Reprogramming T Cells to Cross the Brain’s Border

What It Covers

Adaptin Bio CEO Michael Roberts explains how the company's BRITE platform uses patient-derived T cells as delivery vehicles to transport bispecific therapeutic payloads across the blood-brain barrier, with lead program APTN-101 targeting glioblastoma and a Phase 1 trial planned for early 2026.

Key Questions Answered

• •Blood-Brain Barrier Delivery Gap: Current BBB-crossing strategies — including focused ultrasound with microbubbles, receptor-mediated transcytosis, and convection-enhanced delivery — all carry significant limitations: invasiveness, localized effect only, or uncontrolled permeability. None adequately address glioblastoma's diffuse infiltration pattern, where tumor tentacles extend far beyond the visible mass seen on imaging.
• •BRITE Platform Mechanism: Adaptin isolates patient T cells via standard leukapheresis, manipulates them without genetic engineering to express BBB-crossing receptors, then links bispecific T cell engagers to those cells. This dual-component system increases large protein delivery into the brain by more than sevenfold over baseline, as demonstrated in preclinical studies.
• •APTN-101 Tumor Specificity: The lead program targets EGFRvIII, an antigen expressed exclusively on tumor cells and absent from normal tissue, paired with a CD3-binding arm that activates T cells on contact. In glioblastoma mouse models with implanted tumors behind the BBB, the therapy produced long-term survival in 70–80% of animals with minimal off-target toxicity signals.
• •Scalable, Low-Cost Manufacturing: Because T cells are manipulated rather than genetically engineered, Adaptin avoids the cost of viral vectors required for CAR-T production. A single leukapheresis expansion can yield tens to hundreds of potential doses. The bispecific engager component is manufactured separately at a third-party CMO, keeping overall production costs lower and timelines shorter.
• •Pipeline Adaptability for Tumor Escape: Glioblastoma cells alter antigen expression under therapeutic pressure, a primary reason single-target therapies fail. Adaptin's platform is designed to swap targeting components as tumors evolve — APTN-102 addresses a secondary tumor antigen — enabling sequential or combination targeting that tracks tumor changes rather than treating a static molecular profile.