Dag Clement Johannessen

Alpha Emitter Radium-223 and Survival in Metastatic Prostate Cancer

BACKGROUND Radium-223 dichloride (radium-223), an alpha emitter, selectively targets bone metastases with alpha particles. We assessed the efficacy and safety of radium-223 as compared with placebo, in addition to the best standard of care, in men with castration-resistant prostate cancer and bone metastases. METHODS In our phase 3, randomized, double-blind, placebo-controlled study, we randomly assigned 921 patients who had received, were not eligible to receive, or declined docetaxel, in a 2:1 ratio, to receive six injections of radium-223 (at a dose of 50 kBq per kilogram of body weight intravenously) or matching placebo; one injection was administered every 4 weeks. In addition, all patients received the best standard of care. The primary end point was overall survival. The main secondary efficacy end points included time to the first symptomatic skeletal event and various biochemical end points. A prespecified interim analysis, conducted when 314 deaths had occurred, assessed the effect of radium-223 versus placebo on survival. An updated analysis, when 528 deaths had occurred, was performed before crossover from placebo to radium-223. RESULTS At the interim analysis, which involved 809 patients, radium-223, as compared with placebo, significantly improved overall survival (median, 14.0 months vs. 11.2 months; hazard ratio, 0.70; 95% confidence interval [CI], 0.55 to 0.88; two-sided P=0.002). The updated analysis involving 921 patients confirmed the radium-223 survival benefit (median, 14.9 months vs. 11.3 months; hazard ratio, 0.70; 95% CI, 0.58 to 0.83; P<0.001). Assessments of all main secondary efficacy end points also showed a benefit of radium-233 as compared with placebo. Radium-223 was associated with low myelosuppression rates and fewer adverse events. CONCLUSIONS In this study, which was terminated for efficacy at the prespecified interim analysis, radium-223 improved overall survival. (Funded by Algeta and Bayer HealthCare Pharmaceuticals; ALSYMPCA ClinicalTrials.gov number, NCT00699751.).

Bone-targeted radium-223 in symptomatic, hormone-refractory prostate cancer: a randomised, multicentre, placebo-controlled phase II study

BACKGROUND The alpha-emitter radium-223 ((223)Ra) is a bone-seeking radionuclide studied as a new treatment for patients with bone metastases from hormone-refractory prostate cancer. We aimed to study mature outcomes from a randomised, multicentre, phase II study of (223)Ra. METHODS Patients with hormone-refractory prostate cancer and bone pain needing external-beam radiotherapy were assigned to four intravenous injections of (223)Ra (50 kBq/kg, 33 patients) or placebo (31 patients), given every 4 weeks. Primary endpoints were change in bone-alkaline phosphatase (ALP) concentration and time to skeletal-related events (SREs). Secondary endpoints included toxic effects, time to prostate-specific-antigen (PSA) progression, and overall survival. All tests were done at a 5% significance level, based on intention to treat. FINDINGS Median relative change in bone-ALP during treatment was -65.6% (95% CI -69.5 to -57.7) and 9.3% (3.8-60.9) in the (223)Ra group and placebo groups, respectively (p<0.0001, Wilcoxon ranked-sums test). Hazard ratio for time to first SRE, adjusted for baseline covariates, was 1.75 (0.96-3.19, p=0.065, Cox regression). Haematological toxic effects did not differ significantly between two groups. No patient discontinued (223)Ra because of treatment toxicity. Median time to PSA progression was 26 weeks (16-39) versus 8 weeks (4-12; p=0.048) for (223)Ra versus placebo, respectively. Median overall survival was 65.3 weeks (48.7-infinity) for (223)Ra and 46.4 weeks (32.1-77.4) for placebo (p=0.066, log rank). The hazard ratio for overall survival, adjusted for baseline covariates was 2.12 (1.13-3.98, p=0.020, Cox regression). INTERPRETATION (223)Ra was well tolerated with minimum myelotoxicity, and had a significant effect on bone-ALP concentrations. Larger clinical trials are warranted to study (223)Ra on the prevention of SREs and on overall survival in patients with hormone-refractory prostate cancer. Bone-targeting properties of (223)Ra could also potentially be used for treating skeletal metastasis from other primary cancers.

