A Systematic Review of Patients' Values, Preferences, and Expectations for the Treatment of Metastatic Prostate Cancer

Metastatic Hormone-Sensitive Prostate Cancer and Combination Treatment Outcomes: A Review

Importance

Metastatic hormone-sensitive prostate cancer is currently an incurable disease. Despite a high response rate to androgen-deprivation therapy, most cases progress to castration-resistant disease, the terminal phase. This review provides a summary of the most recent evidence for current and emerging management strategies, including treatment intensification with combinations of therapies. It also provides recommendations on applying the evidence in clinical practice to encourage appropriate treatment to improve survival outcomes among patients with metastatic hormone-sensitive prostate cancer.

Observations

Androgen-deprivation therapy is the backbone of treatment for metastatic hormone-sensitive prostate cancer; however, it is insufficient alone to provide sustained disease control and long-term survival. Addition of an androgen receptor pathway inhibitor and/or docetaxel significantly improves survival, as demonstrated by several international phase 3 randomized clinical trials. Triplet therapy composed of androgen-deprivation therapy plus an androgen receptor pathway inhibitor plus docetaxel has been shown to improve overall survival over androgen-deprivation therapy plus docetaxel. In the ARASENS trial (darolutamide), the hazard ratios (HRs) were 0.68 (95% CI, 0.57-0.80) in the overall population; 0.71 (95% CI, 0.59-0.85) and 0.61 (95% CI, 0.35-1.05) in patients with de novo and recurrent disease, respectively; 0.69 (95% CI, 0.57-0.82) and 0.72 (95% CI, 0.41-1.13) in patients with high-volume and low-volume disease, respectively; and 0.71 (95% CI, 0.58-0.86) and 0.62 (95% CI, 0.42-0.90) in patients with high-risk and low-risk disease, respectively. In the PEACE-1 trial (abiraterone acetate + prednisone), the HRs were 0.75 (95% CI, 0.59-0.95; all de novo) in the overall population and 0.72 (95% CI, 0.55-0.95) and immature in the high-volume and low-volume subgroups, respectively. In the ENZAMET trial (enzalutamide), the HRs were 0.82 (95% CI, 0.63-1.06) in the overall population; 0.73 (95% CI, 0.55-0.99) and 1.10 (95% CI, 0.65-1.86) in the de novo and recurrent subgroups, respectively; and 0.87 (95% CI, 0.66-1.17) and 0.61 (95% CI, 0.33-1.10) in the high-volume and low-volume subgroups. Combination regimens are generally well tolerated, with adverse effects dependent on the profiles of the component drugs.

Conclusions and relevance

The findings of this review show compelling evidence from phase 3 randomized clinical trials in favor of initiating triplet combination therapy for patients with metastatic hormone-sensitive prostate cancer for the best overall survival. Patients who are eligible for chemotherapy should be offered androgen-deprivation therapy plus an androgen receptor pathway inhibitor plus docetaxel, particularly patients with high-volume, high-risk, or de novo metastatic disease.

A global phase II randomized trial comparing oral taxane ModraDoc006/r to intravenous docetaxel in metastatic castration resistant prostate cancer

STUDY AIM

ModraDoc006, an oral formulation of docetaxel, is co-administered with the cytochrome P450-3A4 and P-glycoprotein inhibitor, ritonavir (r): ModraDoc006/r. The preliminary efficacy and safety of oral ModraDoc006/r was evaluated in a global randomized phase II trial and compared to the current standard chemotherapy regimen of intravenous (i.v.) docetaxel and prednisone.

METHODS

103 mCRPC patients, chemotherapy-naïve with/without abiraterone and/or enzalutamide pretreated, with adequate organ function and evaluable disease per RECIST v1.1 and PCWG3 guidelines were randomized 1:1 into two cohorts. In Cohort 1, 49 patients received docetaxel 75 mg/m2 i.v. every 3 weeks (Q3W). In Cohort 2, 52 patients received ModraDoc006/r; 21 patients with a starting dose of ModraDoc006 30 mg with ritonavir 200 mg in the morning and ModraDoc006 20 mg with ritonavir 100 mg in the evening (30-20/200-100 mg) bi-daily-once-weekly (BIDW) on Days 1, 8, and 15 of a 21-day cycle. To alleviate tolerability, the starting dose was amended to ModraDoc006/r 20-20/200-100 mg in another 31 patients. All patients received prednisone 10 mg daily. Primary endpoint was rPFS.

