Anti-PD-L1 (atezolizumab) as an immune primer and concurrently with extended-field chemoradiotherapy for node-positive locally advanced cervical cancer

BackgroundThere is a lack of data exploring the use and optimal timing of immunotherapy and chemoradiation therapy (CRT) in node-positive cervical cancer. Further translational research into mechanisms of response and resistance to immunotherapy in advanced cervical cancer is warranted.Primary objectivesTo determine if sequencing of atezolizumab and CRT result in differential immune activation, as determined by clonal expansion of T cell receptor beta (TCRB) repertoires in peripheral blood on day 21.Study hypothesisThere is a difference for clonal expansion of T cell receptor beta repertoires in the peripheral blood at day 21 between the priming and concurrent atezolizumab and CRT in Arm A vs the concurrent atezolizumab and CRT in Arm B.Trial designLocally advanced cervical cancer patients with lymph node-positive disease will be randomized on this open-label, randomized trial with two experimental arms. Arm A will get one dose of atezolizumab prior to cisplatin CRT, and then two subsequent doses of atezolizumab during the CRT, and Arm B will get three doses during CRT. Patients will be followed for 2 years to assess outcomes.Major inclusion/exclusion criteriaPatients must have histologically confirmed, newly diagnosed advanced cervical cancer (squamous cell carcinoma, adenocarcinoma, and adenosquamous cell carcinoma): FIGO 2009 clinical stages IB2/IIA with positive para-aortic nodes, or FIGO 2009 clinical stages IIB/IIIB/IVA with positive pelvic or para-aortic lymph nodes. Exclusion criteria include those who had a prior hysterectomy or lymph node dissection.Primary endpointsClonal expansion of TCRB) repertoires in peripheral blood on day 21.Sample sizeThe sample size will be 40 patients.Estimated dates for completing accrual and presenting resultsWe estimate accrual to finish by the summer of 2020 with presentation of results to follow in 2021.Trial registrationNCT03738228