A Study Assessing Adverse Events and Disease Activity When Comparing Intravenously (IV) Infused ABBV-400 to Trifluridine and Tipiracil (LONSURF) Oral Tablets Plus IV Infused Bevacizumab in Adult Participants With c-Met Protein Above Cutoff Level Above Refractory Metastatic Colorectal Cancer

Colorectal cancer (CRC) is the third most common type of cancer diagnosed worldwide and in China. The purpose of this study is to assess adverse events disease activity when comparing intravenously (IV) infused telisotuzumab adizutecan to trifluridine and tipiracil (LONSURF) oral tablets plus IV infused bevacizumab in adult participants with c-Met protein above cutoff level refractory metastatic colorectal cancer (mCRC). Telisotuzumab adizutecan is an investigational drug being developed for the treatment of CRC. Participants are put into treatment arms as part of 2 stages. Each treatment arm in stage 1 receives a different dose of telisotuzumab adizutecan. Each treatment arm in stage 2 receives the optimal dose of telisotuzumab adizutecan or LONSURF plus bevacizumab. Up to approximately 460 adult participants with c-Met protein above cutoff level refractory mCRC, will be enrolled in the study in approximately 160 sites in 15-20 countries. In stage 1, participants will receive intravenously (IV) infused telisotuzumab adizutecan dose A or B. In stage 2, participants will receive the optimal dose of IV infused telisotuzumab adizutecan or the standard of care (SOC), LONSURF oral tablets plus IV infused bevacizumab. The total study duration will be approximately 4 years. There may be higher treatment burden for participants in this trial compared to their standard of care. Participants will attend regular visits during the study at an approved institution (hospital or clinic). The effect of the treatment will be frequently checked by medical assessments, blood tests, questionnaires and side effects.

Inclusion Criteria: * Life expectancy \>= 12 weeks per investigator assessment. * Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0 or 1 during the screening period prior to the first dose of the study drug. * Measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1. Exclusion Criteria: * Prior systemic regimen containing c-MET targeting antibody/bispecific or Antibody Drug Conjugate (c-Met targeting Antibody Drug Conjugate \[ADC\]). * History of allergic reactions or hypersensitivity to bevacizumab or any of its excipients, or to compounds similar to trifluridine/tipiracil. * Active infection as noted in the protocol.