BackgroundImmunoPET is a multicentre, single arm, phase 0–1 study that aims to establish if⁸⁹Zr-durvalumab PET/CT can be used to interrogate the expression of PD-L1 in larger, multicentre clinical trials.MethodsThe phase 0 study recruited 5 PD-L1+ patients with metastatic non-small cell lung cancer (NSCLC). Patients received 60MBq/70 kg⁸⁹Zr-durva up to a maximum of 74 MBq, with scan acquisition at days 0, 1, 3 or 5±1 day. Data on (1) Percentage of injected⁸⁹Zr-durva dose found in organs of interest (2) Absorbed organ doses (µSv/MBq of administered⁸⁹Zr-durva) and (3) whole-body dose expressed as mSv/100MBq of administered dose was collected to characterise biodistribution.The phase 1 study will recruit 20 patients undergoing concurrent chemoradiotherapy for stage III NSCLC. Patients will have⁸⁹Zr-durva and FDG-PET/CT before, during and after chemoradiation. In order to establish the feasibility of⁸⁹Zr-durva PET/CT for larger multicentre trials, we will collect both imaging and toxicity data. Feasibility will be deemed to have been met if more than 80% of patients are able complete all trial requirements with no significant toxicity.Ethics and disseminationThis phase 0 study has ethics approval (HREC/65450/PMCC 20/100) and is registered on the Australian Clinical Trials Network (ACTRN12621000171819). The protocol, technical and clinical data will be disseminated by conference presentations and publications. Any modifications to the protocol will be formally documented by administrative letters and must be submitted to the approving HREC for review and approval.Trial registration numberAustralian Clinical Trials Network ACTRN12621000171819.