A multicenter observational study of the real-world use of docetaxel for metastatic castration-resistant prostate cancer in China

Efficacy and safety of therapies for advanced prostate cancer in Asia: Evidence from a systematic literature review

Objectives

Several therapies are available for the treatment of advanced/metastatic prostate cancer (PC). However, the systematic assessment of evidence pertaining to the use of these therapies in Asian patients is lacking.

Methods

A systematic literature review (SLR) was conducted using PubMed/Medline search in May 2021 to identify the randomized/nonrandomized controlled trials (RCTs/non-RCTs) and real-world observational studies (prospective/retrospective). Only studies published as full manuscripts in English were included if reporting the efficacy, effectiveness, and/or safety of treatments in Asian patients with advanced/metastatic PC.

Results

Of the 1,898 retrieved publications, 24 studies were included. These studies had patients with nonmetastatic castration-resistant PC (n = 2), metastatic castration-sensitive PC (n = 4), and metastatic castration-resistant PC (n = 18). Study designs included RCTs (n = 7), non-RCTs (n = 2), and real-world studies (n = 15). Treatments used in included studies were abiraterone acetate plus prednisone (AAP; n = 6), enzalutamide, lutetium-177 prostate-specific membrane antigen (177Lu-PSMA; n = 4 each), docetaxel (n = 3), apalutamide, radium-223 (n = 2 each), darolutamide, cabazitaxel, and pembrolizumab (n = 1 each). The evidence from RCTs (i.e., ARAMIS, SPARTAN, ARCHES, TITAN, LATITUDE, PREVAIL) demonstrated the clinical benefits of apalutamide, darolutamide, enzalutamide, and AAP in terms of overall, disease-free, and metastasis-free survival in Asian patients. These treatments were reported to be well tolerated, with no new safety signals identified in Asian population. The efficacy and safety profiles in Asian patients were consistent with the overall trial population. Data from real-world studies supported the effectiveness and tolerability of AAP, enzalutamide, radium-223, docetaxel, cabazitaxel, 177Lu-PSMA, and pembrolizumab in patients with advanced/metastatic PC.

Conclusions

This SLR of the Asian data on therapies for advanced PC from the pivotal and real-world studies confirms similar efficacy and safety outcomes, consistent with the results from the pivotal clinical trials. These findings will help clinicians make better treatment decisions in clinical practice for patients with advanced/metastatic PC.

Abiraterone acetate versus docetaxel for metastatic castration-resistant prostate cancer: a cohort study within the French Nationwide Claims Database

OBJECTIVES

To conduct the direct comparison of abiraterone acetate and docetaxel for first-line treatment of metastatic castration-resistant prostate cancer (mCRPC) in real-life settings.

METHODS

Data were extracted from the French nationwide claims database (SNDS) on all men aged ≥40 years starting first-line treatment with abiraterone acetate or docetaxel for mCRPC in 2014. A high-dimensional propensity score including 100 baseline characteristics was used to match patients of both groups and form two comparative cohorts. Three-year overall survival and treatment discontinuation-free survival were determined using Kaplan-Meier analysis.

RESULTS

In 2014, 2,444 patients started abiraterone for treatment of mCRPC and 1,214 started docetaxel. After trimming and matching, 716 patients were available in each group. Median overall survival tended to be longer in the abiraterone acetate cohort (23.8 months, 95% confidence interval = [21.5; 26.0]) than in the docetaxel cohort (20.3 [18.4; 21.6] months). Survival at 36 months was 34.6% for abiraterone acetate and 27.9% for docetaxel (p = 0.0027). Treatment discontinuation-free median was longer in the abiraterone acetate cohort compared to the docetaxel cohort (10.8 [10.1; 11.7] versus 7.4 [7.0; 8.0] months).

CONCLUSION

The findings underline the interest of oral abiraterone acetate over intravenous docetaxel as the first-line treatment option in mCRPC.

