Mission Bio’s Tapestri Enables Single-Cell Profiling of Residual Disease, Identifying AML Patients Likely to Benefit From Motixafortide in the Multicenter BLAST Trial

Key Takeaways

• Tapestri identified high CXCR4 on residual AML cells as predictive marker
• Motixafortide reduced relapse risk only in CXCR4‑high patient subgroup
• Standard MRD assays missed CXCR4 signal due to clonal heterogeneity
• Retrospective finding urges prospective biomarker‑stratified trials for AML
• Single‑cell profiling links protein expression to genetic clone identity

Pulse Analysis

Measurable residual disease (MRD) has become a cornerstone for risk stratification in acute myeloid leukemia, yet conventional bulk assays blur the signal of rare leukemic clones within a sea of normal marrow cells. Mission Bio’s Tapestri platform overcomes this limitation by simultaneously capturing DNA mutations and surface protein markers at true single‑cell resolution. This dual‑omic approach enables clinicians to pinpoint residual leukemic cells, assign them to specific clonal lineages, and quantify phenotypic features such as CXCR4 expression that are invisible to standard flow cytometry or PCR‑based methods.

The retrospective BLAST analysis revealed that high CXCR4 expression on residual leukemic cells correlates with a markedly lower relapse rate when patients receive the CXCR4 antagonist Motixafortide, while the same marker predicts poorer outcomes in the placebo arm. This bidirectional effect underscores the functional relevance of the CXCR4‑CXCL12 axis in marrow‑mediated chemoresistance and validates CXCR4 as a predictive biomarker rather than a mere prognostic indicator. Importantly, the statistical interaction survived multivariable Cox modeling, lending credibility to a treatment‑by‑biomarker hypothesis that could reshape AML consolidation strategies.

From a commercial perspective, the ability to stratify patients based on single‑cell MRD opens new revenue streams for both diagnostic vendors and pharmaceutical companies developing targeted agents. Prospective trials that enroll only CXCR4‑high AML patients could demonstrate larger effect sizes, accelerating regulatory approval pathways for Motixafortide and similar CXCR4 inhibitors. Moreover, the Tapestri platform’s versatility positions it for broader adoption across hematology, solid‑tumor, and cell‑therapy pipelines, reinforcing Mission Bio’s role as a critical enabler of precision oncology and personalized medicine initiatives.