Design Control 101

# Introduction

For businesses involved in the manufacturing of medical devices or software integrated into medical devices (SaMD or SiMD), design controls are an indispensable component of their quality management endeavors. Design controls occupy a pivotal position in ensuring compliance with ISO 13485, ISO 14971, and IEC 62304 standards. Therefore, mastering the art of effective design control management is imperative for companies striving to bring safe and trustworthy medical devices to the market.

This article aims to demystify the complexities of design controls within the medical device regulatory framework, providing comprehensive insights into their significance in the development of medical device products.

# Definition

Design controls are a set of practices mandated by the FDA to facilitate a structured and systematic approach to the design and development of medical devices. They establish multiple checkpoints to ascertain the safety and efficacy of a device prior to market release. For manufacturers of medical devices, strict compliance with design controls is a legal requirement. In the realm of medical devices and SaMD solutions, design controls serve several critical purposes:

- Ensuring the delivery of high-quality products.

- Safeguarding user safety.

- Managing costs effectively.

- Accelerating time-to-market.

- Ensuring adherence to regulatory standards.

Design controls play a pivotal role in enhancing product quality and preventing manufacturing defects that could lead to recalls or other significant issues. Full compliance with these requirements serves as a shield against FDA warning letters and product recalls, undesirable outcomes that medical device and SaMD companies aim to avoid. Design controls provide a structured framework that guarantees meticulous planning and execution of each design phase and promotes a cross-functional approach, enabling a holistic perspective and early identification of potential obstacles. Ultimately, organizations employ design controls to ensure the development of safe and effective products for the market.

# Design Control vs. Quality Management System (QMS)

Design controls should seamlessly integrate with the broader Quality Management System (QMS). An effective QMS should encompass procedures for managing documents, records, and suppliers, with design controls serving as the glue that links these elements to specific development processes. The scope of the design and development process, governed by design controls, extends beyond device creation and testing, encompassing activities such as document creation, supplier qualification, and record maintenance. Even after the initial design phase, the QMS continues to be indispensable for ongoing compliance, as regulators mandate continuous monitoring and quality system reporting related to the device's lifecycle, including complaint handling, nonconformance monitoring, and risk management.

# Principles of Effective Design Control

Now that we have established the context of design controls within the regulatory landscape, let's delve into the intricacies of the process itself. The following elements present a generalized approach that combines FDA and ISO requirements, predominantly employing FDA terminology. Each element of design controls is meticulously evaluated by auditors, with specific considerations provided at the conclusion of each element:

A. Establish QMS Procedures

Commencing with well-structured QMS procedures lays the foundation for a smoother implementation of design controls. When organizations embark on device development without first establishing the QMS and design controls processes, several common issues may arise, including missed compliance steps, ineffective procedures, organizational disarray, resource-intensive retrospective corrections, and audit complications. Writing procedures is only part of the process; their implementation is equally crucial. Auditors scrutinize whether the organization's activities regarding design controls align with the developed procedures, emphasizing the importance of effective implementation.

B. Document Design and Development Planning

Following the establishment of QMS and design control procedures, the development of a meticulous design plan becomes paramount. Organizations often create development plans comprising distinct phases or stages that align with critical milestones. Auditors assess the adequacy of planning documents, the definition of team members, and the effectiveness and adherence to the plans.

C. Apply Risk Management

Risk management, a multifaceted process, permeates all aspects of design and development. Typically, it is applied following ISO 14971 standards, recognized by both the FDA and EU. Risk management begins early in the development process, with risks and potential harm serving as drivers for user needs and design inputs. Risk assessment remains a continuous activity, adapting as the design evolves and new considerations arise. Auditors focus on whether risk management is consistently applied throughout the design and development process and if risks are effectively mitigated during the design phase.