Effect of radium-223 dichloride on symptomatic skeletal events in patients with castration-resistant prostate cancer and bone metastases: results from a phase 3, double-blind, randomised trial

BACKGROUND Bone metastases frequently cause skeletal events in patients with metastatic castration-resistant prostate cancer. Radium-223 dichloride (radium-223) selectively targets bone metastases with high-energy, short-range α-particles. We assessed the effect of radium-223 compared with placebo in patients with castration-resistant prostate cancer and bone metastases. METHODS In this phase 3, double-blind, randomised ALSYMPCA trial, we enrolled patients who had symptomatic castration-resistant prostate cancer with two or more bone metastases and no known visceral metastases, who were receiving best standard of care, and had previously either received or were unsuitable for docetaxel. Patients were stratified by previous docetaxel use, baseline total alkaline phosphatase level, and current bisphosphonate use, then randomly assigned (2:1) to receive either six intravenous injections of radium-223 (50 kBq/kg) or matching placebo; one injection was given every 4 weeks. Randomisation was done with an interactive voice response system, taking into account trial stratification factors. Participants and investigators were masked to treatment assignment. The primary endpoint was overall survival, which has been reported previously. Here we report on time to first symptomatic skeletal event, defined as the use of external beam radiation to relieve bone pain, or occurrence of a new symptomatic pathological fracture (vertebral or non-verterbal), or occurence of spinal cord compression, or tumour-related orthopeadic surgical intervention. All events were required to be clinically apparent and were not assessed by periodic radiological review. Statistical analyses of symptomatic skeletal events were based on the intention-to-treat population. The study has been completed and is registered with ClinicalTrials.gov, number NCT00699751. FINDINGS Between June 12, 2008, and Feb 1, 2011, 921 patients were enrolled, of whom 614 (67%) were randomly assigned to receive radium-223 and 307 (33%) placebo. Symptomatic skeletal events occurred in 202 (33%) of 614 patients in the radium-223 group and 116 (38%) of 307 patients in the placebo group. Time to first symptomatic skeletal event was longer with radium-223 than with placebo (median 15·6 months [95% CI 13·5-18·0] vs 9·8 months [7·3-23·7]; hazard ratio [HR]=0·66, 95% CI 0·52-0·83; p=0·00037). The risks of external beam radiation therapy for bone pain (HR 0·67, 95% CI 0·53-0·85) and spinal cord compression (HR=0·52, 95% CI 0·29-0·93) were reduced with radium-233 compared with placebo. Radium-223 treatment did not seem to significantly reduce the risk of symptomatic pathological bone fracture (HR 0·62, 95% CI 0·35-1·09), or the need for tumour-related orthopaedic surgical intervention (HR 0·72, 95% CI 0·28-1·82). INTERPRETATION Radium-223 should be considered as a treatment option for patients with castration-resistant prostate cancer and symptomatic bone metastases. FUNDING Algeta and Bayer HealthCare Pharmaceuticals.

Efficacy and safety of radium-223 dichloride in patients with castration-resistant prostate cancer and symptomatic bone metastases, with or without previous docetaxel use: a prespecified subgroup analysis from the randomised, double-blind, phase 3 ALSYMPCA trial

