Day One Biopharmaceuticals (DAWN) Piper Sandler 36th Annual Healthcare Conference summary

Company overview and pipeline

• Focuses on oncology therapeutics for children and adults, with equal intensity across programs.

• Ojemda is approved for relapsed/refractory pediatric low-grade glioma (pLGG) and is being developed for frontline use.

• DAY301, a PTK7-targeting antibody-drug conjugate, will begin dosing patients in late 2023 or early 2024.

Ojemda launch and market dynamics

• Ojemda is the first approved therapy for relapsed pLGG with RAF alterations, offering strong efficacy, safety, and convenient oral dosing.

• Consistent new patient starts since launch, with an estimated 2,000–3,000 relapsed pLGG patients on treatment in the U.S.

• High physician awareness (100%) and intent to use (90%) reported; commercial efforts focus on expanding prescriber base and earlier-line use.

• Persistence on therapy is high, with less than 10% discontinuation between Q2 and Q3 2023.

• Drug holidays after two years of treatment show low rates of tumor rebound, and responses can be recaptured upon retreatment.

Treatment paradigm and competitive landscape

• Strategy aims to move Ojemda use from later lines to second line, increasing eligible patient pool and potential for repeat use.

• Ojemda is currently the only approved therapy for pLGG with RAF alterations, with no near-term competitors in late-stage development.

• Off-label and frontline use is limited but expected to grow with more data and eventual approval.