Emergence of triplet therapy for metastatic castration-sensitive prostate cancer: An updated systematic review and network meta-analysis

Apalutamide in Metastatic Castration-sensitive Prostate Cancer: Results from the Multicenter Real-world ARON-3 Study

BACKGROUND AND OBJECTIVE

Apalutamide (APA) is a treatment for metastatic castration-sensitive prostate cancer (mCSPC). In the ARON-3 study we investigated real-world experiences with APA treatment for mCSPC.

METHODS

We retrospectively assessed real-world clinical outcomes for patients with mCSPC treated with APA in the ARON-3 study. Overall survival (OS) was calculated from APA initiation to death from any cause. PSA90 was defined as a prostate-specific antigen decline of ≥90% from baseline, and PSA0.2 as achievement of a PSA level ≤0.2 ng/ml. Data for adverse events were retrospectively collected from electronic and paper charts and categorized according to Common Terminology Criteria for Adverse Events v5.0.

KEY FINDINGS AND LIMITATIONS

We included 531 patients with mCSPC treated with APA. High-volume disease was reported for 214 patients (40%), and 56 (11%) had visceral metastases. Median OS was not reached. PSA90 was experienced by 461 patients (87%) and PSA0.2 by 368 (69%). Median OS was significantly longer for patients with PSA90 or PSA0.2 than for subjects without these responses (p < 0.001). The incidence of grade 3-4 fatigue was higher among elderly patients (≥80 yr) than among younger patients (19% vs 5%), but the incidence of other adverse events was comparable between the age groups.

CONCLUSIONS AND CLINICAL IMPLICATIONS

APA is an effective and tolerable treatment for mCSPC in the real-world setting.

PATIENT SUMMARY

The ARON-3 project collects data for patients with prostate cancer treated in multiple centers worldwide to assess outcomes in the real-world setting. We analyzed data for patients with metastatic hormone-sensitive prostate cancer receiving apalutamide. Our results show that apalutamide is a safe and effective drug in the real-world setting as well as in clinical trials.

Patient-reported Quality of Life and Survival Outcomes in Prostate Cancer: Analysis of the ECOG-ACRIN E3805 Chemohormonal Androgen Ablation Randomized Trial (CHAARTED)

BACKGROUND

Chemohormonal therapy with androgen deprivation therapy and docetaxel (ADT + D) improves overall survival (OS) and quality of life (QOL) at 12 mo versus androgen deprivation therapy (ADT) alone in men with metastatic hormone-sensitive prostate cancer (mHSPC). However, the prognostic role of QOL is unknown in this population.

OBJECTIVE

To study the relationship between QOL, disease characteristics, and OS in men with mHSPC.

DESIGN, SETTING, AND PARTICIPANTS

In this exploratory post hoc analysis, 790 patients with mHSPC completed the QOL instruments Functional Assessment of Cancer Therapy-Prostate (FACT-P), Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F), and Brief Pain Inventory (BPI).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Log-rank test and Cox proportional hazard models tested the association between QOL and OS by clinical and disease characteristics.

RESULTS AND LIMITATIONS

Baseline higher FACT-P trended toward improved survival after accounting for clinical variables (hazard ratio [HR] 0.80 [0.62, 1.04], p = 0.09), while higher 3-mo FACT-P was independently associated with better survival (HR 0.76 [0.58, 1.0], p = 0.05). Patients with the poorest QOL (bottom quartile) at baseline and 3 mo had longer survival if they received ADT + D rather than ADT alone (median OS 45.2 vs 34.4 mo, HR 0.75 [0.53, 1.05], p = 0.09, and 48.3 vs 29.3 mo, HR 0.69 [0.48, 0.99], p = 0.05 respectively). In contrast, patients with the best QOL (top quartile) at baseline and 3 mo had comparable survival irrespective of whether or not docetaxel was added (median OS 72.1 vs 51.7 mo, HR 0.92 [0.63, 1.36], p = 0.69, and 69.9 vs 68.9 mo, HR 1.11 [0.73, 1.67], p = 0.63, respectively). Survival was linked with baseline FACIT-F (HR 0.76 [0.57, 1.0], p = 0.05), but not BPI (HR 0.98 [0.75, 1.28], p = 0.90).

