Entrants, exits, funding, launches, recalls — ctdna mrd assay validation

1. Summary

The one event with the widest reach across every player in this domain is regulatory, not commercial: FDA's May 2024 final rule would have brought laboratory-developed tests — including every tumor-informed ctDNA MRD assay this dossier tracks — under device regulation for the first time, and a federal court vacated that rule in March 2025, which FDA's own September 2025 implementation notice confirms reverted the definition of "in vitro diagnostic products" to its pre-2024 text [1][2]. Consistent with that reversal, a fresh scan of FDA's 510(k)/clearance and recall registries returns zero records for any tumor-informed ctDNA MRD assay or for any of the three reference-material vendors and assay manufacturers named in this domain's dossier [3][4]. Where visible growth is actually happening is ClinicalTrials.gov: Natera and Guardant Health have each registered new sponsor-led trials extending their assays into indications beyond colorectal cancer, Exact Sciences has registered a large observational study extending Oncodetect into breast cancer, and at least one third-party drug developer has built a Phase 3 trial's own enrollment criteria around a named incumbent assay [5][6][7][8][10]. Real corporate-transaction activity (acquisitions, a bankruptcy sale, a nine-figure jury verdict, a patent-invalidity ruling) was located this pass and is named specifically in section 5, but is not carried forward as a numbered finding here — see the scope note above.

2. What Changed

_Baseline (v1). No prior version; this establishes the starting point for future diffs._

3. Details

The regulatory event that would have made every one of these assays a "device" — and its reversal

FDA's final rule "Medical Devices; Laboratory Developed Tests" (89 FR 37286, published 2024-05-06, effective 2024-07-05) amended the regulatory definition of "in vitro diagnostic products" at 21 CFR 809.3 to explicitly include laboratory-developed tests, the first step of a phase-out plan intended to bring LDTs — the regulatory category every tumor-informed ctDNA MRD assay in this domain currently sits in — under the same premarket-review framework as a manufactured device [1]. A federal district court vacated that rule; FDA's own follow-on rule, "Regulation Identification Number 0910-AJ05 Medical Devices; Laboratory Developed Tests; Implementation of Vacatur" (90 FR 45134, published 2025-09-19, effective the same day), states that a federal district court vacated the 2024 rule on March 31, 2025, and that the new rule "reverts to the text of the regulation as it existed prior to the effective date of the May 2024 final rule" [2]. Read together, these two documents describe the one regulatory event in this window that would have converted every incumbent and entrant in this domain into an FDA-regulated device maker, and its full reversal roughly a year later.

No cleared or approved tumor-informed ctDNA MRD device exists in the registries checked

Re-running the openFDA 510(k)/clearance scan for this report (device_name="circulating tumor DNA" and device_name="minimal residual disease," five-year window) returns zero records, and a named-applicant search against Natera and Guardant Health individually returns no 510(k) record either [3]. This is the registry-level confirmation of what the vacatur in [2] leaves in place: under the current text of 21 CFR 809.3, a tumor-informed ctDNA MRD assay marketed as a laboratory-developed test does not require the 510(k) or PMA filing this scan would have found.

No device recall recorded for any named assay maker or reference-material vendor

A firm-by-firm openFDA device-recall scan (ten-year window) for Natera, Guardant Health, LGC, Revvity, Twist Bioscience, Personalis, Labcorp, Quest Diagnostics and SeraCare — the assay manufacturers and reference-material vendors this domain's dossier names — returns zero recall records for every one of them [4]. Device-recall reporting obligations sit at 21 CFR 806.10, a regulation that governs manufactured devices; its silence here is consistent with, not independent confirmation of, the LDT status established above — an RUO reagent or an LDT is not the kind of product this specific database is built to capture in the first place.

Where the entrant and expansion activity actually is: sponsor-registered trials, not FDA filings

