AR T878A

Our study revealed dynamic shifts in genetic mutations in pts with mCRPC following ARSi, PARPi and taxanes. Additionally, we highlight the prognostic significant of ctDNA burden in mCRPC. These data can help inform personalized sequential tx strategies for pts with mCRPC.

AR mutations have implications for clinical decision making and drug development in patients treated with abiraterone and/or enzalutamide. >1n (%).

Commonly found mutations include L702H, W742C, H875Y, F877L and T878A, while the F877L mutation can convert second-generation antagonists such as enzalutamide and apalutamide into agonists. However, pruxelutamide, another second-generation AR antagonist, has no agonist activity with the F877L and F877L/T878A mutants and instead maintains its inhibitory activity against them...Additional structural studies suggest that both the L702H and F877L mutations are important for conformational changes. This structural variability in the AR LBD could affect ligand binding as well as the resistance to antagonists.

The androgen deprivation therapy (ADT) alone and its combination with hormone therapy that block AR signaling (e.g., enzalutamide or abiraterone) are effective treatments for advanced prostate cancer. No animal was found dead or moribund and no test article-related changes in clinical signs,body weights, food consumption, ophthalmologic examinations, clinical pathology parameters, sperm analysis, urinalysis, organ weights, histopathology. In conclusion, HSK38008 is a promising oral AR-V7 degrader with better efficacy than enzalutamide and ARV-110 in AR and AR-V7 positive, and potential AR mutants mCRPC.

In this large database, the overall detection rate of activating AR-LBD mutations in men with mCRPC undergoing ctDNA analysis was 21%, and increased with prior use of 2nd generation ARPi (abiraterone and enzalutamide). Men with AR-LBD mutations were more likely to harbor other alterations relevant to tumor progression. These findings inform on the ctDNA prevalence and impact of AR-LBD mutations in a real-world dataset of mCRPC.

Patients enrolled in the cohort expansion must have received 1–3 prior NHAs (eg, abiraterone or enzalutamide) and ≤2 prior chemotherapy regimens. Enrollment in the phase 2 expansion study is ongoing. Clinical trial information: NCT05067140.

Two early phase trials investigating CYP11A1 inhibitors - CYPIDES (ODM208, NCT03436485) and STESIDES (ODM209, NCT03878823) - recruited mCRPC patients with and without pre-specified AR LBD mutation...Overall, 212 (78%), 202 (74%), and 240 (88%) patients had received previous abiraterone, enzalutamide, and docetaxel respectively... AR LBD mutations were detected in ctDNA in 25% of men with advanced mCRPC treated with at least one ARSI. Their incidence was associated with a longer duration of treatment with enzalutamide and a longer time from CRPC and prostate cancer diagnosis. >

Computational modelling revealed that helix 12 of AR undergoes a characteristic shift upon VPC14368 binding causing the agonistic behaviour. Based on the obtained structural data we then designed derivatives of VPC14368 to successfully eliminate the cross-reactivity towards the AR ABS, while maintaining significant anti-AR DBD potency.

The proteins' motion and FEL further validated the aforementioned findings where the wild type reported different dynamic features than the mutant complexes. In conclusion, this study provides a structural basis for the resistance to Enzalutamide, which can be used to design novel effective drugs using structure-based and rationale approaches.

Hormonal therapies including androgen deprivation therapy and androgen receptor (AR) pathway inhibitors such as abiraterone and enzalutamide have been widely used to treat advanced prostate cancer. Currently, precision medicine utilizing genetic and genomic data to choose suitable treatment for the patient is becoming to play an increasingly important role in clinical practice for prostate cancer management. Therefore, monitoring the AR mutation status is a promising approach for providing precision medicine in prostate cancer, which would be implemented through the development of clinically available testing modalities for AR mutations using liquid biopsy.

