UPDATE 2: HLD-0915 Shows Promising Early Results in Drug-Resistant Prostate Cancer

A first-in-human clinical trial conducted at The University of Texas MD Anderson Cancer Center has revealed encouraging early results for HLD-0915, a new oral therapy designed for patients with metastatic castration-resistant prostate cancer (mCRPC). The findings, presented at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics, indicate that HLD-0915 is well tolerated and has notable anti-tumor activity in a population of patients who have exhausted standard treatment options.

HLD-0915 represents a first-in-class approach using regulated induced proximity targeting chimera (RIPTAC) technology. This therapy acts through a ternary complex that targets both the androgen receptor (AR) and BRD4, a key regulator of cancer cell survival and resistance mechanisms. Conventional treatments in prostate cancer primarily aim at inhibiting AR signaling, but many tumors eventually adapt by activating alternate survival pathways. By simultaneously targeting AR and BRD4, HLD-0915 aims to overcome these resistance processes and suppress crucial drivers of disease progression.

In the ongoing Phase I/II clinical trial, preliminary results showed that 59% of participants who completed at least two treatment cycles achieved a PSA50 response (a reduction of prostate-specific antigen levels by at least 50%) while 32% reached PSA90 responses.

Among patients with measurable soft tissue lesions according to RECIST criteria, all demonstrated partial responses at the first imaging assessment. One additional patient with both bone and soft tissue involvement experienced complete resolution of soft tissue disease. Beyond these efficacy indicators, HLD-0915 was reported to have a favorable safety profile, an important consideration for heavily pretreated mCRPC patients.

Given its innovative mechanism and promising early activity, HLD-0915 has been granted Fast Track designation by the U.S. Food and Drug Administration, as we reported in a past article.

If further studies confirm these initial findings, HLD-0915 could represent a significant therapeutic advance for men with advanced prostate cancer who have progressed after standard hormonal therapies.

Source.

Clinical trial.