D. Perform Design Reviews

Design reviews serve as critical checkpoints during the design process, preventing wastage of resources on a device that may ultimately fail to meet requirements. Conducting comprehensive, cross-functional reviews at each phase and promptly addressing necessary corrective actions can forestall complications during Design Verification and Design Validation (V&V). While regulations do not prescribe specific project milestones for design reviews, organizations are entrusted with defining these milestones in their Standard Operating Procedures (SOPs). Auditors scrutinize various aspects during design reviews, including attendee records, their roles, approval of reviews, the specific stage or phase under review, minutes of the meeting with action items, and the ability to link the review to the respective device's Design History File (DHF).

E. Establish User Needs and Design Inputs

Prior to embarking on device development, it is imperative to define the device's purpose comprehensively, ensuring alignment with user expectations and organizational objectives. User needs and design inputs, although closely related, exhibit subtle distinctions. Auditors assess whether user needs and inputs are succinct, unambiguous, and free from conflicts.

F. Establish Design Outputs

Design outputs represent the characteristics of the device that translate design inputs and user needs into a tangible reality. Ensuring that design outputs align with respective inputs and verification activities is crucial. Auditors closely examine whether design outputs are linked to corresponding inputs and verification procedures within the Design History File (DHF), emphasizing the importance of maintaining up-to-date and controlled documentation.

G. Perform Design Verification and Design Validation (V&V)

Verification and validation (V&V) are imperative testing activities aimed at confirming that the device meets predefined specifications and fulfills its intended purpose. Distinguishing between verification and validation is essential:

- Design Verification: Focuses on ascertaining whether the device has been designed correctly, evaluating the attainment of design inputs and specification compliance.

- Design Validation: Evaluates whether the right device has been designed, ensuring alignment with user needs and expectations.

Several critical factors pertain to V&V, including planning, sample sizes, and the necessity of qualified individuals for well-defined tests. Organizations should exercise diligence to prevent subsequent changes to the device, which could entail the repetition of V&V activities. Auditors assess whether V&V is conducted on finished device equivalents, if sample sizes are justified using statistical techniques, and if all user needs and inputs are rigorously tested and documented within the DHF.

H. Document Design Transfer

Design transfer constitutes the final preparations for transitioning the device to commercial production. Successful design transfer equips organizations to initiate manufacturing seamlessly. This process involves connecting design documentation with manufacturing documentation, verifying the completeness of the Design History File (DHF), maintaining records of the transfer, ensuring adequate training for manufacturing personnel, and obtaining regulatory approvals before product release.

I. Completing Design Changes and the Design History File (DHF)

The FDA mandates the establishment and maintenance of a Design History File (DHF) for each device type. The DHF must encompass or reference the records necessary to demonstrate that the design aligns with the approved design plan and regulatory requirements. Organizations employ various methods to document a DHF, often utilizing a DHF Index as a comprehensive guide to the file's contents.

# Tips for Effective Design Control Implementation

a. Initiate Design Controls Early:

Design controls should commence at the intersection of research and design. Waiting too long can lead to regulatory challenges and increased costs. Embrace design controls as a means to develop a safe and successful product rather than succumbing to regulatory pressure. Cultivate a culture of quality from the outset of the design process to maintain a quality mindset throughout the device's lifecycle.

b. Embrace Digitalization:

Transition from paper-based systems to cloud-based Quality Management Systems for streamlined compliance with ISO and FDA regulations. Cloud-based systems enhance transparency, traceability, and efficiency, reducing the likelihood of errors.

c. Foster Collaboration:

Promote a unified approach that bridges the gap between quality and product development teams. Encourage collaboration, ensure common software and project tracking tools, and eliminate silos to foster synergy.

d. Seek Expert Guidance:

When initiating design controls, consider seeking expert guidance to navigate the complexities effectively. Establishing robust design controls procedures and systems from the outset can prevent future complications.

In conclusion, understanding and implementing design controls is imperative for medical device companies seeking to navigate the intricate regulatory landscape and develop safe, compliant, and successful products. Initiating design controls early, embracing digitalization, fostering collaboration, and seeking expert assistance are key strategies to achieve effective design control management.