Sutro Biopharma (STRO) investor relations material

Strategic transformation and pipeline focus

• Pivoted from a late-stage asset to an early-stage clinical pipeline, emphasizing differentiated technology and value creation for shareholders and patients.

• Upgraded ADC platform with exotecan-based payloads, high DAR, and improved linker strategies for enhanced safety and efficacy.

• Focus on single and dual payload ADCs to address hard-to-treat tumors and overcome resistance.

• IND filing for lead program STRO-4 on track for the second half of the year, with first patient dosing and site activation expected this year.

• Ambition to share interim top-line results quickly and maintain transparency with investors.

Lead programs and clinical differentiation

• STRO-4 shows a 50-fold increase in exposure and higher tolerated doses in preclinical models compared to approved tissue factor ADCs.

• Demonstrated activity in multiple tumor types beyond cervical, including lung, head and neck, pancreatic, and esophageal cancers.

• No observed ocular, skin, or bleeding toxicities at high exposures, indicating a differentiated safety profile.

• Dosing strategy aims for rapid, safe escalation to effective doses in the clinic.

• STRO-6 targets integrin beta-6, a challenging but validated target in lung cancer, with strong preclinical activity and limited competition.

Dual payload innovation and business development

• Dual payload ADCs positioned as the next wave of innovation to overcome resistance and compete as best-in-class therapies.

• Ability to safely increase exposure with dual payloads, doubling dose levels compared to single payload platforms.

• Ongoing collaboration with Astellas on a dual payload ADC combining immunostimulatory and cytotoxic agents.

• Open to flexible business development, including partnerships and retaining value in key programs.

• Expecting milestone payments from Astellas in the next 9–12 months to extend cash runway.