ESSA Pharma (EPIX) Jefferies 2024 Global Healthcare Conference summary

Company overview and scientific approach

• Focuses on small molecule inhibition of androgen biology in prostate cancer, targeting the N-terminal domain of the androgen receptor, distinct from traditional anti-androgens.

• Strategy is to combine with existing anti-androgens for more complete receptor inhibition, not to compete with them.

• Currently in randomized phase 2 trials combining their drug with enzalutamide, and feasibility studies with other anti-androgens.

Clinical trial updates and data

• Phase 1 combo trial with enzalutamide showed favorable safety, tolerability, and pharmacokinetics, with 81% of patients achieving PSA90, exceeding historical benchmarks.

• Most patients in the trial were high risk for enzalutamide failure, yet deep PSA declines were observed.

• Randomized phase 2 trial compares the combination to enzalutamide alone, focusing on PSA response and PFS-2, with 80 patients in the combo arm and 40 in the control.

• Enrollment is expected to complete in Q1 2025, with data readout anticipated mid-2025.

Trial design, operations, and future plans

• Additional European sites are being added to accelerate enrollment and access a broader patient pool, as treatment patterns differ from the US.

• Inclusion/exclusion criteria remain unchanged; patient mix will be tracked for stratification.

• Exploratory endpoints include circulating tumor DNA and advanced imaging to assess response heterogeneity and identify patient subgroups.

• If phase 2 is positive, next steps include potential phase 3 trials and strategic partnerships, with interest in expanding to earlier prostate cancer settings.