Randomised phase-2 screening trial of intermittent energy restriction plus resistance exercise versus resistance exercise alone during chemotherapy for advanced breast cancer

BACKGROUND: Weight control and energy restriction could improve survival in patients with advanced breast cancer (ABC) but randomised data are lacking. A randomised screening trial was conducted to assess an intermittent energy restricted diet and resistance exercise intervention (IER + RE) vs RE alone (RE) on progression free survival (PFS), toxicity and Quality of Life (QoL) during chemotherapy for ABC. METHODS: Sixty-eight women were randomised to IER + RE (n = 35) or RE (n = 33) with one-sided significance assessed at the 20% threshold. The primary end point was PFS secondary endpoints included chemotherapy toxicity, weight change and QoL. RESULTS: The adjusted hazard rate for progression comparing IER + RE vs RE was 0.729 (0.391-1.361) and the median PFS 42.0 vs 26.1 weeks respectively (p = 0.160). Toxicity was low and comparable between groups. Comparing IER + RE vs RE alone at cycle 3 the median (interquartile range) changes were: weight -1.8 kg (-4.2 to -0.7) vs +0.2 kg (-0.74, 2.59) (p < 0.001), FACT-B + 4.0 (-0.8, 11) vs +1.0 (-4.0, 4.0) (p = 0.031) and Hospital Anxiety Depression Score -2.0 (-3.5, +0.5) vs +1.0 (-2, 3.5) (p = 0.022). CONCLUSION: IER + RE improved PFS and QoL without evidence of harms warranting a further larger randomised study in ABC. TRIAL REGISTRATION: https://www.isrctn.com/ISRCTN12841416 .