Hillhurst Biopharmaceuticals Initiates Phase 2a Trial of Oral Carbon Monoxide Therapy for Sickle Cell Disease
Key Insights
Hillhurst Biopharmaceuticals (search) has dosed the first patient in a Phase 2a clinical trial evaluating HBI-002, an oral low-dose carbon monoxide therapy for sickle cell disease (search).
The open-label study will assess safety and tolerability while collecting biomarker and pharmacokinetic data to inform a larger Phase 2b trial planned for 2026.
HBI-002 represents a novel approach to treating sickle cell disease (search), targeting the prevention of painful vaso-occlusive crises in a condition with significant unmet medical need.
Hillhurst Biopharmaceuticals (search) has achieved a significant clinical milestone by dosing the first patient in its Phase 2a trial of HBI-002, an investigational oral carbon monoxide therapy for sickle cell disease (search). The San Diego-based clinical-stage biopharmaceutical company announced the enrollment on July 23, 2025, marking a critical step forward in developing novel treatments for this devastating genetic disorder.
"Dosing the first subject marks a significant milestone," said co-founder and Chief Executive Officer Andrew Gomperts. "There remains a substantial unmet medical need in preventing the painful vaso-occlusive crises experienced by sickle cell patients. We are hopeful that our novel drug product can provide meaningful relief for patients and families."
Novel Therapeutic Approach
HBI-002 represents an innovative approach to sickle cell disease (search) treatment, utilizing oral low-dose carbon monoxide as the active therapeutic component. The investigational drug is designed for chronic use in a home setting, potentially offering patients greater convenience and accessibility compared to traditional treatment modalities.
The therapy is built on Hillhurst's proprietary GLASS platform, which enables the development of novel oral liquid drug products based on known inhaled therapeutics. This platform technology overcomes limitations associated with traditional inhaled delivery methods, potentially expanding treatment options for patients with various conditions.
Phase 2a Trial Design
The current Phase 2a clinical trial is structured as an open-label study designed to assess the safety and tolerability of HBI-002 in patients with sickle cell disease (search). Beyond safety evaluation, the trial will collect biomarker and pharmacokinetic data, providing preliminary insights into the investigational therapy's potential efficacy.
Data generated from this Phase 2a study will inform the design of a larger Phase 2b clinical trial, which Hillhurst plans to initiate in 2026. The company expects to report first readout from the current trial by the end of 2025.
Addressing Critical Medical Need
Sickle cell disease (search) represents a significant medical challenge, characterized as a genetic disorder that causes severe vaso-occlusive pain crises. The condition is associated with serious clinical consequences, including stroke (search), heart disease (search), kidney disease (search), and premature death. The average life expectancy of sickle cell disease patients in the United States is only 45 years, underscoring the urgent need for more effective treatments.
Broader Therapeutic Potential
While the current trial focuses on sickle cell disease (search), HBI-002's therapeutic potential may extend beyond this indication. Other potential applications for the oral carbon monoxide therapy include conditions associated with inflammation and cell death, such as Parkinson's disease (search), suggesting a broader platform opportunity for Hillhurst's technology.
Development History
The advancement to Phase 2a follows successful completion of a Phase 1 clinical study in healthy subjects conducted under an Investigational New Drug application. This foundational work established the safety profile necessary to advance into patient populations.
The research program is supported by the National Heart, Lung, and Blood Institute under grant number 2R44HL131065-05, reflecting federal recognition of the therapeutic approach's potential significance.