RESULTS

There was no significant difference in rPFS between the 2 arms (p = 0.1465). Median rPFS was 9.5 months and 11.1 months (95% CI) for ModraDoc006/r and i.v. docetaxel, respectively. Partial response was noted in 44.1% and 38.7% measurable disease patients, and 50% decline of PSA was seen in 23 (50%) and 26 (56.5%) evaluable cases treated with ModraDoc006/r and i.v. docetaxel, respectively. The safety profile of ModraDoc006/r 20-20/200-100 mg dose was significantly better than i.v. docetaxel, with mild (mostly Grade 1) gastrointestinal toxicities, no hematologic adverse events, and neuropathy and alopecia incidence of 11.5% and 25%, respectively.

CONCLUSIONS

ModraDoc006/r potentially represents a widely applicable, convenient, effective, and better tolerated oral taxane therapy option for mCRPC. Further investigation of ModraDoc006/r in a large randomized trial is warranted.

What Matters Most: The Documented Goals, Values and Motivators of Advanced Cancer Patients

BACKGROUND

Goals of care conversations are essential to delivery of goal concordant care. Infrequent and inconsistent goals of care documentation potentially limit delivery of goal concordant care.

METHODS

At Kaiser Permanente San Francisco Cancer Center, a standardized documentation template was designed and implemented to increase goals of care documentation by oncologists. The centralized, prompt-based template included value clarification of the goals and values of advanced cancer patients beyond treatment preferences. Documented conversations using the template during the initial pilot period were reviewed to characterization the clinical context in which conversations were recorded. Common goals and motivators were also identified.

RESULTS

A total of 178 advanced cancer patients had at least 1 documented conversation by a medical oncologist using the goals of care template. Oncologists consistently documented within the template goals of therapy and motivating factors in decision making. The most frequently documented goals of care were "Avoiding Pain and Suffering," "Physical Independence," and "Living as Long as Possible." The least recorded goal was "Comfort Focused Treatment Only."

CONCLUSIONS

Review of oncologist documented goals of care conversations using a prompt-based template allowed for characterization of the clinical context, therapy goals and motivators of advanced cancer patients. Communication of goals of care conversations by oncologists using a standardized prompt-based template within a centralized location has the potential to improve delivery of goal concordant care.

Treatment of primary cancer in metastatic hormone-sensitive prostate cancer

PURPOSE OF REVIEW

Recently, there has been emerging interest in the treatment of primary tumours in metastatic prostate cancer based on major trials that have provided evidence for radiation therapy and cytoreductive radical prostatectomy. Preclinical studies have further established the molecular features of metastatic disease that provide a rationale for primary treatment.

RECENT FINDINGS

Several randomised controlled trials and other prospective studies have demonstrated a benefit in overall survival, predominantly in low-volume disease. Advancements in precision medicine also offer insight into improving selection, staging and monitoring.

SUMMARY

In this review, the authors highlight and review recent data on emerging and established treatment options and shift towards personalised medicine for hormone-sensitive metastatic prostate cancer.

Treatment landscape and burden of disease in metastatic castration-resistant prostate cancer: systematic and structured literature reviews

Purpose

Metastatic castration-resistant prostate cancer (mCRPC) is a lethal disease that imposes a major burden on patients and healthcare systems. Three structured literature reviews (treatment guidelines, treatment landscape, and human/clinical/patient burden) and one systematic literature review (economic burden) were conducted to better understand the disease burden and unmet needs for patients with late-stage mCRPC, for whom optimal treatment options are unclear.

Methods

Embase®, MEDLINE®, MEDLINE® In-Process, the CENTRAL database (structured and systematic reviews), and the Centre for Reviews and Dissemination database (systematic review only) were searched for English-language records from 2009 to 2021 to identify mCRPC treatment guidelines and studies related to the treatment landscape and the humanistic/economic burden of mCRPC in adult men (aged ≥18 years) of any ethnicity.

Results

In total, six records were included for the treatment patterns review, 14 records for humanistic burden, nine records for economic burden, three records (two studies) for efficacy, and eight records for safety. Real-world treatment patterns were broadly aligned with treatment guidelines and provided no optimal treatment sequencing beyond second line other than palliative care. Current post-docetaxel treatments in mCRPC are associated with adverse events that cause relatively high rates of treatment discontinuation or disruption. The humanistic and economic burdens associated with mCRPC are high.