Both of the two largest incumbents are visibly extending their assays into new tumor types through newly registered trials rather than through any device filing. Natera registered NCT07565857, "Signatera-Guided De-escalation of Adjuvant Therapy in Resectable Stage II-IVa Gastric/Gastric-Esophageal Cancer" (not yet recruiting as of this report's run date), and NCT07339384, "Signatera Assessment in Early-Stage Endometrial Cancer" (also not yet recruiting) — both first posted in 2025-2026, both outside the colorectal-cancer indication this domain's dossier treats as Signatera's established base [sponsor-reported][5][6]. Guardant Health sponsors NCT05059444 ("ORACLE: Observation of ResiduAl Cancer With Liquid Biopsy Evaluation"), an observational study of Guardant Reveal, status RECRUITING [sponsor-reported][7]. Exact Sciences sponsors NCT06401421 ("EXActDNA-003 / NSABP B-64"), a RECRUITING observational study extending its Oncodetect assay into high-risk early breast cancer with an ESTIMATED — sponsor target, not an achieved — enrollment of 1,800 [sponsor-reported][8]. A distinct signal of adoption beyond the assay-maker's own trial program: NCT07021989, an investigator-sponsored (not company-sponsored) Phase 2 trial for relapsed/refractory Hodgkin lymphoma, names Foresight CLARITY as its ctDNA-guidance intervention, status RECRUITING [sponsor-reported][9] — an academic sponsor building a trial around a named commercial assay is a different kind of market signal than the assay-maker's own registrations above. Separately, a third-party drug developer has written a named incumbent's assay directly into a pivotal trial's eligibility criteria: Exelixis's NCT07750158, a randomized Phase 3 colorectal-cancer trial (ESTIMATED enrollment 600, status NOT_YET_RECRUITING), requires that enrolled patients be "ctDNA-positive based on local testing using the Natera Signatera tissue-informed molecular residual disease (MRD) assay" as a named inclusion criterion, and tracks "Proportion of Participants with ctDNA Clearance" as a secondary endpoint [sponsor-reported][10] — commercial traction expressed as a biopharma sponsor's own enrollment-criterion choice, not a claim about what any clinician would prefer.

4. Sources

[1] Medical Devices; Laboratory Developed Tests — Federal Register, Food and Drug Administration (published 2024-05-06; accessed 2026-09-01). 89 FR 37286, FR Doc. 2024-08935 — https://www.federalregister.gov/documents/2024/05/06/2024-08935/medical-devices-laboratory-developed-tests [federal-registry] [2] Regulation Identification Number 0910-AJ05 Medical Devices; Laboratory Developed Tests; Implementation of Vacatur — Federal Register, Food and Drug Administration (published 2025-09-19; accessed 2026-09-01). 90 FR 45134, FR Doc. 2025-18239 — https://www.federalregister.gov/documents/2025/09/19/2025-18239/regulation-identification-number-0910-aj05-medical-devices-laboratory-developed-tests-implementation [federal-registry] [3] openFDA device/510k scan, device_name="circulating tumor DNA" and device_name="minimal residual disease" (five-year window ending 2026-09-01), plus applicant-name searches for Natera and Guardant — FDA (queried 2026-09-01; accessed 2026-09-01). Zero records matched in every query; cf. definition of "in vitro diagnostic products" at 21 CFR 809.3 — https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm [federal-registry] [4] openFDA device/recall scan, recalling_firm=Natera/Guardant/LGC/Revvity/Twist Bioscience/Personalis/Labcorp/Quest Diagnostics/SeraCare, ten-year window ending 2026-09-01 — FDA (queried 2026-09-01; accessed 2026-09-01). Zero records matched for every firm; cf. device-recall reporting duty at 21 CFR 806.10 — https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfRES/res.cfm [federal-registry] [5] ClinicalTrials.gov NCT07565857 — "Signatera-Guided De-escalation of Adjuvant Therapy in Resectable Stage II-IVa Gastric/Gastric-Esophageal Cancer," sponsor Natera, Inc. (record first posted 2026, day/month not given in the connector record; accessed 2026-09-01). Status NOT_YET_RECRUITING, hasResults=false. NCT07565857 — https://clinicaltrials.gov/study/NCT07565857 [trial-registry] [6] ClinicalTrials.gov NCT07339384 — "Signatera Assessment in Early-Stage Endometrial Cancer," sponsor Natera, Inc. (record last updated 2026-01-14; accessed 2026-09-01). Status NOT_YET_RECRUITING, hasResults=false. NCT07339384 — https://clinicaltrials.gov/study/NCT07339384 [trial-registry] [7] ClinicalTrials.gov NCT05059444 — "ORACLE: Observation of ResiduAl Cancer With Liquid Biopsy Evaluation," sponsor Guardant Health, Inc. (record last updated 2025-08-22; accessed 2026-09-01). Status RECRUITING, hasResults=false, observational. NCT05059444 — https://clinicaltrials.gov/study/NCT05059444 [trial-registry] [8] ClinicalTrials.gov NCT06401421 — "EXActDNA-003 / NSABP B-64: Study of Molecular Residual Disease Detection in Breast Cancer (MRD)," sponsor Exact Sciences Corporation (record last updated 2026-01-20; accessed 2026-09-01). Status RECRUITING, hasResults=false, observational, enrollment 1800 (ESTIMATED). NCT06401421 — https://clinicaltrials.gov/study/NCT06401421 [trial-registry] [9] ClinicalTrials.gov NCT07021989 — "ctDNA-Guided Therapy for Relapsed/Refractory Hodgkin Lymphoma," sponsor Michael Spinner, MD (investigator-sponsored, not the assay manufacturer; record last updated 2026-08-20; accessed 2026-09-01). Status RECRUITING, hasResults=false, phase 2, intervention includes Foresight CLARITY. NCT07021989 — https://clinicaltrials.gov/study/NCT07021989 [trial-registry] [10] ClinicalTrials.gov NCT07750158 — "Zanzalintinib Alone or in Combination With Pembrolizumab and Berahyaluronidase Alfa in Participants With Colorectal Cancer With Molecular Residual Disease," sponsor Exelixis (record last updated 2026-08-25; accessed 2026-09-01). Status NOT_YET_RECRUITING, hasResults=false, phase 3, randomized, enrollment 600 (ESTIMATED); eligibility requires local testing "using the Natera Signatera tissue-informed molecular residual disease (MRD) assay." NCT07750158 — https://clinicaltrials.gov/study/NCT07750158 [trial-registry]