No abstract available

AR mutations in post-ARTA group were seen at similar rates regardless of prior docetaxel exposure (14.3% vs 18.0%, p = 0.46) and following first abiraterone vs enzalutamide/apalutamide exposure (48.6% vs 48.3%, p = 1.0). AR mutations, unlike amplifications, were associated with shorter TTP on abiraterone. Genomic testing should be considered before second line ARTA.

In phase 1, pts with mCRPC and disease progression after =2 prior therapies (enzalutamide and/or abiraterone required) received ARV-110 orally once or twice daily (QD or BID) in sequential cohorts (3 + 3 dose escalation design). ARV-110, a novel AR protein degrader, demonstrates clinical activity in a post-NHA, heavily pretreated mCRPC pt population, with greatest PSA50 activity and RECIST responses in pts with AR T878 and/or H875 mutations, likely representing a particularly ARV-110–sensitive population. ARV-110 merits further investigation in pts with mCRPC.

In this analysis of CRPC patients who were responders and non-responders to 400 mg testosterone cypionate q 3-4 weeks (post-abiraterone and/or enzalutamide), only AR amplifications in ctDNA were predictive of response. In all measured patients, the degree of AR amplification in the ctDNA diminished after testosterone injections.

In phase 1, pts with mCRPC and disease progression after =2 prior therapies (enzalutamide and/or abiraterone required) received ARV-110 orally once or twice daily (QD or BID) in sequential cohorts (3 + 3 dose escalation design). ARV-110, a novel AR protein degrader, demonstrates clinical activity in a post-NHA, heavily pretreated mCRPC pt population, with greatest PSA50 activity and RECIST responses in pts with AR T878 and/or H875 mutations, likely representing a particularly ARV-110–sensitive population. ARV-110 merits further investigation in pts with mCRPC.

This study establishes the technical feasibility of analyzing structural rearrangements, mutations, and copy number variants in AR and other CRPC genes using two different sources of DNA from a single blood sample. Paired CTC DNA and cfDNA analysis may have utility for capturing the heterogeneity of genetic alterations in CRPC patients.

Furthermore, combining chemical V-ATPase inhibition with the AR antagonist enzalutamide resulted in a greater reduction in AR downstream target expression than enzalutamide alone in LNCaP cells...Overall, these results indicate that V-ATPase dysregulation is directly linked to both hormone responsive and CRPC via impact on AR function. In particular, V-ATPase inhibition can reduce AR signaling regardless of mutant AR expression.

We were also able to identify the androgen receptor (AR) point mutation T878A from 7.5 mL blood samples spiked with 50 LNCaP cells using RT-PCR and Sanger sequencing. Finally, CTCs were detected in 8 out of 8 samples from patients diagnosed with metastatic prostate cancer (mean ± SEM = 21 ± 2.957 CTCs/mL, median = 21 CTCs/mL), demonstrating the potential clinical utility of this device.

Abi/prednisone + onvansertib is well tolerated and AE’s are effectively managed. Across arms A and B, 8/26 evaluable patients (31%) achieved the primary endpoint, 14/26 with SD (54%). Three of 7 patients harboring AR alterations associated with abi resistance achieved DC.

AR amplification was detected in the majority of CRPC samples analysed using either cell-free DNA (cfDNA) or exosome isolation kits (80%). We demonstrated that selective isolation of a subset of circulating exosomes enriched for tumor origin, rather than analysis of total plasma exosomes, or total plasma nucleic acids, increases sensitivity and specificity for the detection of specific alterations.

The goal was to characterize androgen receptor gene (AR) amplifications and mutations detected in circulating tumor DNA (ctDNA) from patients with prostate cancer in relation to non-AR gene alterations detected in the ctDNA landscape. The study included 892 patients with prostate cancer with AR alterations in ctDNA. AR alterations were significantly associated with other gene alterations detected in ctDNA. The common AR mutations found are linked to resistance to abiraterone, enzalutamide, or bicalutamide. Characterization of the circulating AR landscape and gene alterations provides potential additional insight into the somatic genetic heterogeneity of advanced prostate cancer.