Abstract 1918P
Background
MKIs effectively prolong progression-free survival in patients with RAI-R DTC, but are associated with notable toxicity. There is currently no consensus on when patients with asymptomatic RAI-R DTC should initiate systemic treatment.
Methods
RIFTOS MKI is a global non-interventional study, enrolling patients with asymptomatic RAI-R DTC, designed to evaluate outcomes of patients treated with/without MKIs at study entry. Here we report baseline characteristics and safety from the final analysis; effectiveness results are pending.
Results
Of the 656 patients enrolled and valid for analysis, 45% were male, median age was 67 years, and median weight was 75 kg; median duration of observation was 27.7 months. At study entry most patients had an Eastern Cooperative Oncology Group performance status of 0 or 1 (95%), the most frequent histology was papillary (74%), and 91% of patients had metastatic disease. The median time from initial DTC diagnosis to study entry was 6.7 years, and RAI refractoriness was mainly due to lack of RAI uptake (64%). The median average dose and median cumulative dose of prior RAI treatment were 127.8 mCi (4.73 GBq) and 250.0 mCi (9.25 GBq), respectively. Overall, 205 patients (31%) received sorafenib, and 217 patients (33%) received another MKI at any time during the study, including lenvatinib (30%). Median duration of sorafenib exposure was 13.1 months, and most patients received an initial dose of 800 mg/day. Of the 205 patients included in the sorafenib safety analysis, 181 (88%) had ≥1 adverse event (AE) and 68 (33%) had ≥1 serious AE; 86 patients (42%) reported hand–foot skin reaction (HFSR), and 18 patients (9%) grade ≥3 HFSR.
Conclusions
The final analysis of RIFTOS MKI provides baseline characteristics and treatment practices for patients with asymptomatic RAI-R DTC under real-life conditions. Safety data from patients treated with sorafenib are consistent with sorafenib’s known safety profile. Of note, HFSR seems to be reported less frequently in real-life practice than in phase III clinical trials.
Clinical trial identification
NCT02303444.
Editorial acknowledgement
Editorial assistance in the writing of this abstract was provided by Victoria Jones of OPEN Health Medical Communications (Choice), with financial support from Bayer.
Legal entity responsible for the study
Bayer.
Funding
Bayer.
Disclosure
M.S. Brose: Honoraria (self), Advisory/Consultancy, Research grant/Funding (institution): Bayer. C-C. Lin: Advisory/Consultancy: Bayer; Travel/Accommodation/Expenses: BeiGene; Advisory/Consultancy: Blueprint Medicines; Advisory/Consultancy: Bristol-Myers Squibb; Honoraria (self), Advisory/Consultancy: Daiichi-Sankyo; Advisory/Consultancy: Eisai; Travel/Accommodation/Expenses: Eli Lilly; Honoraria (self), Advisory/Consultancy: Novartis; Honoraria (self): Roche. M. Tori: Research grant/Funding (institution): Bayer; Research grant/Funding (institution): Eisai. F. Worden: Honoraria (self), Travel/Accommodation/Expenses: Merck Sharp & Dohme; Honoraria (self), Advisory/Consultancy, Research grant/Funding (institution): Eisai; Honoraria (self), Research grant/Funding (institution): Bristol-Myers Squibb; Honoraria (self), Advisory/Consultancy, Research grant/Funding (institution): LOXO; Honoraria (self), Advisory/Consultancy, Travel/Accommodation/Expenses: Bayer; Honoraria (self), Advisory/Consultancy: Cue Biopharma; Advisory/Consultancy: Rakuten; Advisory/Consultancy, Research grant/Funding (institution): Merck; Research grant/Funding (institution): Oragenics; Research grant/Funding (institution): Eli Lilly; Research grant/Funding (institution): Pfizer. D.H-Y. Shen: Honoraria (self), Advisory/Consultancy: Bayer Taiwan; Honoraria (self), Advisory/Consultancy: Eisai Taiwan; Honoraria (self): Roche Diagnostics Taiwan; Advisory/Consultancy: Roche Taiwan. R.P. Peeters: Honoraria (self): Bayer; Honoraria (self): Ibsa; Honoraria (self): Merck. S. Takahashi: Speaker Bureau/Expert testimony, Research grant/Funding (institution): Bayer; Speaker Bureau/Expert testimony, Research grant/Funding (institution): Eisai. P. Rumyantsev: Speaker Bureau/Expert testimony: Bayer; Advisory/Consultancy, Speaker Bureau/Expert testimony: Eisai. R. Guan, S. Babajanyan, K. Ozgurdal: Full/Part-time employment: Bayer. I. Sugitani: Research grant/Funding (institution): Bayer. F. Pitoia: Speaker Bureau/Expert testimony: Bayer; Speaker Bureau/Expert testimony: Eisai. L. Lamartina: Honoraria (self): Eisai; Advisory/Consultancy: Bayer. All other authors have declared no conflicts of interest.