BACKGROUND Primary results from the phase 3 ALSYMPCA trial showed that radium-223 dichloride (radium-223), a targeted α-emitter, improved overall survival compared with placebo and was well tolerated in patients with castration-resistant prostate cancer and symptomatic bone metastases. We did a prespecified subgroup analysis from ALSYMPCA to assess the effect of previous docetaxel use on the efficacy and safety of radium-223. METHODS In the phase 3, randomised, double-blind ALSYMPCA trial, patients with symptomatic castration-resistant prostate cancer, at least two symptomatic bone metastases, no known visceral metastases, and who were receiving best standard of care were randomly assigned (2:1) via an interactive voice response system to receive six injections of radium-223 (50 kBq/kg intravenously) or matching placebo, with one injection given every 4 weeks. Patients had either received previous docetaxel treatment or were unsuitable for or declined docetaxel; previous docetaxel use (yes or no) was a trial stratification factor. We investigated the effect of previous docetaxel use on radium-223 treatment for the primary endpoint of overall survival, the main secondary efficacy endpoints, and safety. Efficacy analyses were done for the intention-to-treat population; safety analyses were done for the safety population. The trial has been completed and is registered with ClinicalTrials.gov, number NCT00699751. FINDINGS Randomisation took place between June 12, 2008, and Feb 1, 2011. 526 (57%) of 921 randomly assigned patients had received previous docetaxel treatment (352 in the radium-223 group and 174 in the placebo group) and 395 (43%) had not (262 in the radium-223 group and 133 in the placebo group). Radium-223 prolonged median overall survival compared with placebo, irrespective of previous docetaxel use (previous docetaxel use, hazard ratio [HR] 0·70, 95% CI 0·56-0·88; p=0·002; no previous docetaxel use, HR 0·69, 0·52-0·92; p=0·01). The benefit of radium-223 compared with placebo was seen in both docetaxel subgroups for most main secondary efficacy endpoints; risk for time to time to first symptomatic skeletal event was reduced with radium-223 versus placebo in patients with previous docetaxel use, but the difference was not significant in those with no previous docetaxel use. 322 (62%) of 518 patients previously treated with docetaxel had grade 3-4 adverse events, compared with 205 (54%) of 383 patients without docetaxel. Patients who had previously been treated with docetaxel had a higher incidence of grade 3-4 thrombocytopenia with radium-223 than with placebo (31 [9%] of 347 patients vs five [3%] of 171 patients), whereas the incidence was similar between treatment groups among patients with no previous docetaxel use (seven [3%] of 253 patients vs one [1%] of 130 patients). The incidences of grade 3-4 anaemia and neutropenia were similar between the radium-223 and placebo groups within both docetaxel subgroups. INTERPRETATION Radium-223 is effective and well tolerated in patients with castration-resistant prostate cancer and symptomatic bone metastases, irrespective of previous docetaxel use. FUNDING Algeta ASA and Bayer HealthCare Pharmaceuticals.

Overall survival benefit and safety profile of radium-223 chloride, a first-in-class alpha-pharmaceutical: Results from a phase III randomized trial (ALSYMPCA) in patients with castration-resistant prostate cancer (CRPC) with bone metastases.

8 Background: Radium-223 chloride (Ra-223) is a first-in-class alpha-pharmaceutical targeting bone metastases (mets) with high-energy alpha-particles of extremely short range (<100 μm). ALSYMPCA, a phase III, double-blind, randomized, multinational study, compared efficacy, in terms of overall survival (OS), and safety of Ra-223 plus best standard of care (BSC) vs placebo plus BSC in patients (pts) with bone mets in CRPC. METHODS Eligible pts had progressive, symptomatic CRPC with ≥ 2 bone mets on scintigraphy and no known visceral mets; were receiving BSC; and either previously received docetaxel, were docetaxel ineligible, or refused docetaxel. Pts were randomized 2:1 to receive 6 injections of Ra-223 (50 kBq/kg IV) q4 wks or matching placebo and stratified by prior docetaxel use, baseline alkaline phosphatase level, and current bisphosphonate use. A planned interim analysis (IA) was conducted to assess the effect of Ra-223 on the primary endpoint (OS) using a predefined threshold. Survival data were compared using a stratified log-rank test. RESULTS 922 pts (Ra-223, n = 615; placebo, n = 307) were randomized from 6/2008-2/2011. 445 (58%) of 809 pts in the IA data set received prior treatment with docetaxel. Ra-223 significantly improved OS in pts with CRPC with bone mets vs placebo (two-sided P = 0.00185; HR = 0.695; 95% CI, 0.552-0.875; median OS 14.0 mo vs 11.2 mo, respectively). Safety and tolerability of Ra-223 were highly favorable and showed low incidence of myelosuppression (eg, grades 3/4 neutropenia in 1.8% and 0.8% and thrombocytopenia in 4% and 2% of the Ra-223 and placebo groups, respectively). CONCLUSIONS Ra-223 is an effective therapy that improved OS with a highly favorable safety profile, and may provide a new standard of care for the treatment of CRPC pts with bone mets. [Table: see text].

