A registry-based study evaluating overall survival and treatment duration in Swedish patients with metastatic castration-resistant prostate cancer treated with enzalutamide

Figures & data

Table 1. Key differences in patient characteristics at baseline in the registry study conducted at Skåne University Hospital and randomised clinical trials of enzalutamide in patients with mCRPC [5,6,14,15].

	Pre-chemotherapy		Post-chemotherapy
	Patient registry (n = 102)	PREVAIL* (n = 872)	Patient registry (n = 98)	AFFIRM* (n = 800)
Age, years
Median	77	72	72	69
Range	56–95	43–93	46–84	41–92
Interquartile range	72–82	NR	67–75	NR
≥75, %	59	36.3	24	24.9
ECOG performance status  at baseline^a
Patients, n	94	872	94	800
Score, %
0	55	67	48	91.3 (0 or 1)
1	23	33	35	91.3 (0 or 1)
≥2	15	0	13	8.8
Total Gleason score^b
Patients, n	93	838	94	800
Score
≤7, % (< 7, for registry)	18	49.4	6	49.6
≥8, % (≥7, for registry)	73	50.6	90	50.4
Median	8	NR	8	8
Plasma PSA at baseline
Patients, n	97	872	94	800
Median, ng/mL	53	54.1	91.5	107.7
Range, ng/mL	2.4–4822	0.1–3182	0.5–5000	0.2–11794
Time from diagnosis of  prostate cancer
Patients, n	102	872	98	800
Median, months	9.0	62.7	19.7	70.8
Treatment-stopping criteria^c	At discretion of treating physician; could include clinical progression, new symptoms or impaired general condition	Confirmed radiographic progression and initiation of new systemic antineoplastic therapy required	At discretion of treating physician; could include clinical progression, new symptoms or impaired general condition	Confirmed radiographic progression and initiation of new systemic antineoplastic therapy required
Select exclusion criteria	Comorbid conditions not addressed in exclusion criteria; all patients treated with enzalutamide included	Severe concurrent disease, infection, comorbid condition, known/suspected brain metastases, clinically significant CVD	Comorbid conditions not addressed in exclusion criteria; all patients treated with enzalutamide included	Severe concurrent disease, infection, comorbid condition, known/suspected brain metastases, clinically significant CVD

^* Active treatment group only.

^a ECOG performance scores were reported separately as 0 and 1 in the registry study and PREVAIL; in AFFIRM, scores 0–1 were grouped together.

^b Gleason scores were reported as < 7 or ≥7 in the registry study, and as ≤7 or ≥8 in AFFIRM and PREVAIL.

^c Aggregated data on treatment discontinuation is described in Supplementary Tables S2–S4.

CVD: cardiovascular disease; ECOG: Eastern Cooperative Oncology Group; mCRPC: metastatic castration-resistant prostate cancer; NR: not reported; PSA: prostate-specific antigen.

Figure 1. Kaplan–Meier plot of overall median survival from enzalutamide initiation to death from any cause in post-chemotherapy patients with mCRPC and prior docetaxel treatment. HR: hazard ratio; mCRPC: metastatic castration-resistant prostate cancer. ^aHR from time-to-event analysis.

Figure 2. Kaplan–Meier plot of median treatment duration, from enzalutamide initiation to all-cause treatment discontinuation in pre-chemotherapy patients with mCRPC. HR: hazard ratio; mCRPC: metastatic castration-resistant prostate cancer. ^aHR from time-to-event analysis.

Figure 3. Kaplan–Meier plot of median treatment duration, from enzalutamide initiation to all-cause treatment discontinuation in post-chemotherapy patients with mCRPC. HR: hazard ratio; mCRPC: metastatic castration-resistant prostate cancer. ^aHR from time-to-event analysis.

Table 2. Efficacy outcomes in the Skåne registry study and randomised clinical trials of enzalutamide in patients with mCRPC treated pre- and post-chemotherapy [5,6].

	Pre-chemotherapy		Post-chemotherapy
	Patient registry (n = 102)	PREVAIL* (n = 872)	Patient registry (n = 98)	AFFIRM* (n = 800)
Overall survival, months
Median	NA	32.4	14.3	18.4
95% CI	NA	30.1–NYR	11.0–18.2	17.3–NYR
Patients alive at time of analysis, %	NR	72	20	62
Duration of treatment, months
Median	13.8	16.6	7.6	8.3
95% CI	11.4–20.2	NR	6.3–10.2	NR
Patients on treatment at time of analysis, %	45	42	12	29

^* Active treatment group only.

CI: confidence interval; mCRPC: metastatic castration-resistant prostate cancer; NA: not applicable; NR: not reported; NYR: not yet reached.

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Beer TM, Armstrong AJ, Rathkopf DE, et al. Enzalutamide in metastatic prostate cancer before chemotherapy. N Engl J Med. 2014;371:424–433.

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ClinicalTrials.gov [Internet]. A safety and efficacy study of oral MDV3100 in chemotherapy-naive patients with progressive metastatic prostate cancer (PREVAIL); [cited 2019 Jul 10]. Available from: https://clinicaltrials.gov/ct2/show/NCT01212991.

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ClinicalTrials.gov [Internet]. Safety and efficacy study of MDV3100 in patients with castration-resistant prostate cancer who have been previously treated with docetaxel-based chemotherapy (AFFIRM); [cited 2019 Jul 10]. Available from: https://clinicaltrials.gov/ct2/show/NCT01212991.

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Data availability

Access to anonymised individual participant-level data will not be provided for this trial, as it meets one or more of the exceptions described on www.clinicalstudydatarequest.com under ‘Sponsor Specific Details for Astellas’. The ethical approval limits the access to data.