Halda Begins Phase 1/2 Trial of HLD-0915 for Advanced Prostate Cancer

Halda Therapeutics, a biotechnology company situated in New Haven, Connecticut, recently announced that they have started dosing patients in their groundbreaking clinical trial aimed at evaluating a new class of cancer therapies known as RIPTAC™ therapeutics. On February 24, 2025, the company reported the first administration of HLD-0915 to a patient in the Phase 1/2 clinical trial, which is specifically targeting metastatic castration-resistant prostate cancer (mCRPC). This trial, identified as NCT06800313, represents a pivotal step in the development of these innovative small molecule therapies, designed to address significant unmet needs in cancer treatment.

The clinical trial is structured as an open-label, multi-center study, focusing on assessing the safety, tolerability, pharmacokinetics, pharmacodynamics, and anti-tumor activity of HLD-0915 when administered orally to mCRPC patients. During the initial Phase 1 of the study, researchers aim to determine the maximum tolerated dose and recommend expansion doses for HLD-0915 as a standalone treatment. Following this, Phase 2 will involve an expansion cohort to further explore the drug's efficacy and safety. It is anticipated that up to 80 patients with mCRPC could be enrolled in this study.

HLD-0915 stands out as a pioneering bifunctional small molecule therapy specifically engineered to target prostate cancer cells. It operates by orchestrating protein interactions within cancer cells, effectively disrupting essential functions that are crucial for the survival of these cells. The therapy achieves this by bringing together the androgen receptor, a tumor-specific protein, with an effector protein in a precise orientation. This interaction forms a ternary complex that promotes new protein-protein interactions, leading to the destruction of cancer cells. Halda's preclinical studies have demonstrated the therapy's capability to trigger tumor reduction and a decrease in prostate-specific antigen levels, all while maintaining a strong therapeutic index, even in models showcasing resistance to other drugs.

Halda Therapeutics is at the forefront of developing the RIPTAC™ modality, which utilizes a "hold and kill" mechanism to provide precision treatment for cancer. This innovative mechanism of action is particularly effective in overcoming cancer's typical resistance pathways, a frequent obstacle faced by modern precision oncology treatments. Beyond tackling prostate cancer, Halda is actively expanding its RIPTAC pipeline to address a range of major solid tumor types and is exploring additional therapeutic programs for severe diseases.

The initiation of this clinical trial underscores Halda Therapeutics' commitment to advancing cancer treatment through innovative approaches. By focusing on the unique capabilities of RIPTAC therapeutics, the company aims to offer new hope to patients affected by challenging cancer types, such as metastatic castration-resistant prostate cancer. As the trial progresses, Halda Therapeutics continues to explore the potential of their novel therapeutic approach, which could reinforce their position as leaders in the field of precision oncology.