Janux Therapeutics (JANX) Investor Update summary

Clinical program focus and patient population

• Development targets early line, taxane-naive metastatic castration-resistant prostate cancer (mCRPC) patients, a rapidly growing segment with over 38,000 potential candidates in the US.

• Disease burden analysis shows improved efficacy in patients with lower tumor burden, supporting earlier line therapy.

Mechanism of action and platform innovations

• JANX007 is a tumor-activated T-cell engager targeting PSMA, using peptide masks and cleavable linkers to activate only in the tumor microenvironment and minimize off-tumor toxicity.

• The half-life extender is cleaved upon tumor activation, ensuring rapid clearance from healthy tissue and contributing to a favorable safety profile.

Clinical data and efficacy outcomes

• Over 100 patients have been dosed, with durable PSA reductions and radiographic progression-free survival (rPFS) up to 8.9 months for every-other-week (Q2W) dosing.

• Deep PSA reductions (PSA50 in 73%, PSA90 in 26% at ≥2mg) and RECIST responses (ORR 30% at >2mg) observed, with rapid, deep PSA declines in taxane-naive patients.