4CPS-295 Immunotherapy for cancer therapeutic positioning reports: knowledge, expectations and experiences through a national survey

Abstract

Background and importance Regorafenib (REG) and trifluridine-tipiracil (TAS-102) are used in metastatic colorectal cancer (mCRC) after failure of conventional therapy based on fluorouracil (5-FU) schemes. Aim and objectives To evaluate the efficacy and safety of TAS-102 and regorafenib drugs in patients with mCRC. Material and methods A retrospective single centre study was conducted from January 2010 to August 2020, which included all patients diagnosed with CRBM treated with TAS-102/REG. Clinical and demographic variables were collected, corresponding to age, sex, time of disease follow-up, time of treatment with the drug, previous adjuvant/neoadjuvant, presence of RAS type mutation and number of previous metastatic lines. Efficacy was determined by calculating progression free survival (PFS) applying the Kaplan-Meyer statistic with SPSS V.15. Progression was analysed according to the radiological criteria response evaluation criteria in solid tumours (RECIST V.1.1). The occurrence of grade III/IV adverse effects (AEs) leading to early dose reduction/suspension of treatment was determined. AEs were classified according to the common terminology criteria for adverse effects (CTCAE V.6.0). Results 104 patients were included, 57.7% (n=60) treated with REG (66.3%, n=69); mean age was 63.9 years (41-83)). Mean follow-up time of the disease was 3.9 years (0.1-15.5). Mean duration of treatment was 3.9 months for TAS-102 and 4.2 for REG. 46% (n=48) of patients received adjuvant therapy and 16.3% (n=17) neoadjuvant. 48.1% presented RAS mutation (n=50). Mean of previous metastatic lines was 2.4 (1-7). 84% (n=37) of patients progressed with TAS-102 versus 72% (n=43) with REG. 11.5% (n=12) discontinued treatment due to toxicity. Median PFS was the same for both: 3.8 months (p=0.86). A reduction in drug doses due to the appearance of AEs was carried out in 25% of cases (n=11) with TAS-102 versus 61.7% with REG (n=37). The most common grade III/IV AEs with TAS-102 were haematological toxicity (20.5%, n=9), gastrointestinal (2.3%, n=1) and other (2.3%, n=1); for REG, gastrointestinal (16.7%, n=10), asthenia (13.3%, n=8), skin toxicity (11.7%, n=7), mucositis (6.7%, n=4), plaquetopenia (3.3%, n=2) and other (13.3%, n=8). Conclusion and relevance The study showed that there were no significant differences between PFS values between TAS-102 and REG. However, treatment with REG was tolerated worse, with AEs in more than 60% of cases compared with 25% with TAS-102.