ATOMICC trial: a randomized, open-label, phase II trial of anti-PD1, dostarlimab, as maintenance therapy for patients with high-risk locally advanced cervical cancer after chemoradiation.

Background: Currently, women diagnosed with high-risk locally advanced cervical cancer are at high risk of recurrence after treatment with concurrent chemoradiation and represent a population with high unmet need.

Primary Objective: The primary objective is to evaluate the progression-free survival of high-risk locally advanced cervical cancer patients who have achieved a partial or complete response after chemoradiation after receiving dostarlimab as maintenance therapy.

Study Hypothesis: The study aims to demonstrate that the use of dostarlimab, as maintenance therapy, would significantly increase progression-free survival in these patients.

Trial Design: ATOMICC trial is a phase II, randomized, open-label, multicenter study to assess the efficacy and safety of anti-PD1, dostarlimab, as maintenance therapy in patients with high-risk locally advanced cervical cancer who have achieved a partial or complete response after chemoradiation. The control arm entails a clinical and radiological follow-up, with no further treatment (current standard of care). ATOMICC trial is an investigator-driven trial sponsored by GEICO (Grupo Español de Investigación en Cáncer de Ovario) and supported by GlaxoSmithKline (GSK).

Major Inclusion/exclusion Criteria: Women aged over 18 years with a biopsy-confirmed squamous cell carcinoma, adenocarcinoma, or adenosquamous carcinoma of the cervix meeting the following staging criteria: International Federation of Gynecology and Obstetrics (FIGO) 2009 stages IB2, IIA2, IIB with pelvic lymph node involvement, FIGO stages IIIA, IIIB, IVA, and any FIGO 2009 stage with para-aortic lymph node involvement are eligible for the trial. All patients must have achieved a partial or complete response after definitive concurrent chemoradiation. Women diagnosed with FIGO stage IVB, having undergone a previous hysterectomy, or having a history of active autoimmune disease will not be considered eligible.

Primary Endpoint: Progression-free survival defined as the time from the date of randomization to the date of first disease progression or death due to any cause, whichever occurs first.

Sample Size: A total of 132 patients are expected to be recruited in the study, using a 1:2 (control:experimental arm) randomization allocation ratio.

Estimated Dates For Completing Accrual And Presenting Results: The trial was launched in Q2-2019 and the trial is estimated to be closed for recruitment in Q3-2022. Results are expected to be released in Q3-2024.

Trial Registration: The trial is registered at ClinicalTrials.gov (NCT03833479).