Abstract 594P
Background
Ra-223 is a bone targeted alpha emitter approved for treatment of mCRPC on the basis of a significant survival advantage and favorable safety profile vs placebo in a phase III trial. Ra-223 also delayed opioid use and external beam radiotherapy vs placebo in post hoc analyses of that trial. PARABO (NCT02398526) is a prospective, observational, noninterventional, single-arm study evaluating pain efficacy in pts with mCRPC treated with Ra-223 in German real-life nuclear medicine settings.
Methods
The primary outcome was pain response, defined as a ≥2 point improvement in Brief Pain Inventory short form (BPI-SF) worst pain score in pts with baseline worst pain >1. Here we assessed pain response in the overall population and by extent of disease (EOD; ≤20 vs >20 lesions), opioid use, and Ra-223 cycles received (5–6 vs ≤4). BPI-SF component scores were assessed at each visit.
Results
This analysis (data cutoff July 16, 2020) includes 354 pts who started Ra-223 between Mar 2015 and Dec 2017. At baseline, 260 pts (73%) had Eastern Cooperative Oncology Group performance status 0/1; 37 (10%) had <6 metastatic lesions, 124 (35%) had 6–20 lesions, 127 (36%) had >20 lesions, and 55 (15%) had a superscan; 242 pts (68%) had received prior systemic life-prolonging therapy (median 2). In total, 169 pts (48%) used opioids at any time (116 used opioids before/at baseline, 53 started opioids during Ra-223 therapy). Overall, pts received a median of 6 Ra-223 injections (range 1–6); 236 (67%) had 5–6 injections, and 118 (33%) had ≤4 injections. Of 216 pts with baseline worst pain >1, 128 (59%) had a clinically meaningful pain response; the rate was 60% in pts with ≤20 lesions vs 59% in pts with >20 lesions; 65% in pts with opioid use vs 54% in pts without opioid use; and 67% in pts with 5–6 Ra-223 injections vs 43% in pts with ≤4 injections. Mean BPI-SF component scores during Ra-223 treatment improved or were maintained from baseline, regardless of EOD or opioid use.
Conclusions
In this real-life study, pts with mCRPC experienced reduction of bone-associated pain during Ra-223 therapy, regardless of EOD or opioid use. The benefit appeared most pronounced in pts who received 5–6 cycles of Ra-223.
Clinical trial identification
NCT02398526.
Editorial acknowledgement
Sara Black, ISMPP CMPP™, from OPEN Health, London, UK, provided medical writing support.
Legal entity responsible for the study
Bayer AG, Berlin, Germany.
Funding
Bayer AG, Berlin, Germany.
Disclosure
K. Liepe: Financial Interests, Personal, Other, Consultant: Serene; Financial Interests, Personal, Other, Consultant: Rotop. F.M. Mottaghy: Financial Interests, Personal, Advisory Board: Novartis; Financial Interests, Personal, Advisory Board: NanoMab; Financial Interests, Institutional, Research Grant: GE; Financial Interests, Institutional, Research Grant: Siemens; Financial Interests, Institutional, Research Grant: NonoMab. R. Guan: Financial Interests, Personal, Full or part-time Employment: Bayer. J. Pinkert: Financial Interests, Personal, Full or part-time Employment: Bayer. S. Buetikofer: Financial Interests, Personal, Full or part-time Employment: Bayer. K. Herrmann: Financial Interests, Personal, Other, Personal fees: Bayer; Financial Interests, Personal, Other, personal fees: Sofie Biosciences; Financial Interests, Personal, Other, personal fees: Sirtex; Financial Interests, Personal, Other, personal fees: Adacap; Financial Interests, Personal, Other, Personal fees: Curium; Financial Interests, Personal, Other, personal fees: Endocyte; Financial Interests, Personal, Other, personal fees: BTG; Financial Interests, Personal, Other, personal fees: Ipsen; Financial Interests, Personal, Other, personal fees: Siemens Healthineers; Financial Interests, Personal, Other, personal fees: GE Healthcare; Financial Interests, Personal, Other, personal fees: Amgen; Financial Interests, Personal, Other, personal fees: Novartis; Financial Interests, Personal, Other, personal fees: Y-mAbs; Financial Interests, Personal, Other, personal fees: Aktis Oncology; Financial Interests, Personal, Other, personal fees: Theragnostics; Financial Interests, Personal, Other, personal fees: Pharma 15; Non-Financial Interests, Personal, Other, non financial support: ABX. All other authors have declared no conflicts of interest.