Scientific Article | Published June 1, 2026 | Author: Sarah McKeown, PhD

Integrating Proteomics into Oncology Phase I/II Clinical Trials

Integrating global mass-spectrometry based proteomics into early Phase I/II clinical trials allows oncology drug developers to establish quantitative target engagement, map kinome bypass networks, and define predictive patient selection biomarkers, addressing the 95% clinical failure rate seen in oncology pipelines.

Introduction: The Efficacy Barrier in Oncology

According to comprehensive clinical trial success analyses, cancer therapeutics experience the highest attrition rate of any major therapeutic class. Specifically, oncology compounds face a 95% failure rate when transition from preclinical models into active clinical trials, achieving a mere 3.4% regulatory approval probability (Wong, Siah & Lo, 2019).

Clinical trial data audits reveal that over 90% of these failures are directly driven by a lack of clinical efficacy (40-50%) or safety and toxicity concerns (30%) (Sun et al., 2022). These statistics highlight a clear gap: traditional preclinical DNA-seq and RNA-seq profiling fail to reflect the dynamic signaling activity that determines clinical drug response.

Establishing Target Engagement and Mechanism of Action

In early Phase I trials, establishing that a compound successfully binds to and modulates its molecular target is critical. While transcriptomic profiling monitors downstream genomic transcription, it does not measure active protein-level signaling.

By incorporating global phosphoproteomics into Phase I trial designs (using pre- and post-treatment biopsies), researchers can directly map active kinase signaling networks. For kinase inhibitors, this allows direct monitoring of the phosphorylation status of target residues and downstream substrate proteins, proving target engagement at the molecular level.

Predicting Bypass Resistance Cascades

Oncology therapeutic candidates commonly face rapid resistance emergence, as cancer cells reactivate signaling networks through alternative pathway loops (bypass resistance).

Integrating global proteomics during Phase II trials helps identify these feedback loops early. For instance, when treating high-grade serous ovarian cancer cells with PARP inhibitors, unbiased mass spectrometry monitors whether compensation networks (such as RTK/PI3K pathway activation) are up-regulated. This systems-level data provides a rational basis for designing combination trial arms before registrational phases begin.

Companion Diagnostic Translation

Once a predictive proteomic signature is isolated in early clinical phases, it must be translated into a clinical test to qualify trial cohorts. Following Yatiri Bio's acquisition of NGeneBioAI in 2025, we validate these signatures into certified assays inside our CLIA/CAP laboratory facilities in San Diego.

Transitioning from research global scans to targeted assays (such as PRM mass spectrometry or ELISA) inside a certified lab provides the regulatory compliance needed to support companion diagnostic applications, de-risking Phase II/III trial runs.