GondolaBio Announces Positive Phase 2a Results Demonstrating 79% Plasma Protoporphyrin IX Reduction and Disease-Modifying Potential of PORT-77 for Erythropoietic Protoporphyria
PALO ALTO, Calif.--( BUSINESS WIRE)--GondolaBio, a clinical-stage biopharmaceutical company developing novel medicines for patients living with genetic diseases, on behalf of its affiliate Portal Therapeutics, today announced positive data from its Phase 2a GATEWAY trial of PORT-77 in patients with erythropoietic protoporphyria (EPP). PORT-77 is a novel investigational oral, small molecule ABCG2 inhibitor designed to treat EPP and X-linked protoporphyria (XLP), two rare genetic disorders characterized by severe, lifelong photosensitivity and liver complications.
"These data represent an important milestone, highlighting PORT-77’s potential to be a disease modifying therapy by significantly reducing PPIX in plasma, the most physiologically relevant blood component for these conditions, which may address the significant unmet need in people living with EPP and XLP," said Pete Schmidt, M.D., M.Sc., Chief Medical Officer of Portal Therapeutics. "Notably, these results demonstrate PORT-77’s potential for leading efficacy, safety, and speed to onset, with rapid and profound reductions in plasma PPIX within hours of dosing. We are encouraged by the magnitude and speed of these reductions, which may translate to patients tolerating more time in the sun and improved quality of life."
The Phase 2a GATEWAY study was a blinded, randomized, placebo-controlled crossover trial evaluating the safety, tolerability, pharmacokinetics (PK), and pharmacodynamic (PD) effects on plasma PPIX of PORT-77 in adults with EPP. Nineteen enrolled participants received placebo followed by 180 mg of PORT-77 oral suspension once daily (QD) or 300 mg twice daily (BID) for four days.
These data were presented at the European Hematology Association (EHA) 2026 Congress in Stockholm, Sweden this month. Key results include:
Based on these results and general alignment at the End-of-Phase 2 meeting with the U.S. Food and Drug Administration (FDA) this month, GondolaBio plans to initiate the global Phase 2b/3 PATHWAY trial evaluating the safety and efficacy of PORT-77 in patients with EPP and XLP in Q3 2026. In tandem, the company is conducting the stEPP study, a global observational study designed to further characterize disease burden, phototoxicity, sunlight exposure and plasma PPIX variability in patients with EPP and XLP.
Patient and Clinician Webinar Details
GondolaBio will host three webinars during the week of June 22, 2026 to share these data and development plans for PORT-77 with the patient and clinician communities. Details to register and/or access the webinars live are as follows:
About Erythropoietic Protoporphyria and X-linked Protoporphyria
EPP and XLP, which affect greater than 25,000 people in the U.S. and EU, are genetic photodermatoses that result in the accumulation of protoporphyrin IX (PPIX). Affected patients experience cutaneous damage and excruciating pain when exposed to sunlight. Approximately 20-30% of patients with EPP/XLP will experience some type of liver damage with up to 5% of patients progressing to acute liver failure and requiring a liver transplant. There are no approved disease-modifying treatments available.
About PORT-77
PORT-77 is an oral, small molecule ABCG2 inhibitor currently in Phase 2 development for EPP and XLP. PORT-77 is designed to modify efflux of PPIX from the red blood cell to the plasma and from hepatocytes to the biliary tract, representing a potentially disease-modifying, leading treatment that addresses the root cause of EPP and XLP. The ongoing clinical program is designed to determine if PORT-77 can effectively reduce plasma PPIX to improve sunlight sensitivity and reduce liver damage.
About GondolaBio
GondolaBio is a clinical-stage biopharmaceutical company focused on developing novel medicines for patients living with genetic diseases. A sister company of BridgeBio Pharma, GondolaBio aims to leverage cutting-edge biological research to create breakthrough medicines addressing high unmet needs across multiple therapeutic areas, modalities, and stages ranging from early discovery to clinical development. Its team of experienced drug discoverers, developers and innovators are committed to translating advances in genetic science into medicines that can help patients as quickly as possible.