e17103 Background: Apalutamide (APA) combined with androgen deprivation therapy (ADT) is the standard care for mHSPC and is associated with significant survival benefits. Given limited data from Chinese patients (pts), this study aimed to conduct the largest observational investigation to date to assess the real-world effectiveness and safety of APA plus ADT in Chinese pts with mHSPC, with a focus on prostate-specific antigen (PSA) decline and disease progression. Methods: This retrospective, multicenter observational study enrolled adult pts with mHSPC who initiated on APA plus ADT between 1 Jan 2022 and 31 May 2024 (index date), with follow-up through 31 May 2025, utilizing data from chart review. The observation period for each pt spanned from the index date to loss to follow-up, death, or 1-year follow-up. The primary endpoint was the proportion of pts achieving PSA≤0.2 ng/mL (PSA0.2) at Month (M) 3. Other endpoints included proportion of pts achieving a decrease in PSA ≥50% or ≥90% (PSA50/90), PSA progression, clinical and radiographic disease progression events within 12 mo. The number and proportion of pts achieving PSA0.2 or PSA50/90 along with their 95% confidence intervals (CIs) were determined by using Clopper–Pears on exact method on the basis of observed case data. Subgroup analyses were performed by age ( 7) on PSA0.2. Adverse drug reactions (ADRs) were collected for safety evaluation. Results: There were 300 pts with mHSPC treated with APA plus ADT analyzed. Median treatment duration was 12.8 (range 0.1–13.5) mo. Baseline characteristics were as follows: median age 72 (range 40–97) yr, Gleason score > 7 in 84% (172/204) of pts, tumor stage T3 in 22/84 and T4 in 51/84 pts, median PSA100 (range 0.1–5000) ng/mL. PSA0.2 response was 41.1% at M3, increasing to 62% at M6 and 69.7% at M12. PSA50 and PSA90 responses were 98.8% and 92% at M3, respectively. PSA progression (increase ≥50% and ≥5 ng/mL above nadir) occurred in 7 pts; clinical and radiographic disease progression occurred in 2 pts and 1 pt. Regarding safety analysis, ADRs were reported in 13% of pts, with ADRs (grade 3–4) reported in 1%. 4 deaths were reported. PSA0.2 response did not show meaningful difference across subgroups. Conclusions: The CAPABLE, the largest published APA real-world study in China, reveals a notably high PSA response for APA plus ADT, with infrequent progression reported, indicating a favorable prognosis for pts with mHSPC. The regimen also has a tolerable safety profile. PSA response among pts with mHSPC after APA plus ADT treatment. % (n/N) 95% CI PSA0.2M3M6M12 41.1% (76/185)62% (98/158)69.7% (99/142) 33.9%–48.5%54%–69.6%61.5%–77.1% PSA50M3M6M12 98.8% (160/162)97.1% (134/138)95.3% (121/127) 95.6%–99.9%92.7%–99.2%90%–98.2% PSA90M3M6M12 92% (149/162)91.3% (126/138)92.9% (118/127) 86.7%–95.7%85.3%–95.4%87%–96.7%
Wang et al. (Thu,) studied this question.