Precision BioSciences (DTIL) investor relations material

Platform overview and technology

• ARCUS nucleases are proprietary, in-house designed gene-editing enzymes with unique features: precise cut, small size, and single-component simplicity.

• The platform enables efficient gene insertion and editing, offering advantages in delivery and therapeutic flexibility.

• ARCUS is applied in programs targeting hepatitis B and Duchenne muscular dystrophy, leveraging its differentiators for clinical impact.

Hepatitis B (PBGENE-HBV) program updates

• PBGENE-HBV uniquely targets and eliminates cccDNA, the source of new HBV particles, independent of baseline S antigen levels.

• Biopsy and pgRNA data show durable elimination of cccDNA-derived transcripts and undetectable pgRNA in all patients with baseline detection.

• Safety profile improved with a new infusion protocol, mitigating inflammatory responses and enhancing tolerability.

• Dose optimization ongoing, with expansion cohorts at 0.1 and 0.65 mg/kg; next data update expected before year-end 2026.

Duchenne muscular dystrophy (PBGENE-DMD) program updates

• First patient dosed in August 2026; second site activated, with initial safety data expected by year-end.

• Muscle biopsies at pre-treatment, 3, and 12 months will assess near full-length dystrophin expression, with meaningful levels anticipated at 5% or higher.

• PBGENE-DMD offers a one-time DNA-level correction, potentially applicable to 60% of DMD patients, and contrasts with repeat-administered exon skippers and synthetic micro-dystrophin approaches.

• AAV dose is set at the lower end of the class, with high full capsid ratio to reduce toxicity; safety-first immune modulation strategy adopted.