A Clinical Study of Zilovertamab Vedotin (MK-2140) Plus Rituximab Plus Cyclophosphamide, Doxorubicin, and Prednisone (R-CHP) Versus Polatuzumab Vedotin Plus R-CHP in People With Diffuse Large B-cell Lymphoma (DLBCL) (MK-2140-011/waveLINE-011)

Researchers are looking for ways to treat germinal center B-cell-like diffuse large B-cell lymphoma (GCB DLBCL). DLBCL is a fast-growing blood cancer that affects B-cells. GCB is a type of DLBCL that affects young B-cells that are still maturing. The goal of this study is to learn if more people who receive zilovertamab vedotin (MK-2140) and R-CHP have the cancer respond (go away) than those who receive polatuzumab vedotin and R-CHP.

Inclusion Criteria: The main inclusion criteria include but are not limited to the following: * Has histologically confirmed diagnosis of germinal center B-cell (GCB) subtype of diffuse large B-cell lymphoma (DLBCL), by prior biopsy, according to the World Health Organization (WHO) classification of neoplasms of the hematopoietic and lymphoid tissues. * Has positron emission tomography (PET) positive disease at screening, defined as 4 to 5 on the Lugano 5-point scale. * Has received no prior treatment for their DLBCL. * Human immunodeficiency virus (HIV) infected participants must have well controlled HIV on antiretroviral therapy (ART). * Participants who are hepatitis B surface antigen (HBsAg) positive are eligible if they have received hepatitis B virus (HBV) antiviral therapy and have undetectable HBV viral load prior to randomization. * Participants with history of hepatitis C virus (HCV) infection are eligible if HCV viral load is undetectable at screening. Exclusion Criteria: The main exclusion criteria include but are not limited to the following: * Has a history of transformation of indolent disease to DLBCL. * Has received a diagnosis of primary mediastinal B-cell lymphoma (PMBCL) or Grey zone lymphoma. * Has Ann Arbor Stage I DLBCL. * Has clinically significant (i.e., active) cardiovascular disease: cerebral vascular accident/stroke (\