Forma Therapeutics Holdings, Inc. announced positive initial results from a Phase 1 trial of its novel CBP/p300 inhibitor, the oral small molecule FT-7051, in men with metastatic castration-resistant prostate cancer (mCRPC). Initial clinical data from the Courage Study, an ongoing first-in-human Phase 1 trial presented at the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics, showed an encouraging safety profile of FT-7051, as well as high specificity to the CBP/p300 pathway. Preliminary results reported include data as of Sept. 1, 2021, from eight men enrolled in the trial. FT-7051 was administered in 28-day cycles, with 21 days of dosing followed by seven days of no dosing. Three patients remain on study; five patients left the study (four due to disease progression and one withdrawal of consent). The adaptive trial design is intended to efficiently explore safe and efficacious doses of FT-7051. Prior to enrollment, all of the men had received diagnoses of mCRPC, castration-levels of serum testosterone and rising levels of the biomarker prostate specific antigen (PSA) after the failure of at least two lines of therapy with an approved androgen-receptor pathway inhibitor. The initial pharmacokinetic (PK) analysis of FT-7051 documented rapid absorption, which produced maximum blood concentrations within two hours. The 150 mg dose achieved drug concentrations that approached the predicted efficacious dose based on modeling with preclinical results. Skin biopsies of the men participating in the study demonstrated a reduction in H3K27AC, a marker of activity in the CBP/p300 pathway, the target of FT-7051. The majority of the treatment-emergent adverse events (TEAEs) were mild or moderate, at Grade 2 or lower, with no events leading to treatment discontinuation. One patient experienced Grade 3 hyperglycemia, which was medically managed. Following a dose reduction, this patient remained on treatment and experienced an ongoing PSA decline of greater than 50% at 12 weeks and greater than 80% at 16 weeks. Based upon these safety results, dose escalation is ongoing. The trial is continuing according to its adaptive design to further understand the safety and tolerability of FT-7051, gather data on clinical response including PSA and radiographic tumor response, as well as the assessment of secondary endpoints of clinical response.