IVDR Compliance for NGS Assays: 7 Challenges and How to Solve Them

Marketa Svobodova

TL;DR | What You Need to Know

NGS-based IVDs face unique IVDR compliance challenges, from validating bioinformatics pipelines under IEC 62304 to demonstrating scientific validity across thousands of genes. Most NGS assays classify as IVDR Class C or D, requiring Notified Body review, comprehensive performance evaluation, and lifecycle documentation. This article covers the 7 critical challenges and practical solutions, informed by MDx’s experience CE-marking one of the world’s first 4,600+ gene panels under IVDR.

Next-Generation Sequencing (NGS) has revolutionized molecular diagnostics by enabling simultaneous analysis of hundreds or thousands of genes across diverse clinical applications. These include germline testing for hereditary disorders, somatic mutation profiling in oncology, infectious disease characterization, and transcriptomic gene expression analysis.

A particularly impactful advancement is liquid-biopsy NGS, which allows non-invasive detection of tumor-derived nucleic acids, such as circulating tumor DNA (ctDNA) or RNA, from blood or other bodily fluids. This method now supports cancer screening, minimal residual disease monitoring, and therapy stratification.

NGS also powers Comprehensive Genomic Profiling (CGP). These assays assess a wide spectrum of biomarkers, single nucleotide variants (SNVs), insertions and deletions (indels), copy number alterations (CNAs), copy number losses (CNLs), gene fusions, and splicing events, across large panels in a single run. Many workflows also integrate microsatellite instability (MSI) and tumor mutational burden (TMB).

Assays can range from targeted panels to whole exome sequencing (WES) or whole genome sequencing (WGS). Each format carries unique validation needs and bioinformatics requirements. The mix of technologies, analytes, sample types (e.g., blood, plasma, FFPE, cfDNA, RNA), and clinical contexts increases regulatory complexity.

Under the EU In Vitro Diagnostic Regulation (IVDR; EU 2017/746), you must define each intended use clearly and support it with comprehensive evidence of scientific validity, analytical performance, and clinical performance. That requirement calls for a holistic, coordinated validation and documentation strategy.

For CE-marking manufacturers and clinical laboratories operating under Article 5(5), IVDR demands structured validation, clear documentation, and lifecycle management. For NGS-based assays, compliance becomes even more demanding due to scientific, technical, and operational intricacies.

Key Challenges in IVDR Compliance for NGS

1) Complex Gene Panels & Variant Diversity

NGS panels often include multiple genes and variant types, each with distinct performance characteristics. You must demonstrate analytical performance—sensitivity, specificity, LoD, and robustness—per variant class. This tailoring increases the scale and complexity of testing.

2) Defining a Clear Intended Use

A precise, testable intended purpose statement anchors the program. Define analytes, clinical context, sample types, output format, and role in patient care. Any ambiguity risks misclassification or validation gaps.

3) Scientific Validity Across Many Analytes and Conditions

Establishing scientific validity grows challenging when one test targets dozens or hundreds of genes. Under IVDR, link each analyte to a clinically relevant condition. That linkage often requires extensive literature review, database referencing, and written justification for inclusion.

4) Clinical Performance Evidence

With broad genomic scope, comprehensive clinical studies may be infeasible. A pragmatic approach combines routine diagnostic data, published literature, and a clear link to Post-Market Performance Follow-up (PMPF) plans to support claims over time.

5) Complex Bioinformatics Pipelines

Bioinformatics sits at the core of NGS diagnostics. Validate every step—from base calling to variant annotation. Implement version control, clear revalidation triggers, and change management to maintain consistent performance after software updates.

6) Use of Third-Party Reagents and Instruments

NGS workflows often incorporate off-the-shelf reagents and platforms not originally CE-marked as part of the IVD system. Document compatibility, performance, and traceability of third-party components to meet IVDR expectations.

7) Labelling Without a Physical Device

Many NGS assays function as software-driven services or LDTs without a packaged device. You still must meet Annex I labelling and Instructions for Use (IFU) requirements—even without physical labels or packaging.

How MDx CRO Supports Your IVDR Journey

MDx CRO brings specialized expertise to guide NGS programs through IVDR across the full lifecycle:

Gap Assessments: Identify regulatory shortfalls and prioritize remediation.
Performance Evaluation Plan (PEP): Craft PEPs that balance analytical rigor with operational feasibility.
Analytical Study Oversight: Design statistically robust studies tailored to complex panels.
Bioinformatics Validation: Map and validate each software component under IEC 62304 and ISO 13485.
QMS Integration: Build audit-ready documentation, risk management, and traceability.
PMS & PMPF Strategies: Establish real-world evidence systems that sustain compliance and support clinical claims.

Frequently Asked Questions

What IVDR class are NGS-based diagnostic tests?

Most NGS-based diagnostic tests fall into IVDR Class C because they typically provide high-risk individual patient information (e.g., germline disease or somatic mutation profiling). NGS assays used for infectious disease with high public health risk may classify as Class D. Classification depends on the specific intended use, clinical claims, and risk profile of each test.

How do you validate an NGS bioinformatics pipeline for IVDR compliance?

Under IVDR, bioinformatics pipelines must be validated as medical device software following IEC 62304 and IEC 82304-1. This includes documenting the software architecture, implementing version control and change management, verifying variant calling accuracy at each step (base calling, alignment, variant annotation), and establishing revalidation triggers for software updates. Risk management per ISO 14971 must also be integrated into the software lifecycle.

How do you demonstrate scientific validity for a large NGS gene panel under IVDR?

For large panels covering hundreds or thousands of genes, a tiered evidence strategy is recommended. This combines validation of exome sequencing as a methodology, reliance on curated public databases (e.g., ClinVar, OMIM) for gene-disease associations, and deep exemplar evidence for high-prevalence genes. Low-prevalence genes are supported through a structured Post-Market Performance Follow-up (PMPF) plan that matures evidence over time.

Do clinical laboratories running NGS LDTs need to comply with IVDR?

Yes. Under IVDR Article 5(5), EU health institutions manufacturing and using in-house IVDs (including NGS-based laboratory-developed tests) must meet six specific conditions: justification that no equivalent CE-marked device meets patient needs, ISO 15189-compliant QMS, alignment with IVDR General Safety and Performance Requirements, documentation of design and manufacture, and publication of a public declaration. Laboratories that cannot meet these conditions must pursue CE marking.

What are the biggest challenges in achieving IVDR compliance for NGS assays?

The seven key challenges are: (1) demonstrating analytical performance across complex gene panels and diverse variant types, (2) defining a precise intended use statement, (3) establishing scientific validity across many analytes, (4) generating clinical performance evidence at scale, (5) validating bioinformatics pipelines as medical device software, (6) documenting third-party reagents and instruments not originally CE-marked, and (7) meeting IVDR labelling requirements for software-based or service-based assays without a physical device.”

Conclusion

Achieving IVDR compliance for NGS assays poses a multi-dimensional challenge that blends regulatory discipline with scientific depth. From defining intended use to managing software changes and clinical claims, every step benefits from clarity, structure, and foresight.

MDx CRO partners with diagnostics developers and clinical laboratories to turn regulatory complexity into actionable validation strategies, accelerating time to market while protecting long-term compliance and patient safety.