CONCLUSIONS

Three-month QOL had a stronger independent association with survival. The most symptomatic patients had longer survival with the addition of docetaxel; conversely, the least symptomatic patients did not appear to benefit. Consideration of QOL may enhance decision-making and patient selection when choosing chemohormonal treatment in mHSPC.

PATIENT SUMMARY

Quality of life independently forecasted the survival of men with metastatic hormone-sensitive prostate cancer in the CHAARTED study. Close tracking of quality of life could help patients and clinicians make decisions about the appropriate treatment in this setting.

Recommendations on the treatment of metastatic hormone-sensitive prostate cancer: Patient selection

The standard treatment for metastatic hormone-sensitive prostate cancer (mHSPC) is now a combination of androgen deprivation therapy plus an androgen receptor-targeted therapy (abiraterone, apalutamide, enzalutamide or darolutamide), with or without chemotherapy (docetaxel). The selection of suitable patients for each therapeutic approach has become a determining factor to ensure efficacy and minimize side effects. This article combines recent clinical evidence with the accumulated experience of experts in medical oncology, radiation oncology and urology, to provide a comprehensive view and therapeutic recommendations for mHSPC.

Cost Effectiveness of Systemic Treatment Intensification for Metastatic Hormone-sensitive Prostate Cancer: Is Triplet Therapy Cost Effective?

BACKGROUND AND OBJECTIVE

There has been a shift toward systemic treatment intensification for men with metastatic hormone-sensitive prostate cancer (mHSPC). Recent trials have demonstrated the efficacy of triplet therapy with an androgen receptor signalling inhibitor (ARSI), docetaxel, and androgen deprivation therapy (ADT). However, ARSI treatment is expensive. The objective was to determine the cost effectiveness of current treatments strategies for men with mHSPC.

METHODS

We developed a Markov state-transition model to simulate outcomes for men with newly diagnosed mHSPC. For the simulation, patients were entered in the model in the mHSPC disease state before progressing to castration-resistant disease and finally dying from prostate cancer. Costs were calculated from a USA health sector perspective in 2022 US dollars. Deterministic and probabilistic sensitivity analyses were conducted to account for uncertainty in the parameter estimates. We also performed scenario analyses for costs in the UK and Australian health sectors.

KEY FINDINGS AND LIMITATIONS

Treatment intensification with doublet and triplet therapy resulted in an improvement in quality-adjusted survival for all strategies in comparison to ADT monotherapy. However, only docetaxel doublet therapy was cost effective at standard thresholds, with an incremental cost-effectiveness ratio of $13 647. The cost of ARSIs needed to be discounted by 47-70% before they were cost effective. Only medication costs impacted the model results. If the generic price for abiraterone acetate is used, then triplet therapy with abiraterone is the best-value option. Similar results were obtained for analyses for the UK and Australian health sectors.

CONCLUSIONS AND CLINICAL IMPLICATIONS

Treatment intensification with ARSIs in men with mHSPC results in better quality-adjusted survival but is not cost effective according to standard thresholds. The costs of these medications would need to be heavily discounted before they are cost effective. The cost of generic ARSIs, once available, would render these strategies cost effective.

PATIENT SUMMARY

This report examines whether increasing the number of systemic drugs used to treat a patient's metastatic hormone-sensitive prostate cancer is cost effective for the health care system. We found that the additional cost of triplet therapy does not justify the increase in patient benefit.

Incidence of postoperative complications is underestimated if outcome data are recorded by interns and first year residents in a low volume hospital setting

