Poster Presentation Clinical Oncology Society of Australia Annual Scientific Meeting 2018

A randomised open-label phase 2 trial of consolidation with nivolumab and ipilimumab in limited-stage SCLC after concurrent chemo-radiotherapy (STIMULI) (#423)

Paul Mitchell 1 , Antony Mersiades 2 , Jenna Mitchell 2 , Solange Peters 3 4 , Dirk de Ruysscher 3 5 , Martin Stockler 2 , Rolf A Stahel 3 6
  1. Olivia Newton-John Cancer and Wellness Centre, Austin Health, Melbourne, VIC, Australia
  2. NHMRC Clinical Trials Centre, University of Sydney, Camperdown, NSW, AUSTRALIA
  3. European Thoracic Oncology Platform (ETOP), Bern, Switzerland
  4. Department of Oncology, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland
  5. Department of Radiation Oncology, Maastro Clinic, Maastricht, Netherlands
  6. Clinic of Oncology, University Hospital Zürich, Zürich, Switzerland

Background

Long-term outcomes for patients with limited-disease small cell lung cancer (LD-SCLC) remain poor, with a median survival of 2-years and 5-year survival rates of around 25%, with both distant metastases and local recurrence remaining problematic after concurrent chemoradiotherapy and prophylactic cranial irradiation (PCI).  In a phase II trial immune-checkpoint blockade combining ipilimumab with nivolumab for the treatment of recurrent SCLC has shown promising efficacy signals with an overall response rate of 33% in heavily pre-treated SCLC, with durable responses and an acceptable toxicity profile.  Consolidation therapy using the PD-L1 antibody durvalumab demonstrated improved progression free and overall survival in non-small cell lung cancer (NSCLC) following concurrent chemoradiotherapy.  Consolidation therapy using nivolumab in combination with ipilimumab may improve survival outcomes for LD-SCLC.

Methods

This international, open-label randomised phase 2 trial will enrol 325 patients with newly diagnosed LD-SCLC and aims to randomise 260 patients.  Upon completion of platinum etoposide chemotherapy, concurrent thoracic radiotherapy then PCI, patients without disease progression will be randomised 1:1 to receive consolidation with nivolumab (1mg/kg) and ipilimumab (3mg/kg IV q3 weeks for 4 cycles) followed by nivolumab (240mg IV q2 weeks for up to 12 months), or observation alone.  Major trial endpoints include overall survival (OS) and progression-free survival (PFS) (co-primary), objective response, time to treatment failure, and adverse events.  Imaging will be performed every 9 weeks until 18 months, then every 12 weeks until 2 years, every 6 months until 4 years, and at 5 years.

STATUS (as of 8 Aug 2018): In Australia, HREC approval received, sites preparing for site activation. Australia to recruit 50 patients from 25 sites. Internationally, 192 patients enrolled/112 randomised.

STIMULI is a cooperative group trial sponsored by the ETOP and coordinated in collaboration with the ALTG and NHMRC CTC, University of Sydney with support from Bristol Myers Squibb.