Two-Year Survival Follow-Up of the Randomized, Double-Blind, Placebo-Controlled Phase II Study of Radium-223 Chloride in Patients With Castration-Resistant Prostate Cancer and Bone Metastases

BACKGROUND This phase II randomized, placebo-controlled study was conducted to evaluate efficacy and safety of radium-223 in patients with castration-resistant prostate cancer (CRPC) and painful bone metastases. Twelve- and 18-month survival results were reported previously. Here we report 24-month overall survival (OS) and safety data from the period 12 to 24 months after the first injection of study medication. METHODS Patients with CRPC and bone pain were randomized 1:1 to receive 4 injections of radium-223 (50 kBq/kg [n = 33]) or placebo (n = 31) after external-beam radiotherapy; each injection was given every 4 weeks. Endpoints for this report were 24-month OS, long-term safety, and treatment-related adverse events (AEs) occurring in the 12- to 24-month period. RESULTS After 24 months, 10 (30%) patients were alive in the radium-223 group compared with 4 patients (13%) in the placebo group. Patients who received at least 1 dose of study medication had a median OS of 65 weeks in the radium-223 group vs. 46 weeks in the placebo group (log-rank P = .056). The hazard ratio (HR) for OS, adjusted for baseline covariates, was 0.476 (95% confidence interval [CI], 0.258-0.877; Cox regression P = .017). The most frequent cause of death for both arms was disease progression. There were no reports of treatment-related AEs or long-term hematologic toxicity during the 12- to 24-month follow-up. CONCLUSION Radium-223 had a highly favorable safety profile, with no evidence of second malignancies at 24-month follow-up. The significant improvement in OS observed in patients receiving radium-223 vs. placebo suggests that treatment of bone disease with radium-223 has survival benefits.

Updated analysis of the phase III, double-blind, randomized, multinational study of radium-223 chloride in castration-resistant prostate cancer (CRPC) patients with bone metastases (ALSYMPCA)

LBA4512 Background: Radium-223 chloride (Ra-223), a targeted alpha-emitter, targets bone metastases (mets) with high-energy alpha-particles of short range (<100 µm). ALSYMPCA, a phase III double-blind, randomized, multinational study, compared Ra-223 plus best standard of care (BSC) vs placebo plus BSC in CRPC patients (pts) with bone mets. In a planned interim analysis (n = 809), based on 314 events, Ra-223 significantly improved overall survival (OS) vs placebo (median 14.0 mo vs 11.2 mo, respectively; HR = .695; 95% CI, .552-.875; 2-sided p = .00185). Secondary endpoints were met and Ra-223 safety was favorable. An updated analysis was conducted prior to the crossover to further assess the effect of Ra-223 on the primary endpoint (OS), secondary endpoints including skeletal-related events (SREs), and safety. METHODS Eligible pts had confirmed symptomatic CRPC with ≥ 2 bone mets; no known visceral mets; and were post-docetaxel, unfit for docetaxel, or had declined docetaxel. Pts were randomized 2:1 to receive 6 injections of Ra-223 (50 kBq/kg IV) q4wks or matching placebo. An updated descriptive analysis of OS, based on 528 events, was performed including data from all randomized pts prior to implementing crossover to Ra-223 for placebo pts. RESULTS 921 pts (Ra-223, n = 614; placebo, n = 307) were randomized from 6/2008-2/2011. Ra‑223 significantly improved OS vs placebo (median 14.9 mo vs 11.3 mo, respectively; HR = .695; 95% CI, .581-.832; p = 0.00007), and time to first SRE was significantly prolonged (median 15.6 mo vs 9.8 mo, respectively; HR = 0.658; 95% CI, 0.522-0.830; p = 0.00037). Safety and tolerability of Ra-223 remained favorable, with low myelosuppression (e.g., gr 3/4 neutropenia in 2.2% and 0.7% and gr 3/4 thrombocytopenia in 6.3% and 2% of the Ra-223 and placebo groups, respectively). CONCLUSIONS On updated analysis, the median OS benefit for Ra-223 increased from 2.8 to 3.6 months, with a hazard ratio of 0.695 (i.e., 30.5% reduction in risk of death). Ra-223 is an effective therapy that improves OS and time to first SRE with a highly favorable safety profile, and may provide a new standard of care for CRPC pts with bone mets.

