Phio Pharmaceuticals (PHIO) Corporate presentation summary

Value proposition and market opportunity

• Targets cutaneous squamous cell carcinoma (cSCC), the second most common solid tumor, with ~1.8M annual cases and a $20B addressable market.

• Current treatment regimens for cSCC are unsatisfactory, with mortality rates approaching those of melanoma.

• No FDA-approved drug therapy exists for early-stage cSCC; invasive surgery is the standard of care.

• PH-762 and PH-894 programs address significant unmet needs in oncology, with additional potential in autoimmune and cosmetic indications.

Technology and intellectual property

• INTASYL® siRNA technology enables precise gene silencing, reactivating immune cells to kill tumor cells.

• Patented asymmetric siRNA duplex design enhances specificity, stability, and delivery to target cells.

• 54 patents issued, with protection extending to 2044, covering chemistry, compounds, gene targets, and indications.

• Platform versatility allows targeting of multiple genes relevant to oncology, autoimmune, and cosmetic applications.

Clinical development and results

• PH-762 (PD-1 silencer) completed a Phase 1b dose-escalation trial in cSCC, with 22 patients treated.

• Final cohort showed 85% pathological response and 100% tumor clearance in 4 of 6 responders.

• No immune-related or treatment-limiting toxicities observed across five dose cohorts, even at 20-fold dose escalation.

• PH-894 (BRD4 silencer) completed IND-enabling studies, showing dual action (tumor killing and immune activation) and a clean toxicology profile.