{"entity":{"id":"rtog-0415","kind":"trial","name":"RTOG 0415","aka":["RTOG 0415","NRG Oncology RTOG 0415"],"tldr":"Showed that men with low-risk prostate cancer can have five and a half weeks of radiotherapy instead of eight without losing control of the cancer, at the price of slightly more bowel and bladder trouble later.","summary":"RTOG 0415 randomised 1,115 men with low-risk prostate cancer 1:1 to conventional radiotherapy (73.8 Gy in 41 fractions over 8.2 weeks) or hypofractionated radiotherapy (70 Gy in 28 fractions over 5.6 weeks). The trial was designed to establish that hypofractionation did not reduce 5-year disease-free survival by more than 7.65 percent, a hazard ratio below 1.52.\n\nOf 1,092 protocol-eligible men with follow-up, 542 received conventional and 550 hypofractionated treatment. At a median 5.8 years, estimated 5-year disease-free survival was 85.3 percent (95 percent confidence interval 81.9 to 88.1) with conventional treatment and 86.3 percent (83.1 to 89.0) with hypofractionation, hazard ratio 0.85 (0.64 to 1.14), meeting non-inferiority (p<0.001).\n\nThe cost was measurable: late grade 2 and 3 gastrointestinal and genitourinary adverse events were increased with hypofractionation, hazard ratios 1.31 to 1.59. That is the trade-off hypofractionation has consistently shown, and it is why a man with poor urinary function at baseline is often steered towards a longer course.","status":"positive","asOf":"2026-09-25","links":[{"label":"ClinicalTrials.gov NCT00331773","url":"https://clinicaltrials.gov/study/NCT00331773"},{"label":"RTOG 0415 (Journal of Clinical Oncology 2016)","url":"https://doi.org/10.1200/JCO.2016.67.0448"}],"tags":[],"related":[],"cancers":["prostate","prostate-low-risk"],"sections":[],"technologies":["hypofractionated-radiotherapy","imrt-igrt"],"targets":[],"drugs":[],"companies":["nrg-oncology"],"institutions":[],"pathways":[],"terms":["hypofractionation","curative-intent","psa"],"trials":["chhip","profit-trial","hypo-rt-pc","pace-b"],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"nct":"NCT00331773","phase":"3","setting":"Low-risk localised prostate cancer: hypofractionated radiotherapy, 70 Gy in 28 fractions over 5.6 weeks, against conventional radiotherapy, 73.8 Gy in 41 fractions over 8.2 weeks, with 5-year disease-free survival as the primary endpoint and a non-inferiority design","sponsor":"Radiation Therapy Oncology Group, now NRG Oncology, funded by the National Cancer Institute","result":"Five-year disease-free survival 86.3 percent with 70 Gy in 28 fractions against 85.3 percent with 73.8 Gy in 41 fractions (hazard ratio 0.85, 95 percent confidence interval 0.64 to 1.14), non-inferior; late grade 2 to 3 bowel and bladder events increased (hazard ratios 1.31 to 1.59).","yearReported":2016,"enrolled":1115,"enrolledBasis":"randomised","enrolledNote":"1,115 men were randomised and 1,092 were protocol-eligible with follow-up information; the analysed figure is the one quoted in the results.","outcomes":[{"endpoint":"Disease-free survival at 5 years","primary":true,"unit":"%","arms":[{"name":"Hypofractionated, 70 Gy in 28 fractions","n":550,"value":86.3},{"name":"Conventional, 73.8 Gy in 41 fractions","n":542,"value":85.3}],"hr":0.85,"ci":[0.64,1.14],"p":"<0.001 for non-inferiority","source":"https://doi.org/10.1200/JCO.2016.67.0448"}],"replication":"CHHiP (3,216 men) and PROFIT (1,206 men) reached the same conclusion for moderate hypofractionation in intermediate-risk disease; HYPO-RT-PC and PACE-B extended it to five or seven fractions."},"route":"/trials/rtog-0415/","neighbours":{"cancer":[{"id":"prostate-low-risk","kind":"cancer","name":"Localised prostate cancer, very low and low risk","route":"/cancers/prostate-low-risk/"},{"id":"prostate","kind":"cancer","name":"Prostate cancer","route":"/cancers/prostate/"}],"technology":[{"id":"hypofractionated-radiotherapy","kind":"technology","name":"Hypofractionated radiotherapy","route":"/technologies/hypofractionated-radiotherapy/"},{"id":"imrt-igrt","kind":"technology","name":"IMRT / IGRT (modern external beam)","route":"/technologies/imrt-igrt/"}],"company":[{"id":"nrg-oncology","kind":"company","name":"NRG Oncology","route":"/companies/nrg-oncology/"}],"term":[{"id":"curative-intent","kind":"term","name":"Curative intent vs palliative intent","route":"/terms/curative-intent/"},{"id":"prostate-radiotherapy-fractionation","kind":"term","name":"How many radiotherapy visits: the prostate fractionation trials","route":"/terms/prostate-radiotherapy-fractionation/"},{"id":"hypofractionation","kind":"term","name":"Hypofractionation (fewer, larger radiotherapy doses)","route":"/terms/hypofractionation/"},{"id":"psa","kind":"term","name":"PSA (prostate-specific antigen)","route":"/terms/psa/"}],"trial":[{"id":"chhip","kind":"trial","name":"CHHiP","route":"/trials/chhip/"},{"id":"hypo-rt-pc","kind":"trial","name":"HYPO-RT-PC","route":"/trials/hypo-rt-pc/"},{"id":"pace-b","kind":"trial","name":"PACE-B","route":"/trials/pace-b/"},{"id":"profit-trial","kind":"trial","name":"PROFIT (Prostate Fractionated Irradiation Trial)","route":"/trials/profit-trial/"}]}}