Publication
Disease Characteristics and Completion of Treatment in Patients With Metastatic Castration-Resistant Prostate Cancer Treated With Radium-223 in an International Early Access Program
Journal Paper/Review - May 31, 2019
Saad Fred, Carles Joan, Seger Monica, Reeves John, Wirth Manfred, Miller Kurt, Nilsson Sten, O'Sullivan Joe M, Keizman Daniel, Heinrich Daniel, Gillessen Sommer Silke, Heidenreich Axel
Units
PubMed
Doi
Citation
Type
Journal
Publication Date
Issn Electronic
Pages
Brief description/objective
BACKGROUND
Radium-223 is approved by the US Food and Drug Administration and European Medicines Agency for the treatment of metastatic castration-resistant prostate cancer (mCRPC). There are currently no markers for selecting patients most likely to complete radium-223 treatment.
PATIENTS AND METHODS
In this phase IIIb, international, single-arm study, patients received radium-223, 55 kBq/kg, every 4 weeks for ≤6 cycles. Primary end points were safety and overall survival. In post hoc analyses patients were grouped according to number of radium-223 injections received (1-4 or 5-6). Associations between baseline covariates and number of injections were investigated.
RESULTS
Of 696 eligible patients, 473 (68%) had received 5 to 6 radium-223 injections and 223 (32%) 1 to 4 injections. Patients with less pain (moderate-severe vs. none-mild, odds ratio [OR], 0.41; P < .0001), lower Eastern Cooperative Oncology Group performance status (≥2 vs. 0-1, OR, 0.51; P = .0074), lower prostate-specific antigen level (>141 μg/L vs. ≤141 μg/L, OR, 0.40; P < .0001), and higher hemoglobin level (<10 g/dL vs. ≥10 g/dL, OR, 0.50; P = .0206) were more likely to receive 5 to 6 than 1 to 4 injections. Median overall survival was not reached and was 6.3 months (95% confidence interval, 5.4-7.4) in patients who had received 5 to 6 and 1 to 4 radium-223 injections, respectively. Adverse events were less common in patients who received 5 to 6 than 1 to 4 injections; anemia was reported in 87 (18%) and 64 (29%) patients, respectively.
CONCLUSION
Patients with less advanced mCRPC are more likely to receive 5 to 6 radium-223 injections and to achieve better overall survival. Consideration of baseline and disease characteristics is recommended before initiation of radium-223 treatment.