Amendment 1, dated 29 August 2019, proposed one clarification and two changes to the inclusion/exclusion criteria, the latter in order to align with other studies and with clinical practice. Moreover, it stipulated that oxaliplatin and LV should be administered in sequence or in two different injection ports.

Amendment 2, dated 20 February 2020, included more information on non-clinical data related to arfolitixorin, the specification of DoR as a secondary endpoint, the inclusion of RFS for patients undergoing metastatic resection as an exploratory endpoint, and several clarifications about data entry, stratification, inclusion criteria, calculation of body surface area, use of bevacizumab biosimilars and further explanations about study treatment, PK sampling, ECG, and the management of patients becoming eligible for metastasis resection. Moreover, the collection of baseline KRAS, BRAF, NRAS mutations was added to the eCRF at screening, when available, to allow for subgroup analyses; the planned OS analysis section was updated following a request from the US Food and Drug Administration; and the work of the DSMB was further detailed, following the decision to follow the recommendation of Japanese authorities regarding the number of patients to be enrolled from Japan.

Amendment 3, dated 20 August 2021, provided several clarifications, including those about the timing of ORR and PFS analysis, the mechanism of action of arfolitixorin, on the planned PK assessment, on the management of patients with QTcF prolongation, as well as several changes to ensure that the protocol text, the SAP and the DSMB charter were aligned. Moreover, the final list of genes of interest for the pharmacogenetic analyses was provided in this amendment.

Amendment 4, dated 22 February 2022 was not submitted, and the changes proposed in this amendment were eventually included in protocol version 6.0. The main change was the sample size (from 440 patients to 490 patients, to account for enrollment of additional Japanese patients) and corresponding recruitment period and impact on analysis of ORR, as well as the number of required PFS events (from 300 to 230, see explanation in Section 9.7.1) and expected impact on analysis. Moreover, minor editorial changes were undertaken, and updates were provided in light of the latest version (14.0) of the Investigator’s Brochure, the statistical section was updated in accordance with the current version of the SAP, and the phone number for the Sponsor’s Chief Medical Officer was updated.

Amendment 5, dated 22 April 2022, included one additional change to the required number of PFS events (to at least 235, to align with the SAP and with feedback from regulatory authorities), and the inclusion of the ITT excluding additional Japanese patients (ITTE) analysis set, to be in line with the current SAP.