The transition from IVDD to IVDR represents the most significant regulatory change for diagnostic devices in Europe in decades. With extended transition periods now in place, clinical study sponsors face both new challenges and opportunities. Understanding the evolving requirements is essential to staying compliant and keeping studies on track.

What Changed and Why It Matters

The European Union's (EU) transition from the In Vitro Diagnostic Directive (IVDD) to the In Vitro Diagnostic Regulation (IVDR) isn't just a regulatory update—it's a complete transformation of how diagnostic devices are evaluated and approved across Europe. The IVDD was based on a fixed list of medical conditions, making it slow to adapt to emerging health threats. It struggled to keep pace with the rise of new, potentially deadly pathogens and the widespread use of self-administered diagnostic tests that followed. The IVDR was introduced to address the evolving challenges. Under IVDD, many diagnostics could self-certify for CE marking without third-party review. IVDR changes that by requiring most IVDs to undergo conformity assessment by a notified body before receiving a CE mark. This shift raises the bar for clinical evidence and directly affects how validation studies are designed and executed.

The IVDR has been applicable in the EU since May 2022, but applying the regime in reality is more complex. Under IVDR, around 80% of IVDs (Classes B, C, and D) now require notified body assessment, up from less than 10% under IVDD. This major shift introduces regulatory hurdles but also opportunities to rethink how clinical validation studies are designed. The IVDR uses a risk-based classification scheme, which assigns diagnostic medical devices to one of four classes (A through D) based on ascending risk to patients if the device malfunctions, using seven rules to assess such risk.

The Extended Timeline: A Regulatory Lifeline

To facilitate a smooth transition from IVDD to IVDR, transition periods were introduced. Originally, the transition periods were supposed to be much shorter. However, recognizing the industry's struggles to adapt to the new requirements, the European Commission has extended these timelines significantly. The transition period has been extended, provided conditions are met, as follows: December 31 2027 for Class D high individual and public health risk IVDs (e.g., HIV or hepatitis tests) December 31, 2028 for Class C high individual and/or moderate public health risk IVDs (e.g., cancer tests) December 31, 2029 for Class B and Class A sterile lower risk IVDs.

This extension wasn't granted lightly. Officials created the new timeline for the IVDR after accepting that the "grave shortage of notified body capacity" was a threat to the continued supply of tests in the EU. For clinical trial sponsors, this means more time to prepare—but also more uncertainty about supplier readiness.

The Notified Body Bottleneck

One of the most significant challenges facing the industry is the limited availability of notified bodies. As of 2025, fewer than 20 Notified Bodies are designated under the IVDR, compared to 22 designated under the old regime. This represents a significant bottleneck, as a smaller number of notified bodies designated to the IVDR must handle the conformity assessment for the vast majority of IVD devices that now require third-party evaluation.

The capacity crunch is alarming. MedTech Europe, a European trade association representing medical technology industries, raised similar concerns, telling EU regulators more capacity is needed quickly, given that it can take up to two years to sign a contract with a notified body, complete the certification work, and deliver the tests. For sponsors planning clinical studies, this timeline needs to be factored into study planning well in advance.

Direct Impact on Clinical Study Sponsors

The IVDR does not just affect medical device manufacturers; it also reshapes how clinical validation studies are conducted across Europe. Any assay used within a trial for medical decision-making, such as patient selection, treatment allocation, or safety monitoring, is considered an IVD and must comply with IVDR requirements.

Sponsors now face several important changes:

• Stricter Performance Evaluation and Assessment: IVDR introduces more rigorous conformity assessments and performance evaluation standards for clinical assays. This means sponsors must plan for more comprehensive validation studies that demonstrate both analytical and clinical performance.
• Robust Documentation and Evidence: Meeting IVDR demands stronger clinical evidence and detailed documentation. This includes expanded clinical validation data and ongoing post-market performance monitoring obligations.
• Quality Management System Compliance: Manufacturers involved in the study must have a compliant Quality Management System (QMS) in place according to Article 10, paragraph 8 of the IVDR. Sponsors should verify QMS status early to avoid delays.