5. Sourcing & Gaps

Well established: the vacatur sequence [1][2] rests on FDA's own two Federal Register filings, which are each authoritative about their own content; nothing in this report rests on two independent, non-affiliated organizations agreeing on the same fact, and that is disclosed rather than smoothed over — a federal register document, a registry scan and a trial record are each exactly one source, however authoritative.

Thin: every trial-registry line in section 3 [5][6][7][8][9][10] carries [sponsor-reported] because none has posted results, and the enrollment figures quoted for [8] and [10] are ESTIMATED targets the sponsor registered, not counts of anyone actually enrolled. The registry absence findings [3][4] are each a single connector query's result, not independently cross-checked against a second federal database.

Rescoped from class 3: none in this report. Every line here is either a registry fact (evidence class 1: what a federal filing or a trial registration says) or, for the sponsor- registered trials, the closest revealed-behaviour evidence available for "is anyone actually expanding this assay's use" — a sponsor's own registration of a real, resourced trial, as opposed to a stakeholder's stated intention to do so.

Out of scope: substantial, on-topic market-player activity was located this pass via WebSearch and WebFetch of primary company and court documents but is not carried forward as a numbered finding, because none of the underlying documents carries a resolvable identifier in this fleet's closed vocabulary (a company press release and an SEC filing accession number are each only a URL by this checker's own definition; a federal court docket number, e.g. 3:21-cv-04062 or 1:23-cv-00629, does not match any pattern in that vocabulary either). Named specifically, so a later reader can see the shape of the hole: Quest Diagnostics' 2023 acquisition of Haystack Oncology (Quest's own 10-Q states approximately $300 million cash at closing plus up to $150 million in contingent milestones); Labcorp's 2024 acquisition of select Invitae assets for $239 million out of Invitae's Chapter 11 bankruptcy (Invitae's own SEC Form 8-K, filed 2024-08-07, states the $239,000,000 cash purchase price and the May 1, 2024 asset purchase agreement with Labcorp); Natera's December 2025 all-stock acquisition of Foresight Diagnostics (Natera's own SEC Form 8-K, filed 2025-12-05, states the consideration in shares of common stock; Natera's press release states $275 million upfront plus up to $175 million in milestones); the November 2024 jury verdict of $292.5 million against Natera in Guardant Health, Inc. v. Natera, Inc. (N.D. Cal.) for false advertising concerning Signatera versus Reveal; and the August 2025 summary-judgment ruling invalidating Natera's asserted patents in Natera, Inc. v. NeoGenomics Laboratories, Inc. (M.D.N.C.), clearing NeoGenomics to commercialize its RaDaR ST assay. Each of these was read from a primary company statement or a directly fetched SEC filing, not from a secondary news summary alone, but is excluded here strictly on the identifier rule stated above.

Not searched vs. not found: a PubMed search for "FDA laboratory developed test rule liquid biopsy oncology regulation" (three-year window) returned zero records — confirmed not found, not merely not searched. A systematic enumeration of every sponsor-registered trial using each of the domain's named assays as an eligibility or intervention term was not searched to completeness in this pass; the ClinicalTrials.gov connector's own truncation notices show more matching records exist for "Signatera" (17 total, 10 shown) and "RaDaR" (56 total, mostly off-topic homonyms) than were reviewed here. Whether any company named in this report has filed a Q-Submission or Breakthrough Device Designation request with FDA — a step short of a 510(k)/PMA that would not appear in the clearance database searched — was not searched, no connector in this repo reaches that FDA correspondence.

[inference] None in this report; section 3 is registry description, not synthesis.

6. Claim Candidates