As Antibody-Drug Conjugates (ADCs) reshape the therapeutic landscape, commercial success depends on visibility into novel protein expression biomarkers.
For the last decade, the narrative of precision oncology has been largely written in the language of genomics. Biomarkers based on DNA mutations—like ALK, ROS1, and BRAF V600E—have been the primary drivers of targeted therapy.
But the narrative is changing. The rapid rise and commercial success of Antibody-Drug Conjugates (ADCs) have shifted the spotlight from gene-level mutations back to protein expression measured by Immunohistochemistry (IHC).
While generic IHC markers like PD-L1 are well-established, a new wave of high-value, novel protein targets is redefining standards of care in solid tumors. For commercial teams, the challenge is no longer just tracking testing rates; it’s gaining early visibility into specific, emerging targets before they become commoditized.
Here is a look at the three targets currently dominating the diagnostic conversation and why tracking their real-world adoption is critical:
1. FOLR1 (Folate Receptor Alpha)
In ovarian cancer, FOLR1 has rapidly emerged as a critical biomarker. Following recent FDA approvals for ADCs targeting this protein, FOLR1 testing is fast becoming a standard step in patient identification. The commercial success of initial therapies in this space has triggered a development race, with multiple competing assets currently in Phase 3 trials. Understanding the velocity of FOLR1 test ordering is now essential for modeling the ovarian cancer market.
2. CLDN18.2 (Claudin 18.2)
The gastric and gastroesophageal junction (GEJ) cancer landscapes are undergoing a significant shift due to CLDN18.2. With recent approvals of targeted therapies, CLDN18.2 testing has now entered NCCN recommendations and is expected to become standard-of-care testing. We are witnessing the transition of a niche biomarker into a frontline diagnostic requirement.
3. cMET Overexpression
The MET pathway is complex. While several successful therapies already target MET exon 14 skipping mutations, the next generation of ADCs is focused on a broader target: cMET protein overexpression. Distinguishing between mutation-based testing and protein expression-based testing is vital in NSCLC. With new cMET-targeting ADCs entering the market and expecting rapid adoption, differentiating these diagnostic workflows is key to understanding market potential.
The "Parallel Diagnostic" Reality
The rise of these protein targets does not mean the end of genomic testing. In complex tumor types, specialists are increasingly adopting a "parallel diagnostic" strategy. They aren't choosing between Next-Generation Sequencing (such as liquid biopsy) and IHC; they are ordering concurrent tissue testing for protein targets alongside genomic panels to capture the complete patient profile.
Gaining Visibility into Novel Markers
Data on established markers is easy to find. Data on novel IHC targets—specifically seeing where they overlap with NGS ordering—is scarce.
To model launch trajectories accurately, commercial teams need access to diagnostic data that reflects this new reality. Through exclusive partnerships with the nation's leading diagnostic hubs, we are gaining unprecedented, early access to ordering data for FOLR1, CLDN18.2, and cMET alongside concurrent liquid biopsy orders.
Don't wait for these markers to become generic. Contact us today to learn how to access real-world data on these high-value IHC targets - prognoshealth.com/learn-more.