TL;DR: Liquid Biopsy Investment Due Diligence
- Separate MCED screening, MRD, monitoring, and therapy-selection claims (Wan et al., 2017)
- CCGA validation and PATHFINDER feasibility answer different questions (Klein et al., 2021; Schrag et al., 2023)
- MRD evidence is advancing in CRC with prospective and randomized data (Kotani et al., 2023; Tie et al., 2022)
- Pre-analytical variables and clonal hematopoiesis affect false positives (Alix-Panabières & Pantel, 2021; Razavi et al., 2019)
- Motif maps liquid-biopsy literature with PMIDs for investor and founder diligence
From the Motif team: Liquid biopsy decks often mix MCED, MRD, and therapy-selection claims. We separate those indications in literature exports with PMIDs from PubMed, PMC, and Europe PMC. We do not provide investment advice.
Liquid biopsy companies promise non-invasive cancer detection and monitoring. Investment diligence should map each claim to published studies: screening in asymptomatic adults, MRD after surgery, serial monitoring on therapy, or mutation detection for targeted treatment (Wan et al., 2017).1 Slides that blend indications without PMIDs are a red flag.
MCED Screening: Development vs Prospective Feasibility
Klein et al. (2021) reported clinical validation of a methylation-based MCED test in an independent validation set following CCGA development work.2 Case-control development sensitivity does not equal population screening performance; stage mix, prevalence, and workup harm must be modeled separately.
Schrag et al. (2023) reported PATHFINDER as a prospective feasibility study: cancer signal detected in 1.4% of asymptomatic participants, with cancer confirmed in 0.5% after diagnostic workup.3 Feasibility demonstrates workflow operability; mortality benefit requires randomized screening trials with defined follow-up.
MRD and Treatment-Decision Evidence
Kotani et al. (2023) analyzed postsurgical ctDNA in resectable colorectal cancer in the GALAXY arm of CIRCULATE-Japan. Postsurgical ctDNA positivity at four weeks associated with higher recurrence risk (HR 10.0) and identified patients who appeared to benefit from adjuvant chemotherapy.4 MRD is moving from prognostic research toward randomized management trials.
Tie et al. (2022) randomized stage II colon cancer to ctDNA-guided versus standard adjuvant chemotherapy decisions. ctDNA-guided management reduced chemotherapy use (15% vs 28%) while meeting prespecified non-inferiority for recurrence-free survival.5 Five-year follow-up reported similar recurrence-free and overall survival between arms.6
MRD platforms should be diligenced on assay design (tumor-informed vs tumor-naive), turnaround time, clearance dynamics on therapy, and which PMIDs support each intended use.
Monitoring and Therapy Selection
Dawson et al. (2013) demonstrated ctDNA tracking in metastatic breast cancer with changes preceding imaging in some patients.7 Monitoring investments should cite monitoring-specific publications, not screening cohorts.
Razavi et al. (2019) showed mixed tumor and non-tumor contributions to plasma variants, relevant to false-positive rates and clonal hematopoiesis.8 Diligence memos should address CHIP filtering and variant source attribution.
Technology and Operational Diligence
Alix-Panabières and Pantel (2021) note that pre-analytical handling strongly affects liquid biopsy performance. DOI: 10.1038/s41571-021-00486-5. Companies that omit collection and processing detail in publications are harder to benchmark across sites.
Build a competitive matrix with columns for indication, specimen type, analyte, pivotal PMID, study design, and regulatory status. Do not pool incompatible assays into one sensitivity number.
Investment Red Flags in Liquid Biopsy Decks
- Single sensitivity number pooled across MCED, MRD, and mutation-detection assays
- Case-control development stats presented as population screening performance
- No plan for CHIP filtering or variant source attribution (Razavi et al., 2019)
- PATHFINDER feasibility cited as mortality benefit without pivotal screening trial design
- MRD claims without specifying tumor-informed versus tumor-naive assay architecture
Literature Workflow in Motif
- Scope by indication: MCED, MRD, resistance monitoring, or companion diagnostic mutation
- Extract sensitivity, specificity, PPV, stage breakdown, and PMIDs per study
- Compare assay platforms and LOD claims across papers
- Export cited tables for IC memos and scientific advisory review
Read our blog on liquid biopsy biomarkers to learn more about clinical contexts. For precision-medicine framing, read our blog on personalized medicine biomarker analysis to learn more.
References
- Wan, J.C.M., et al. (2017). Liquid biopsies come of age. Nat Rev Cancer, 17(4), 223-238. PMID: 28233803
- Klein, E.A., et al. (2021). MCED clinical validation. Ann Oncol, 32(9), 1167-1177. PMID: 34176681
- Schrag, D., et al. (2023). PATHFINDER MCED feasibility. Lancet, 402(10409), 1251-1260. PMID: 37805216
- Kotani, D., et al. (2023). MRD and adjuvant chemotherapy in CRC. Nat Med, 29(1), 127-134. PMID: 36646802
- Tie, J., et al. (2022). ctDNA-guided adjuvant therapy in stage II colon cancer. NEJM, 386(24), 2261-2272. PMID: 35657320
- Tie, J., et al. (2025). DYNAMIC trial 5-year outcomes. Nat Med. PMID: 40055522
- Dawson, S.J., et al. (2013). ctDNA monitoring in metastatic breast cancer. NEJM, 368(13), 1199-1209. PMID: 23484797
- Razavi, P., et al. (2019). Sources of plasma cfDNA variants. Nat Med, 25(12), 1928-1937. PMID: 31792460
- Alix-Panabières, C., & Pantel, K. (2021). Liquid biopsy clinical application. Nat Rev Cancer, 21(6), 374-388. DOI: 10.1038/s41571-021-00486-5
