Background: Nivolumab (NIVO), a programmed death-1 immune checkpoint inhibitor, has demonstrated clinical efficacy across patients with different tumor types, including clear cell renal cell carcinoma (ccRCC), when administered via IV infusion. As an alternative to IV infusion, subcutaneous (SC) administration alleviates the need for IV ports, thereby lowering the risk of associated complications such as infections and phlebitis. SC formulation also reduces the time for dose preparation and administration, which may decrease overall treatment burden and reduce patient time in the clinic, benefiting patients and healthcare providers and improving overall healthcare resource utilization. SC-administered NIVO consists of NIVO co-formulated with the recombinant human hyaluronidase PH20 enzyme (NIVO + rHuPH20), which aims to increase the dispersion and absorption of NIVO within the SC space. SC NIVO + rHuPH20 was shown to be safe and well tolerated in a phase 1/2 study, warranting further investigation (Lonardi S et al. J Clin Oncol 2021;39(suppl 15):2575). Methods: CheckMate 67T is a multicenter, randomized, open-label, phase 3 study that will evaluate the noninferiority of SC NIVO + rHuPH20 versus IV NIVO in patients with advanced or metastatic ccRCC who have progressed after receiving ≤ 2 prior systemic treatment regimens. Key inclusion criteria are age ≥ 18 years, histologically confirmed advanced or metastatic ccRCC, measurable disease by RECIST v1.1 within 28 days prior to randomization, and a Karnofsky performance status ≥ 70. Key exclusion criteria are untreated symptomatic metastases to the central nervous system, other malignancy, autoimmune diseases, HIV-positive status with AIDS-defining infection within past year or current CD4 count < 350 cells/μL, other serious or uncontrolled disorders including severe, acute SARS-CoV-2 infection, and prior treatment with immune checkpoint inhibitors, other T-cell–targeting antibody drugs, or live attenuated vaccines within 30 days of first study treatment. At least 454 eligible patients will be randomized to receive SC NIVO + rHuPH20 or IV NIVO. The primary objectives are to demonstrate pharmacokinetic (PK) noninferiority of SC NIVO versus IV NIVO, as measured by time-averaged serum concentration over the first 28 days (Cavgd28) and trough serum concentration at steady state (Cminss) (co-primary endpoints). Secondary endpoints include objective response rate by blinded independent central review, additional PK parameters, safety, efficacy, and immunogenicity of SC NIVO and IV NIVO. This study is currently enrolling patients globally. Clinical trial information: NCT04810078.