The aim of this study is to evaluate the accuracy of outcome reporting after elective visceral surgery in a low volume district hospital. Outcome measurement as well as transparent reporting of surgical complications becomes more and more important. In the future, financial and personal resources may be distributed due to reported quality and thus, it is in the main interest of healthcare providers that outcome data are accurately collected. Between 10/2020 and 09/2021 postoperative complications during the hospitalisation were recorded using the Clavien-Dindo classification (CDC) and comprehensive complication index by residents of a surgical department in a district hospital. After one year of prospective data collection, data were retrospectively analyzed and re-evaluated for accuracy by senior consultant surgeons. In 575 patients undergoing elective general or visceral surgery interns and residents reported an overall rate of patients with complications of 7.3% (n = 42) during the hospitalization phase, whereas a rate of 18.3% (n = 105) was revealed after retrospective analysis by senior consultant surgeons. Thus, residents failed to report patients with postoperative complications in 60% of cases (63/105). In the 42 cases, in which complications were initially reported, the grading of complications was correct only in 33.3% of cases (n = 14). Complication grades that were most missed were CDC grade I and II. Quality of outcome measurement in a district hospital is poor if done by unexperienced residents and significantly underestimates the true complication rate. Outcome measurement must be done or supervised by experienced surgeons to ensure correct and reliable outcome data.

Is There an Opportunity to De-Escalate Treatments in Selected Patients with Metastatic Hormone-Sensitive Prostate Cancer?

The treatment landscape for metastatic hormone-sensitive prostate cancer continues to evolve, with systemic treatment being the mainstay of current treatment. Prognostic and predictive factors such as tumour volume and disease presentation have been studied to assess responses to different treatments. Intensification and de-escalation strategies arouse great interest, so several trials are being developed to further personalize the therapy in these populations. Is there an optimal sequence and a possible option to de-intensify treatment in selected patients with a favourable profile? This and other goals will be the subject of this review.

[Systemic therapy for mHSPC: doublet or triplet therapy - who, when and how?]

At present, androgen deprivation therapy (ADT) as monotherapy for metastatic hormone-sensitive prostate cancer (mHSPC) should be an exception. The new standard of care is a doublet combination consisting of ADT + a new hormonal agent (NHA) or ADT + chemotherapy. Contemporary investigations even recommend a triplet therapy consisting of ADT + NHA + chemotherapy for selected mHSPC patients. The current evolution of mHSPC therapy demands a pretherapeutic classification of mHSPC: "low" vs. "high risk", "low" vs. "high volume" and synchronous vs. metachronous mHSPC. Additionally, attention should be paid to the drug specific side effects and especially whether the patient is fit for chemotherapy. This article gives a concise overview of the key clinical trials, current guideline recommendations and drug approvals for Germany.

[Androgen deprivation therapy plus chemotherapy ± androgen receptor-targeting agents for metastatic hormone-sensitive prostate cancer]

BACKGROUND

Although androgen deprivation therapy (ADT) alone has been the standard of care (SOC) in the treatment of metastatic hormone-sensitive prostate cancer (mHSPC) for decades, combination therapies of novel hormone therapy (androgen receptor-targeting agents [ARTA]) or docetaxel chemotherapy have more recently replaced single ADT treatment. In addition, data for triplet therapies with ADT plus ARTA (abiraterone/darolutamide) and docetaxel chemotherapy are now available.

OBJECTIVES

The present review addresses the question which therapy is suitable for which mHSPC patient. Who benefits from doublet therapy and which patient from triplet therapy? Which side effects can be expected?

RESULTS

Triplet therapy consisting of ADT + docetaxel + abiraterone/darolutamide resulted in a significantly longer overall survival compared to therapy consisting of ADT + docetaxel of all mHSPC (ARASENS) and primary metastatic high-volume (PEACE-1) mHSPC patients. In the setting of high-volume mHSPC, prolonged overall survival is seen for the specific triplet combination of ADT + docetaxel + abiraterone. In the low-volume mHSPC setting, only an extended progression-free survival but not overall survival was observed. Data regarding the classification of high- vs. low-volume mHSPC for the triplet therapy consisting of darolutamide are currently not available. Side effects with triplet therapies are almost comparable with those of doublet therapies and relate to typical chemotherapy-associated (neutropenia) and ARTA-specific side effects (abiraterone).

CONCLUSION

ADT alone or ADT + docetaxel should no longer play a role in first-line therapy for mHSPC. Accordingly, therapy consisting of ADT + ARTA or ADT + ARTA + docetaxel represents the current primary treatment option pending further data and regarding patient-specific characteristics (age, ECOG status, metastatic burden, primary/secondary metastatic disease).