Relations between sex hormones, sex hormone binding globulin, insulin-like growth factor-I and insulin-like growth factor binding protein-1 in post-menopausal breast cancer patients.

OBJECTIVE Oestrogens, androgens and anti‐endocrine drugs such as tamoxifen and aminoglutethimide influence plasma Insulin‐like growth factor‐I (IGF‐I). IGF‐I, in turn, has been found to stimulate the peripheral aromatase in vitro. The aim of this study was to examine relations between sex hormones, IGF‐I and insulin‐like growth factor binding protein‐1 (IGFBP‐1) In post‐menopausal women with breast cancer.

Influence of tamoxifen on sex hormones, gonadotrophins and sex hormone binding globulin in postmenopausal breast cancer patients.

Estrone sulphate (E1S) may be an important estrogen source in breast cancers, particularly in postmenopausal women. Recent studies have shown that tamoxifen inhibits the uptake and metabolism of E1S to estradiol (E2) in cell cultures. To evaluate a possible influence of tamoxifen on E1S disposition in vivo, we measured plasma levels of E1S together with unconjugated estrogens (E1 and E2), androgens (T, A, DHEA and DHEAS), SHBG, FSH and LH in 32 postmenopausal breast cancer patients before and during tamoxifen treatment. In a subgroup of 10 patients, we measured 24 h urinary excretion of estrogen metabolites to evaluate the influence of tamoxifen treatment on estrogen metabolism and total estrogen production. Tamoxifen increased plasma levels of E1S (mean increase of 18.1%, P < 0.05) and the ratio of E1S/E1 (mean increase of 25.7%, P < 0.01) and E1S/E2 (mean increase of 34.7%, P < 0.0005). No significant change in plasma E1 was seen, but plasma E2 was reduced (mean reduction of 12.1%, P < 0.005). The fall in plasma E2 was probably secondary to a fall in plasma T (mean reduction of 11.9%, P < 0.05) due to a reduced ovarian excretion of this androgen. The mechanisms may be a reduced gonadotrophin stimulation of the ovary, as plasma FSH and LH fell by mean values of 45.5 and 48.1%, respectively (P < 0.0001 for both). The increase in plasma E1S was accompanied by a reduced ratio of 2OHE1/E1 in urine (mean reduction of 38.2%, P < 0.025) indicating reduced 2-hydroxylation. Possible mechanisms for these alterations are discussed.

INTENSITY-MODULATED RADIOTHERAPY OF PELVIC LYMPH NODES IN LOCALLY ADVANCED PROSTATE CANCER: PLANNING PROCEDURES AND EARLY EXPERIENCES

PURPOSE We present planning and early clinical outcomes of a study of intensity-modulated radiotherapy (IMRT) for locally advanced prostate cancer. METHODS AND MATERIALS A total of 43 patients initially treated with an IMRT plan delivering 50 Gy to the prostate, seminal vesicles, and pelvic lymph nodes, followed by a conformal radiotherapy (CRT) plan delivering 20 Gy to the prostate and seminal vesicles, were studied. Dose-volume histogram (DVH) data for the added plans were compared with dose-volume histogram data for the sum of two CRT plans for 15 cases. Gastrointestinal (GI) and genitourinary (GU) toxicity, based on the Radiation Therapy Oncology Group scoring system, was recorded weekly throughout treatment as well as 3 to 18 months after treatment and are presented. RESULTS Treatment with IMRT both reduced normal tissue doses and increased the minimum target doses. Intestine volumes receiving more than 40 and 50 Gy were significantly reduced (e.g., at 50 Gy, from 81 to 19 cm(3); p = 0.026), as were bladder volumes above 40, 50, and 60 Gy, rectum volumes above 30, 50, and 60 Gy, and hip joint muscle volumes above 20, 30, and 40 Gy. During treatment, Grade 2 GI toxicity was reported by 12 of 43 patients (28%), and Grade 2 to 4 GU toxicity was also observed among 12 patients (28%). With 6 to 18 months of follow-up, 2 patients (5%) experienced Grade 2 GI effects and 7 patients (16%) experienced Grade 2 GU effects. CONCLUSIONS Use of IMRT for pelvic irradiation in prostate cancer reduces normal tissue doses, improves target coverage, and has a promising toxicity profile.