# RAINBO

Source: https://onco.cc/trials/rainbo/  
OnCo record `rainbo` (Trial). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

RAINBO is a programme of four trials that tailors treatment after surgery for womb cancer to the tumour's molecular type; in its POLEmut-BLUE arm, women whose tumours carry a POLE mutation and almost never relapse have chemotherapy withheld and receive radiotherapy alone or no further treatment, and the results are awaited.

## Summary

RAINBO (Refining Adjuvant treatment IN endometrial cancer Based On molecular features) is an international programme registered by Leiden University Medical Center with ENGOT, the Canadian Cancer Trials Group and University College London as trial sponsors, planned for 1,615 patients. It assigns endometrial cancer after surgery to one of four trials by molecular class: p53abn-RED randomises chemoradiotherapy with or without olaparib; MMRd-GREEN randomises pelvic radiotherapy with or without durvalumab against chemoradiotherapy; NSMP-ORANGE tests progestin with radiotherapy against chemoradiotherapy; and POLEmut-BLUE, a single-arm de-escalation study, gives radiotherapy alone or observation to stage I to II and selected stage III POLE-mutated tumours. Each trial's primary endpoint is measured at three years.

The registry lists the programme as recruiting with completion in 2031 and no results. The corpus's POLE-ultramutated endometrial cancer page cites RAINBO POLEmut-BLUE for pelvic radiotherapy without chemotherapy.

## Fields

- Kind: Trial
- Status: recruiting
- Last checked: 2026-09-22
- Also known as: RAINBO programme; POLEmut-BLUE; p53abn-RED; MMRd-GREEN; NSMP-ORANGE
- Tags: soc-trials
- Registry id: NCT05255653
- Phase: 2/3
- Setting: Endometrial cancer stratified by molecular class after surgery: four linked trials that test olaparib with chemoradiotherapy for p53-abnormal tumours (p53abn-RED), durvalumab with radiotherapy for mismatch-repair-deficient tumours (MMRd-GREEN), progestin with radiotherapy for tumours with no specific molecular profile (NSMP-ORANGE), and de-escalation to radiotherapy alone or observation for POLE-ultramutated tumours (POLEmut-BLUE)
- Sponsor: Leiden University Medical Center (RAINBO Research Consortium)
- Enrolled: 1615

## Sources

- ClinicalTrials.gov NCT05255653: https://clinicaltrials.gov/study/NCT05255653

## Connected records

- cancers: [Mismatch-repair-deficient endometrial cancer](https://onco.cc/cancers/endometrial-mmr-deficient/), [POLE-ultramutated endometrial cancer](https://onco.cc/cancers/endometrial-pole-ultramutated/)
- technologies: [IMRT / IGRT (modern external beam)](https://onco.cc/technologies/imrt-igrt/)
- drugs: [Durvalumab](https://onco.cc/drugs/durvalumab/), [Megestrol acetate](https://onco.cc/drugs/megestrol/), [Olaparib](https://onco.cc/drugs/olaparib/)
- institutions: [Leiden University Medical Center](https://onco.cc/institutions/lumc-leiden/)

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JSON: https://onco.cc/api/v1/entities/rainbo.json