Conclusion

The findings highlight a lack of treatment options with novel mechanisms of action and more tolerable safety profiles that satisfy a risk-to-benefit ratio aligned with patient needs and preferences for patients with late-stage mCRPC. Treatment approaches that improve survival and health-related quality of life are needed, ideally while simultaneously reducing costs and healthcare resource utilization.

Patient and General Population Preferences Regarding the Benefits and Harms of Treatment for Metastatic Prostate Cancer: A Discrete Choice Experiment

Background

Patient preferences for treatment outcomes are important to guide decision-making in clinical practice, but little is known about the preferences of patients with metastatic hormone-sensitive prostate cancer (mHSPC).

Objective

To evaluate patient preferences regarding the attributed benefits and harms of systemic treatments for mHSPC and preference heterogeneity between individuals and specific subgroups.

Design setting and participants

We conducted an online discrete choice experiment (DCE) preference survey among 77 patients with metastatic prostate cancer (mPC) and 311 men from the general population in Switzerland between November 2021 and August 2022.

Outcome measurements and statistical analysis

We evaluated preferences and preference heterogeneity related to survival benefits and treatment-related adverse effects using mixed multinomial logit models and estimated the maximum survival time participants were willing to trade to avert specific adverse effects. We further assessed characteristics associated with different preference patterns via subgroup and latent class analyses.

Results and limitations

Patients with mPC showed an overall stronger preference for survival benefits in comparison to men from the general population (p = 0.004), with substantial preference heterogeneity between individuals within the two samples (both p < 0.001). There was no evidence of differences in preferences for men aged 45-65 yr versus ≥65 yr, patients with mPC in different disease stages or with different adverse effect experiences, or general population participants with and without experiences with cancer. Latent class analyses suggested the presence of two groups strongly preferring either survival or the absence of adverse effects, with no specific characteristic clearly associated with belonging to either group. Potential biases due to participant selection, cognitive burden, and hypothetical choice scenarios may limit the study results.

Conclusions

Given the relevant heterogeneity in participant preferences regarding the benefits and harms of treatment for mHSPC, patient preferences should be explicitly discussed during decision-making in clinical practice and reflected in clinical practice guidelines and regulatory assessment regarding treatment for mHSPC.

Patient summary

We examined the preferences (values and perceptions) of patients and men from the general population regarding the benefits and harms of treatment for metastatic prostate cancer. There were large differences between men in how they balanced the expected survival benefits and potential adverse effects. While some men strongly valued survival, others more strongly valued the absence of adverse effects. Therefore, it is important to discuss patient preferences in clinical practice.

Patient Preference Studies for Advanced Prostate Cancer Treatment Along the Medical Product Life Cycle: Systematic Literature Review

BACKGROUND

Patient preference studies can inform decision-making across all stages of the medical product life cycle (MPLC). The treatment landscape for advanced prostate cancer (APC) treatment has substantially changed in recent years. However, the most patient-relevant aspects of APC treatment remain unclear. This systematic review of patient preference studies in APC aimed to summarize the evidence on patient preferences and patient-relevant aspects of APC treatments, and to evaluate the potential contribution of existing studies to decision-making within the respective stages of the MPLC.

METHODS

We searched MEDLINE and EMBASE for studies evaluating patient preferences related to APC treatment up to October 2020. Two reviewers independently performed screening, data extraction and quality assessment in duplicate. We descriptively summarized the findings and analyzed the studies regarding their contribution within the MPLC using an analytical framework.

RESULTS

Seven quantitative preference studies were included. One study each was conducted in the marketing approval and the health technology assessment (HTA) and reimbursement stage, and five were conducted in the post-marketing stage of the MPLC. While almost all stated to inform clinical practice, the specific contributions to clinical decision-making remained unclear for almost all studies. Evaluated attributes related to benefits, harms, and other treatment-related aspects and their relative importance varied relevantly between studies. All studies were judged of high quality overall, but some methodological issues regarding sample selection and the definition of patient-relevant treatment attributes were identified.

CONCLUSION

The most patient-relevant aspects regarding the benefits and harms of APC treatment are not yet established, and it remains unclear which APC treatments are preferred by patients. Findings from this study highlight the importance of transparent reporting and discussion of study findings according to their aims and with respect to their stage within the MPLC. Future research may benefit from using the MPLC framework for analyzing or determining the aims and design of patient preference studies.