Companion Diagnostics: A Special Case

For sponsors developing companion diagnostics (CDx). Companion diagnostic (CDx) devices are a specific category of IVDs that provide essential information for the safe and effective use of corresponding therapeutic products. CDx devices are categorized as Class C, signifying a moderate to high risk level, necessitating oversight by a Notified Body and mandatory consultation with a medicines authority like the European Medicines Agency (EMA).

This classification means CDx devices face some of the most rigorous requirements under IVDR, including comprehensive performance studies and enhanced clinical evidence requirements. Clinical evidence, including scientific validity, analytical performance, and clinical performance, is required to demonstrate that the CDx device accurately identifies patients suited for a specific therapy. Following ISO 20916 guidelines for clinical performance studies ensures compliance with the IVDR.

How the IVDR is Reshaping Clinical Study Strategy

For clinical trial sponsors working with diagnostics, the transition from IVDD to IVDR is a structural change that affects how trials are planned, approved, and run in the EU. Understanding where the roadblocks and opportunities lie is critical for staying on track and ahead.

Key Risks:

• Timeline Delays: Differing interpretations of the IVDR across IVD manufacturers, drug sponsors, ethics committees, and regulators are causing bottlenecks and slowing down trial approvals.
• Rising Costs: The increased rigor of IVDR compliance comes with higher administrative and operational expenses.
• Supply Chain Strain: Limited capacity among notified bodies may result in delays to device certification, impacting study timelines.

Emerging Opportunities:

• Competitive Edge: Sponsors who adapt early to IVDR requirements can position themselves as reliable partners and enter the market ahead of competitors.
• Improved Data Quality: The focus on stronger clinical evidence may ultimately produce more robust and credible datasets.
• Long-Term Advantage: Aligning with IVDR now builds a more resilient and future-proof regulatory strategy for the EU market.

IVDR Compliance: What Sponsors Should Be Doing Now

Start Early: Given the notified body capacity constraints, begin IVDR compliance planning well in advance of your trial timelines.

Audit Your Device Portfolio: Map your IVD products against the new IVDR classification system. Understand which studies require updates or fresh approvals and prioritize trials based on regulatory risk.

Engage a Specialist CRO: Partner with a diagnostics-focused CRO like Lindus Health to navigate the complexities of IVDR compliance. Working with a team that understands both regulatory requirements and the operational nuances of diagnostics trials can help you avoid costly delays and streamline trial execution.

Coordinate Across Functions: Success under IVDR requires tight collaboration between clinical, regulatory, and quality teams. Break down silos early to avoid misalignment during submissions and trial execution.

Engage Early with Notified Bodies: Where applicable, start discussions with notified bodies as early as possible. Capacity remains limited, and proactive engagement can help avoid downstream delays.

Monitor Regulatory Updates: The IVDR landscape continues to evolve, with new guidance documents and clarifications being issued regularly.

What Sponsors Need to Know Moving Forward

While challenges remain with the IVDR transition, particularly around notified body capacity and regulatory interpretation, the extended timelines provide an opportunity for sponsors to adapt thoughtfully rather than being forced into reactive decision-making.

Success in the new regulatory environment will depend on early planning, expert guidance, and a thorough understanding of how IVDR requirements interact with clinical trial regulations. Sponsors who embrace these changes proactively will be best positioned to leverage Europe's evolving regulatory landscape for competitive advantage.

The message is clear: the time to prepare for IVDR is now. With timelines extending further, sponsors have a window of opportunity to get ahead of the curve and ensure their diagnostic study strategies are built for long-term success in the European market.

At Lindus Health, our diagnostics-specialized team helps sponsors design and run studies that meet IVDR requirements and generate the clinical evidence needed for market access.

Don’t let IVDR slow you down. Talk to our team today.