Clinical practice use of panitumumab combined with chemotherapy in patients with wild-type RAS metastatic colorectal cancer.

Abstract

852 Background: This study aimed to understand panitumumab (pmab) use in clinical practice for patients with wild-type RAS metastatic colorectal cancer (mCRC), in first-line (1L) with FOLFOX or second-line (2L) with FOLFIRI following fluoropyrimidine-based chemotherapy (excl. irinotecan). Methods: This is a combined analysis of two observational, non-interventional prospective cohort studies conducted in Germany/France (2012-2016) and Bulgaria/Czech Republic/Hungary (2013-2016). Results: Results are presented in the order of 1L FOLFOX (n = 332) followed by 2L FOLFIRI (n = 94). Patients received a median of 10 and 11.5 pmab infusions. The median duration of pmab exposure was 5.7 and 6.9 months (note that 53 and 10 patients continued pmab use after study end). The unadjusted overall response rate (complete or partial response) was 42% and 29%, based on 45% and 44% of patients with available response data post-baseline. In the 1L setting, resectability was achieved in 9%, not achieved in 42%, and unknown in 48%. Hospitalizations were reported for 100% and 99%, mostly cancer-related visits such as scheduled anticancer treatment (e.g. chemotherapy/pmab administrations), tumor assessment visits, or interventions; 93% in both groups reported outpatient, 66% and 60% inpatient visits. Conclusions: Overall, the study results show that treatment patterns and clinical efficacy of pmab in routine clinical practice were comparable to randomized controlled trials (RCTs). The ADR/SADR skin toxicity events are lower than expected based on findings from RCTs, however, similar findings have been shown in a previous observational study. More investigation is required to understand the reason for this.[Table: see text]