Eastern Cooperative Oncology Group (ECOG) performance status of =< within days prior to step registration Eastern Cooperative Oncology Group (ECOG) performance status - days prior to registration Eastern Cooperative Oncology Group (ECOG) status - within month prior to registration Eastern Cooperative Oncology Group (ECOG) performance status of - within days of enrollment Eastern Cooperative Oncology Group (ECOG) performance status of or within days prior to registration Has an Eastern Cooperative Oncology Group (ECOG) performance status of to within days prior to the start of study treatment. Patients must exhibit an Eastern Cooperative Oncology Group (ECOG), performance status of - =< days prior to registration Have an Eastern Cooperative Oncology Group (ECOG) performance status of to within days of randomization. Has an Eastern Cooperative Oncology Group (ECOG) performance status of or within days of study start Has an Eastern Cooperative Oncology Group (ECOG) performance status of , , or within days prior to study registration. Eastern Cooperative Oncology Group (ECOG) performance status (asymptomatic to symptomatic but capable of self-care) within days prior to randomization Eastern Cooperative Oncology Group (ECOG)/Karnofsky performance status of , , or within days prior to registration Eastern Cooperative Oncology Group (ECOG) performance status - within days prior to registration Eastern Cooperative Oncology Group (ECOG) performance status of - within days prior to being registered for protocol therapy Eastern Cooperative Oncology Group (ECOG) performance status - assessed within days of enrollment Have an Eastern Cooperative Oncology Group (ECOG) performance status of to . Evaluation of ECOG is to be performed within days prior to the date of allocation/randomization Eastern Cooperative Oncology Group (ECOG) performance status of =< within days prior to registration. Cisplatin-ineligible chemotherapy-naive subjects may have an ECOG performance status of =< . Eastern Cooperative Oncology Group (ECOG) performance status of or (within days prior to enrollment) Eastern Cooperative Oncology Group (ECOG) performance status of - within days prior to being registered for protocol therapy Eastern Cooperative Oncology Group (ECOG) status of , , or within days prior to registration Eastern Cooperative Oncology Group (ECOG) performance status of or (must be done within days prior to study drug administration) Eastern Cooperative Oncology Group (ECOG) performance status of , or within days prior to randomization Eastern Cooperative Oncology Group (ECOG) performance status of or within days prior to registration for protocol therapy Eastern Cooperative Oncology Group (ECOG) performance status of =< within days prior to registration Eastern Cooperative Oncology Group (ECOG) performance status of =< within days prior to being registered for protocol therapy Clinical performance status of Eastern Cooperative Oncology Group (ECOG) - within days of signing informed consent Patient has an Eastern Cooperative Oncology Group (ECOG) performance status of - within days of registration Eastern Cooperative Oncology Group (ECOG) performance status must be level or within days prior to registration Clinical performance status of Eastern Cooperative Oncology Group (ECOG) - within days of signing informed consent (Turnstile I) Clinical performance status of Eastern Cooperative Oncology Group (ECOG) - within days of signing informed consent (Turnstile I) Eastern Cooperative Oncology Group (ECOG) performance status of - within days prior to registration Eastern Cooperative Oncology Group (ECOG) status - documented within days of registration Eastern Cooperative Oncology Group (ECOG) performance status or within days prior to registration for protocol therapy Eastern Cooperative Oncology Group (ECOG) performance status of , or within days prior to registration Eastern Cooperative Oncology Group (ECOG) performance status of or within days prior to the first dose of study treatment but before randomization. REGISTRATION TO TREATMENT (STEP ): Patients have an Eastern Cooperative Oncology Group (ECOG) performance status of - Eastern Cooperative Oncology Group (ECOG) performance status of - within days prior to registration Eastern Cooperative Oncology Group (ECOG) performance status of or within days prior to registration for protocol therapy Eastern Cooperative Oncology Group (ECOG) performance status of - within days prior to registration. Performance status (Eastern Cooperative Oncology Group [ECOG]/Karnofsky) of , or within days prior to registration Eastern Cooperative Oncology Group (ECOG) performance status of or within days before registration for protocol therapy Eastern Cooperative Oncology Group (ECOG) performance status of or within days prior to study start Eastern Cooperative Oncology Group (ECOG) performance status of or within days prior to study start Eastern Cooperative Oncology Group (ECOG) performance status of , , or within days prior to randomization. Patients must have an Eastern Cooperative Oncology Group (ECOG) performance status of , , , or within days prior to registration Clinical performance status of Eastern Cooperative Oncology Group (ECOG) - within days of signing informed consent Eastern Cooperative Oncology Group (ECOG) performance status of within days prior to study registration Patients must have an Eastern Cooperative Oncology Group (ECOG) performance status of , , or (Karnofsky >= %) within days prior to registration PRE-REGISTRATION INCLUSION CRITERIA: Eastern Cooperative Oncology Group (ECOG) performance status =< Has Eastern Cooperative Oncology Group (ECOG) performance status of or performed within days of treatment initiation. Eastern Cooperative Oncology Group (ECOG) performance status of , , or within days prior to registration Eastern Cooperative Oncology Group (ECOG) performance status of or within days prior to registration for protocol therapy Eastern Cooperative Oncology Group (ECOG) Performance Status of or within days prior to registration. Eastern Cooperative Oncology Group (ECOG) performance status of or within days before enrollment. Eastern Cooperative Oncology Group (ECOG) performance status of or within days before enrollment. Have an Eastern Cooperative Oncology Group (ECOG) performance status of or within days prior to the initiation of study treatment Eastern Cooperative Oncology Group (ECOG) performance status of =< within days prior to dose of mirvetuximab soravtansine Eastern Cooperative Oncology Group (ECOG) performance status of , or within days prior to first dose of study drug. Eastern Cooperative Oncology Group (ECOG) performance status of , or within days prior to first dose of study treatment. Clinical performance status of Eastern Cooperative Oncology Group (ECOG) - within days of signing informed consent Has Eastern Cooperative Oncology Group (ECOG) performance status of or performed within days prior to receiving the first dose of study therapy Eastern Cooperative Oncology Group (ECOG) performance status of to within days prior to initiation of treatment Eastern Cooperative Oncology Group (ECOG) performance status - (within days of enrollment) Eastern Cooperative Oncology Group performance status of or as assessed within days prior to randomization. Eastern Cooperative Oncology Group (ECOG) performance status of =< within days prior to registration Eastern Cooperative Oncology Group (ECOG) performance status of - within days of registration Eastern Cooperative Oncology Group (ECOG) performance status of =< within days prior to being registered for protocol Has an Eastern Cooperative Oncology Group (ECOG) performance status of or , as assessed within days prior to the start of study drug.