Treatment Landscape of Nonmetastatic Castration-Resistant Prostate Cancer: A Window of Opportunity

Physician preferences for nonmetastatic castration-resistant prostate cancer treatment in China

Introduction

The treatment preferences of Chinese physicians who treat nonmetastatic castration-resistant prostate cancer (nmCRPC) and how they weigh the benefits and risks of nmCRPC treatment are still unknown. This study aimed to evaluate Chinese physicians' benefit-risk treatment preferences for nmCRPC and assist in setting nmCRPC treatment goals.

Methods

A paper-based discrete choice experiment (DCE) survey was administered to 80 nmCRPC-treating physicians. DCE responses were analyzed to produce the preference weight and the relative importance score for each attribute level. The marginal rate of substitution (MRS) was used to quantify the amount of overall survival (OS) physicians were willing to trade for a reduction in treatment-related adverse events (AEs). We further conducted the exploratory analysis, stratifying physicians from 5 perspectives into different subgroups and examining the treatment preferences and OS trade-off in each subgroup.

Results

In terms of efficacy attributes, physicians placed greater emphasis on OS than time to pain progression. With regard to safety attributes, serious fracture was perceived as the most important AE by physicians, followed by serious fall, cognitive problems, skin rash, and fatigue. In the exploratory analysis, we found generally that physicians with less clinical practice experience and those from more economically developed regions placed more emphasis on AEs and were willing to give up more of their patients' OS to reduce the risk of AEs.

Conclusion

Physicians from mainland China value the importance of minimizing treatment-related AEs when considering different treatment options for patients with nmCRPC, and they are willing to trade a substantial amount of OS to avoid AEs.

A multidisciplinary approach to address unmet needs in the management of patients with non-metastatic castration-resistant prostate cancer

BACKGROUND

With the availability of second-generation androgen receptor inhibitors (SGARIs), the treatment landscape has changed dramatically for patients with nonmetastatic castration-resistant prostate cancer (nmCRPC). In clinical trials, the SGARIs (apalutamide, enzalutamide, darolutamide) increased metastasis-free survival (MFS), overall survival (OS), and patient quality of life compared to placebo. These drugs were subsequently integrated into nmCRPC clinical practice guidelines. With advances in radiographic imaging, disease assessment, and patient monitoring, nmCRPC strategies are evolving to address limitations related to tracking disease progression using prostate-specific antigen (PSA) kinetics.

METHODS

A panel of 10 multidisciplinary experts in prostate cancer conducted reviews and discussions of unmet needs in the management and monitoring of patients with nmCRPC in order to develop consensus recommendations.

RESULTS

Across the SGARI literature, patient MFS and OS are generally comparable for all treatments, but important distinctions exist regarding short- and long-term drug safety profiles and drug-drug interactions. With respect to disease monitoring, a substantial proportion of patients using SGARIs may experience disease progression without rising PSA levels, suggesting a need for enhanced radiographic imaging in addition to PSA monitoring. Recent data also indicate that novel prostate-specific membrane antigen positron emission tomography radiotracers provide enhanced accuracy for disease detection, as compared to conventional imaging.

CONCLUSIONS

Clinical decision-making in nmCRPC has become more complex, with new opportunities to apply precision medicine to patient care. Multidisciplinary teams can ensure that patients with nmCRPC receive optimal and individualized disease management.

Electronic effect-dependent intramolecular non-covalent interactions on the activity of 4,4-dimethylimidazolidin-2-one pharmacophore-based androgen receptor antagonists

Because androgen receptor (AR) signalling is important for the development and progression of prostate cancer (PC), AR antagonists are utilized in clinical practices to treat PC and are referred to as androgen deprivation therapy (ADT). However, continued administration of AR antagonists often results in the development of resistance, known as castration-resistant prostate cancer (CRPC). Despite castration, it has been demonstrated that AR signalling continues to be fundamental to tumour growth. In this regard, a series of readily synthesizable 4,4-dimethylimidazolidine-2-one pharmacophore-based AR antagonists (FAR01-FAR11) were designed and synthesized. Androgen-dependent LNCaP PC cell line was used to test the AR-antagonist activity of these compounds in vitro and compared with the U.S. Food and Drug Administration (FDA) approved second-generation enzalutamide. In our previous work, rigid thiohydantoin pharmacophore in enzalutamide is replaced by the flexible 4,4-dimethylimidazolidin-2-one. In order to improve the flexibility further, one methylene group is introduced between the pharmacophore and one of the aromatic ring. Despite the fact that the amide functional group is a crucial characteristic for building AR antagonists, this class of molecules lacks one. FAR06 has the exact same activity as enzalutamide (IC₅₀ : 0.782 μM) with an IC₅₀ value of 0.801 μM among the series of compounds.

Disability weights for castration-resistant prostate cancer: an empirical investigation

Introduction

Health state valuation and diagnostic-therapeutic pathways at the junction between non-metastatic and metastatic castration-resistant prostate cancer (CRPC) are not well documented. We aimed at: (i) estimating the disability weights (DWs) for health states across a continuum of disease from asymptomatic non-metastatic (nmCRPC) to symptomatic metastatic state (mCRPC); (ii) mapping the diagnostic-therapeutic pathway of nmCRPC in Italy.

Methods

Structured qualitative interviews were performed with clinical experts to gather information on nmCRPC clinical pathway. An online survey was administered to clinical experts to estimate DWs for four CRPC health states defined from interviews and literature review (i.e., nmCRPC, asymptomatic mCRPC, symptomatic mCRPC, mCRPC in progression during or after chemotherapy). Clinicians' preferences for health states were elicited using the Person-Trade-Off (PTO) and Visual Analogue Scale (VAS) methods. DWs associated with each health state, from 0 (best imaginable health state) and 1 (worst imaginable health state), were estimated.

Results

We found that the management of nmCRPC is heterogeneous across Italian regions and hospitals, especially with respect to diagnostic imaging techniques. DWs for PTO ranged from 0.415 (95% confidence interval [CI] 0.208-0.623) in nmCRPC to 0.740 (95% CI 0.560-0.920) in mCRPC, in progression during or after chemotherapy. DWs for VAS ranged between 0.246 (95% CI 0.131-0.361) in nmCRPC to 0.689 (95% CI 0.583-0.795) in mCRPC, in progression during or after chemotherapy.

Conclusions

Estimated DWs suggest that delaying transition to a metastatic state might ease the disease burden at both patient and societal levels.