Association between age and efficacy of combination systemic therapies in patients with metastatic hormone-sensitive prostate cancer: a systematic review and meta-analysis

Real-world evidence of triplet therapy efficacy in patients with metastatic castration-sensitive prostate cancer: a Japanese multicenter study

BACKGROUND

Two randomized trials demonstrated that the survival benefits afforded by triplet therapy were greater than those of doublet therapy, thus changing the treatment paradigm for metastatic castration-sensitive prostate cancer (mCSPC). This is the first study to assess the real-world use, performance, and safety of triplet therapy in Japanese patients.

METHODS

This retrospective multicenter study included 45 consecutive mCSPC patients who received triplet therapy composed of androgen deprivation therapy (ADT), docetaxel, and darolutamide between January 2023 and June 2024. Baseline patient characteristics and their clinical parameters during triplet therapy were collected. Adverse events (AEs) were graded using Common Terminology Criteria for Adverse Events version 5.0, and imaging responses were evaluated following the RECIST criteria. The prostate-specific antigen (PSA) nadir was defined as the lowest PSA value during follow-up, and the PSA decrease was the initial PSA value minus the PSA nadir.

RESULTS

The median patient age was 70 years and the median follow-up duration was 10 months. High-volume disease was present in 82.2% of patients. Concurrent administration of docetaxel and darolutamide was scheduled for 22.2% of cases. The incidence of any AE was 86.7%, with 55.5% of patients experiencing grade 3-4 AEs. Neutropenia was common, but prophylactic granulocyte colony-stimulating factor (G-CSF) significantly reduced the incidence of neutropenia of grade 3 or higher. Febrile neutropenia occurred in four patients (8.9%); these patients had not received prophylactic G-CSF. A decline in PSA of 90% was observed in 95.6% of patients, and an imaging response was seen in 97.8%.

CONCLUSIONS

Triplet therapy with ADT, darolutamide, and docetaxel was highly efficacious and tolerable in Japanese mCSPC patients, particularly those with high-volume disease. Prophylactic G-CSF prescription is crucial to manage neutropenia effectively. Further studies with longer follow-ups are needed to confirm these findings and explore the long-term outcomes.

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.

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.

Real-World Evidence of Triplet Therapy in Metastatic Hormone-Sensitive Prostate Cancer: An Austrian Multicenter Study

INTRODUCTION

Two randomized trials demonstrated a survival benefit of triplet therapy (androgen deprivation therapy [ADT]) plus androgen receptor pathway inhibitor [ARPI] plus docetaxel) over doublet therapy (ADT plus docetaxel), thus changing treatment strategies in metastatic hormonesensitive prostate cancer (mHSPC).

PATIENTS AND METHODS

We conducted the first real-world analysis comprising 97 mHSPC patients from 16 Austrian medical centers, among them 79.4% of patients received abiraterone and 17.5% darolutamide treatment. Baseline characteristics and clinical parameters during triplet therapy were documented. Mann-Whitney U test for continuous or X²-test for categorical variables was used. Variables on progression were tested using logistic regression analysis and tabulated as hazard ratios (HR), 95% confidence interval (CI).

RESULTS

Of 83.5% patients with synchronous and 16.5% with metachronous disease were included. 83.5% had high-volume disease diagnosed by conventional imaging (48.9%) or PSMA PET-CT (51.1%). While docetaxel and ARPI were administered consistent with pivotal trials, prednisolone, prophylactic gCSF and osteoprotective agents were not applied guideline conform in 32.5%, 37%, and 24.3% of patients, respectively. Importantly, a nonsimultaneous onset of chemotherapy and ARPI, performed in 44.3% of patients, was associated with significantly worse treatment response (P = .015, HR 0.245). Starting ARPI before chemotherapy was associated with significantly higher probability for progression (P = .023, HR 15.781) than vice versa. Strikingly, 15.6% (abiraterone) and 25.5% (darolutamide) low-volume patients as well as 14.4% (abiraterone) and 17.6% (darolutamide) metachronous patients received triplet therapy. Adverse events (AE) occurred in 61.9% with grade 3 to 5 in 15% of patient without age-related differences. All patients achieved a PSA decline of 99% and imaging response was confirmed in 88% of abiraterone and 75% of darolutamide patients.

CONCLUSIONS

Triplet therapy arrived in clinical practice primarily for synchronous high-volume mHSPC. Regardless of selected therapy regimen, treatment is highly effective and tolerable. Preferably therapy should be administered simultaneously, however if not possible, chemotherapy should be started first.

Digital droplet immunoassay based on a microfluidic chip with magnetic beads for the detection of prostate-specific antigen

Sensitive biomarker detection techniques are beneficial for both disease diagnosis and postoperative examinations. In this study, we report an integrated microfluidic chip designed for the immunodetection of prostate-specific antigens (PSAs). The microfluidic chip is based on the three-dimensional structure of quartz capillaries. The outlet channel extends to 1.8 cm, effectively facilitating the generation of uniform droplets ranging in size from 3 to 50 μm. Furthermore, we successfully immobilized the captured antibodies onto the surface of magnetic beads using an activator, and we constructed an immunosandwich complex by employing biotinylated antibodies. A key feature of this microfluidic chip is its integration of microfluidic droplet technology advantages, such as high-throughput parallelism, enzymatic signal amplification, and small droplet size. This integration results in an exceptionally sensitive PSA detection capability, with the detection limit reduced to 7.00 ± 0.62 pg/mL.

Optimal combination therapy for metastatic hormone-sensitive prostate cancer: new evidence, challenges and unanswered questions

PURPOSE OF REVIEW

To evaluate the evidence supporting treatment intensification in mHSPC, with a focus on possible indications for treatment in each clinical setting.

RECENT FINDINGS

There is a growing armamentarium of treatment options for patients with metastatic hormone-sensitive prostate cancer (mHSPC). These include combinations of treatments such as androgen deprivation therapy (ADT), docetaxel, and new antiandrogenic therapies. Treatment intensification with chemotherapy or newer hormonal agents may improve patient's oncologic outcomes, but it can also come with additional toxicities and costs. Therefore, we need to take into account individual patient factors and preferences when deciding on the optimal combination therapy. Additionally, ongoing research is needed to identify biomarkers and new image techniques that can predict response to treatment and identify the best candidate for each treatment.

SUMMARY

Challenges and unanswered questions regarding treatment intensification and de-intensification are still present. Further studies are still needed to identify which patients would benefit most from this approach to improve quality of life without compromising overall survival outcomes.