{"entity":{"id":"mr-and-biology-guided-radiotherapy-roadmap","kind":"roadmap","name":"MR-linacs and biology-guided radiotherapy: from a cobalt MRI machine to PET-guided beams","aka":[],"tldr":"Machines that watch the tumour while treating it: first with MRI inside the treatment machine, then with a PET scanner that steers the beam from the tumour's own signal. Dated from the FDA records.","summary":"ViewRay's first system, cleared in May 2012 (K111862), combined MRI with three cobalt-60 sources. The MRIdian Linac replaced cobalt with a linac in 2017 (K162393) and was redesigned in 2021 (K212958). Elekta Unity, a 7 MV linac rotating around a 1.5 tesla MRI, was cleared in December 2018 (K182076) with MRIdian as predicate. ViewRay filed for Chapter 11 in July 2023; ViewRay Systems, established in February 2024 after acquiring its assets, sells the MRIdian A3i. RefleXion's X1 was cleared in 2020 (K190978) and its PET-guided SCINTIX therapy by De Novo in February 2023 (DEN220014) for lung and bone tumours, and the X2 (K252071, December 2025) widened the PET field of view from 5.3 to 21.5 cm.","asOf":"2026-11-04","links":[{"label":"FDA 510(k) K111862: ViewRay System (22 May 2012)","url":"https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K111862"},{"label":"FDA 510(k) K162393: MRIdian Linac System (24 February 2017)","url":"https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K162393"},{"label":"FDA 510(k) K212958: MRIdian Linac System (14 December 2021)","url":"https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K212958"},{"label":"FDA 510(k) K182076: Elekta Unity (4 December 2018)","url":"https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K182076"},{"label":"FDA 510(k) K190978: RefleXion Medical Radiotherapy System (12 March 2020)","url":"https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K190978"},{"label":"FDA De Novo DEN220014: fludeoxyglucose F18-guided radiation therapy system (RefleXion)","url":"https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/denovo.cfm?id=DEN220014"},{"label":"FDA 510(k) K252071: RefleXion X2 (18 December 2025)","url":"https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K252071"},{"label":"ViewRay Systems: investors page (assets of ViewRay, Inc. acquired; company established 6 February 2024)","url":"https://viewraysystems.com/investors/"}],"tags":["machines-wave3"],"related":["linac-machines-roadmap","radiation-roadmap","idea-fund-adaptive-radiotherapy-evidence"],"cancers":[],"sections":["radiation","devices"],"technologies":["mr-linac","biology-guided-radiotherapy","adaptive-radiotherapy","respiratory-gating-tumour-tracking-systems"],"targets":[],"drugs":[],"companies":["viewray","elekta","reflexion"],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":["b-surgery-radiation-innovation"],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"provenance":{"editedBy":"OnCo machines inventory (openFDA, accessdata.fda.gov, ClinicalTrials.gov v2, Europe PMC, maker pages)","editedOn":"2026-11-04"},"steps":[{"era":"2012-2016","title":"MRI with cobalt","description":"The ViewRay System (K111862, May 2012) paired a low-field MRI with three cobalt-60 heads so soft tissue could be seen during treatment. Cobalt limited beam sharpness and dose rate.","refs":["mr-linac","viewray","cobalt-60-teletherapy"],"status":"historic"},{"era":"2017-2021","title":"MR-linacs","description":"The MRIdian Linac (K162393, February 2017) replaced cobalt with a linac; Elekta Unity (K182076, December 2018) put a 7 MV linac around a 1.5 tesla MRI. Daily online adaptation and gating on soft tissue became routine at the centres that bought them, and MIRAGE showed less toxicity with MR-guided prostate stereotactic treatment.","refs":["mr-linac","elekta","viewray","adaptive-radiotherapy"],"status":"historic"},{"era":"2023-2024","title":"Bankruptcy and a new owner","description":"ViewRay filed for Chapter 11 in July 2023. ViewRay Systems, established on 6 February 2024 after acquiring the assets, designs, makes and sells the MRIdian A3i, described as adding brain treatment and real-time 3D tissue tracking.","refs":["viewray","mr-linac"],"status":"current"},{"era":"2020-2026","title":"PET-guided beams","description":"RefleXion's X1 (K190978, 2020) added a PET subsystem to a ring linac; its SCINTIX biology-guided therapy was authorised by De Novo in February 2023 (DEN220014) for tumours in lung and bone, creating a new device type. The X2 (K252071, December 2025) uses four detector rows instead of one, widening the PET field from 5.3 to 21.5 cm.","refs":["biology-guided-radiotherapy","reflexion","pet-ct"],"status":"current"},{"era":"Next","title":"Proving the benefit","description":"Throughput and cost limit both approaches, and whether daily adaptation improves cure rather than only toxicity is still being tested. A coordinated evidence programme for adaptive radiotherapy is proposed in OnCo.","refs":["idea-fund-adaptive-radiotherapy-evidence","b-surgery-radiation-innovation"],"status":"emerging"}],"watch":[]},"route":"/roadmaps/mr-and-biology-guided-radiotherapy-roadmap/","neighbours":{"roadmap":[{"id":"linac-machines-roadmap","kind":"roadmap","name":"Linear accelerator machines: from Clinac to AI-imaging linacs, rings and radiosurgery units","route":"/roadmaps/linac-machines-roadmap/"},{"id":"radiation-roadmap","kind":"roadmap","name":"Radiotherapy roadmap: X-rays → shaped beams → fewer fractions, particles and FLASH","route":"/roadmaps/radiation-roadmap/"}],"idea":[{"id":"idea-fund-adaptive-radiotherapy-evidence","kind":"idea","name":"Coverage-with-evidence registries for MR-guided and adaptive radiotherapy","route":"/ideas/idea-fund-adaptive-radiotherapy-evidence/"}],"section":[{"id":"devices","kind":"section","name":"Devices & Physical Therapies","route":"/fronts/devices/"},{"id":"radiation","kind":"section","name":"Radiation Therapy","route":"/fronts/radiation/"}],"technology":[{"id":"adaptive-radiotherapy","kind":"technology","name":"Adaptive radiotherapy (online replanning)","route":"/technologies/adaptive-radiotherapy/"},{"id":"biology-guided-radiotherapy","kind":"technology","name":"Biology-guided radiotherapy (RefleXion X1, SCINTIX)","route":"/technologies/biology-guided-radiotherapy/"},{"id":"cobalt-60-teletherapy","kind":"technology","name":"Cobalt-60 teletherapy","route":"/technologies/cobalt-60-teletherapy/"},{"id":"mr-linac","kind":"technology","name":"MR-guided adaptive radiotherapy","route":"/technologies/mr-linac/"},{"id":"pet-ct","kind":"technology","name":"PET/CT","route":"/technologies/pet-ct/"},{"id":"respiratory-gating-tumour-tracking-systems","kind":"technology","name":"Respiratory gating and tumour tracking systems (RPM, ABC, Calypso, Synchrony)","route":"/technologies/respiratory-gating-tumour-tracking-systems/"}],"company":[{"id":"elekta","kind":"company","name":"Elekta","route":"/companies/elekta/"},{"id":"reflexion","kind":"company","name":"RefleXion Medical","route":"/companies/reflexion/"},{"id":"viewray","kind":"company","name":"ViewRay (MRIdian)","route":"/companies/viewray/"}],"bottleneck":[{"id":"b-surgery-radiation-innovation","kind":"bottleneck","name":"Surgery and radiotherapy cure most, get least","route":"/bottlenecks/b-surgery-radiation-innovation/"}]}}