The specific upfront amount, milestone values, and royalty rates were not made public.
Deal context
The Stipple Bio license agreement grants access to three core components of Lonza's ADC platform: GlycoConnect antibody conjugation technology, HydraSpace polar spacer technology, and a toxSYN linker payload. Together, these enable site-specific conjugation at the native Fc glycan of any IgG1 antibody, producing homogeneous ADCs with a defined drug-antibody ratio without requiring antibody re-engineering.
The mechanistic rationale centers on improving therapeutic index. GlycoConnect uses chemoenzymatic glycan remodeling to install a bioorthogonal azide handle at the Fc Asn297 glycan site, followed by metal-free click chemistry to attach the linker-payload. The glycan pocket location provides steric protection for the conjugate in circulation. HydraSpace addresses a common limitation of potent payloads — hydrophobicity-driven aggregation and accelerated clearance — by inserting a polar spacer between the attachment point and the drug. The toxSYN component provides the cytotoxic warhead.
Stipple Bio's contribution is upstream target identification. The company's Pointillist Platform screens for antibody binders against intact living tumor cells while applying counter-selection against normal tissue, identifying epitopes that are physically accessible on tumor cells but not on the same protein expressed in healthy tissue. The specific target antigen for STP-100 has not been publicly disclosed, nor has the indication. The platform is described by the company as modality-agnostic, with identified epitopes potentially applicable to ADCs, T-cell engagers, or radiopharmaceuticals.