Gritstone bio (GRTS.Q) Goldman Sachs 45th Annual Global Healthcare Conference summary

Oncology pipeline and key drivers

• Focus on cancer immunotherapy, particularly cancer vaccines targeting neoantigens, with GRANITE as the lead program.

• Mature progression-free survival (PFS) data from the GRANITE study in first-line metastatic MSS colorectal cancer expected in Q3, with overall survival (OS) data anticipated mid-2025.

• GRANITE uses a personalized approach, leveraging the EDGE epitope identification platform and viral vector delivery to drive robust T cell responses.

• Preliminary data show PFS benefit (hazard ratio 0.82 overall, 0.52 in high-risk subgroup), with mature data expected to clarify efficacy.

• Positive phase II results would lead to an end-of-phase II FDA meeting and potential phase III trial, with expansion opportunities into other tumor types.

Clinical trial design and biomarker strategy

• Randomized trial design compares standard maintenance therapy with or without GRANITE vaccine regimen after induction chemotherapy.

• Initial focus on ctDNA as a biomarker was limited by endpoint definition and patient population kinetics; future focus will be on clinical endpoints (PFS, OS) while continuing to collect ctDNA data.

• Statistical analysis uses a pre-specified piecewise approach, standard in oncology, to account for induction phase events.

• High censoring in preliminary data expected to decrease with upcoming mature data, providing clearer efficacy signals.

Infectious disease pipeline and partnerships

• Infectious disease programs include both prophylactic (e.g., next-generation SARS-CoV-2) and therapeutic (e.g., HIV cure) vaccines.

• Next-generation SARS-CoV-2 vaccines show durable immune responses; a large BARDA-funded head-to-head study is planned, pending manufacturing updates.

• Partnerships span governments, NGOs (e.g., CEPI, Gates Foundation), and biopharma, with various deal structures from single-pathogen to broad collaborations.

• Infectious disease programs are largely externally funded, allowing focus on oncology while leveraging platform capabilities.