# MiRaDoR

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

## TL;DR

A Spanish-led study that watches the blood of women with hormone-receptor-positive breast cancer and, if tumour DNA appears, tests newer hormone drugs to try to clear it.

## Summary

MiRaDoR (NCT05708235, MedSIR) enrols 976 patients into ctDNA surveillance with a tumour-informed panel built from tumour and matched normal sequencing; only patients confirmed ctDNA-positive by the Signatera Genome test enter the treatment phase, where they receive giredestrant, giredestrant with abemaciclib, or, if their tumour carries a PIK3CA mutation on tissue, giredestrant with inavolisib. The primary endpoint is a decrease or clearance of ctDNA three months after starting treatment. The PIK3CA gate is read from the original tumour, not from what remains in the blood.

## Fields

- Kind: Trial
- Status: active
- Last checked: 2026-11-04
- Also known as: MIRADOR; MedOPP485
- Registry id: NCT05708235
- Phase: 2
- Setting: HR-positive, HER2-negative early breast cancer at higher risk, operated on within five years: ctDNA surveillance, then treatment arms for patients who become ctDNA-positive (continued endocrine therapy, giredestrant, giredestrant plus abemaciclib, or giredestrant plus inavolisib for PIK3CA-mutated tumours)
- Sponsor: MedSIR
- Enrolled: 976

## Sources

- ClinicalTrials.gov NCT05708235: https://clinicaltrials.gov/study/NCT05708235

## Connected records

- cancers: [HR-positive / HER2-negative breast cancer](https://onco.cc/cancers/breast-hr-positive/)
- technologies: [MRD / molecular residual disease testing](https://onco.cc/technologies/mrd-testing/)
- targets: [Estrogen receptor (ERα)](https://onco.cc/targets/estrogen-receptor/), [PIK3CA / PI3K-alpha](https://onco.cc/targets/pik3ca/)
- drugs: [Abemaciclib](https://onco.cc/drugs/abemaciclib/), [Giredestrant](https://onco.cc/drugs/giredestrant/), [Inavolisib](https://onco.cc/drugs/inavolisib/), [Signatera](https://onco.cc/drugs/signatera/)
- terms: [Circulating tumour DNA (ctDNA)](https://onco.cc/terms/ctdna/), [Minimal / molecular residual disease (MRD)](https://onco.cc/terms/mrd/), [Tumour-informed versus tumour-naive ctDNA assays](https://onco.cc/terms/tumour-informed-assay/)

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