PSA nadir and time to PSA nadir during initial androgen deprivation therapy as prognostic factors in metastatic castration-resistance prostate cancer patients treated with docetaxel

Prostate-specific antigen nadir (nPSA) and time to nPSA (TTN) have been proved to be associated with the prognosis of prostate cancer. In this study, we explored the prognosis effect of nPSA and TTN during initial androgen deprivation therapy (ADT) in patients with metastatic castration-resistant prostate cancer (mCRPC) after treatment with docetaxel-based chemotherapy. The data of 153 mCRPC patients received docetaxel followed by ADT were retrospectively reviewed. Multivariate Cox regression analysis demonstrated that TTN (overall survival (OS): Hazard ratio [HR] 0.096, 95% confidence interval [CI] 0.045-0.206, p < .001; progression-free survival (PFS): HR 0.128, 95% CI 0.078-0.211, p < .001) and nPSA (OS: HR 2.849, 95% CI 1.318-6.157, p = .008; PFS: HR 1.573, 95% CI 1.008-2.454, p = .046) acted as independent predictors of chemotherapy prognosis. Kaplan-Meier analysis showed that patients with nPSA ≥ 0.2 ng/ml or TTN < 6.5 months had shorter OS and PFS. These results suggest that TTN and nPSA during ADT can affect the prognosis of docetaxel-based chemotherapy prognosis post-castration resistance in patients with mCRPC, and higher nPSA and shorter TTN lead to poor chemotherapy prognosis. What is more, TTN has a greater impact during ADT on the prognosis of chemotherapy than nPSA.

Radium-223 in Asian patients with castration-resistant prostate cancer with symptomatic bone metastases: A single-arm phase 3 study

Aim

Radium‐223, a targeted alpha therapy, is approved widely for the treatment of patients with metastatic castrate‐resistant prostate cancer, based on a pivotal phase 3 study in predominantly white patients. We investigated the efficacy and safety of radium‐223 in Asian patients with castrate‐resistant prostate cancer and metastatic bone disease.

Methods

This multicenter, prospective, single‐arm, open‐label phase 3 trial evaluated the efficacy and safety of the standard radium‐223 regimen (55 kBq/kg every 4 weeks for six cycles) in patients from Asian countries. The primary endpoints were the safety and overall survival.

Results

A total of 226 patients were enrolled and received at least one dose of radium‐223. Median overall survival was 14.0 months (95% confidence interval [CI], 11.2–17.4). Median time to total alkaline phosphatase and prostate‐specific antigen progression were 7.5 (95% CI, 6.8–7.7) and 3.6 (95% CI, 3.1–3.7) months, respectively. Median skeletal‐related event‐free survival was 26.0 months (95% CI, 12.6–not reached). Grade ≥3 treatment‐emergent adverse events were reported in 103 (46%) of 226 patients, with anemia being the most common event (34 [15%] patients). Grade ≥3 drug‐related treatment‐emergent adverse events occurred in 39 (17%) of 226 patients. Serious treatment‐emergent adverse events were reported in 65 (29%) of 226 patients. Seven (3%) patients had an adverse event leading to death; none were considered to be related to radium‐223.

Conclusion

The results of this study support the use of the standard radium‐223 regimen for the treatment of Asian patients with castrate‐resistant prostate cancer and symptomatic bone metastases.

A multicenter observational study of the real-world use of docetaxel for metastatic castration-resistant prostate cancer in China

Aim

To investigate the use of docetaxel for the treatment of metastatic castration‐resistant prostate cancer (mCRPC) in real‐world clinical practice in China.

Methods

This single‐arm, prospective, observational study was conducted at 32 study centers in China and included male patients aged ≥18 years with histologically confirmed prostate cancer who received ≥1 dose of docetaxel following failure of hormonal therapy (disease progression with serum testosterone <50 ng/dL). The primary aim was to investigate patterns of docetaxel treatment.

Results

Overall 403 patients were included between August 2011 and June 2016; patients initiated docetaxel after failure of first‐ (42.2% [170]), second‐ (31.0% [125]) and ≥third‐line (12.7% [51]) hormonal therapy, estramustine (11.4% [46]) or other (2.7% [11]). The planned cycles of docetaxel therapy were completed by 30.8% of patients, and the mean (SD) number of cycles received was 4.4 (2.86). Median overall survival (mOS) was 22.4 (95% CI, 20.4–25.8) months and the prostate‐specific antigen (PSA) response rate in patients with available data was 70.9% (168/237), with no differences in mOS and PSA response rates between treatment settings. Subgroup analysis revealed higher mOS in patients without visceral metastasis versus those with such metastases (22.9 vs. 17.4 months; P = 0.022). No new safety signals were observed and the most common adverse events associated with docetaxel were granulocytopenia (5%) and leukopenia (4.5%).

Conclusion

Data from this study showed that around three‐quarters of Chinese patients with mCRPC treated with docetaxel initiated treatment following first‐ or second‐line hormonal therapy and no new safety signals were observed.