The present article outlines the key points related to the existing legal framework and explains the basics of the approach to be followed. 

FDA Guidance

The Food and Drug Administration (FDA or the Agency), the US regulating authority in healthcare products, has published a draft guidance document dedicated to the characterization of metallic coatings and/or calcium phosphate coatings on orthopedic devices.

Once finalised, the document will provide an overview of the applicable regulatory requirements, as well as additional clarifications and recommendations to be considered by medical device manufacturers and other parties involved to ensure compliance to it.

At the same time, provisions of the guidance are non-binding in their legal nature, nor are they intended to introduce new rules or impose new obligations.

Moreover, the authority explicitly states that an alternative approach could be applied, provided such an approach is in line with the existing legal framework. It has been agreed with the authority in advance. 


The present draft guidance describes in detail the authority’s current position and recommendations for premarket submissions concerning orthopedic devices embellished with metallic and/or calcium phosphate coatings.
This document is addressed to industry stakeholders, outlining the expectations and review practices to ensure uniformity and expedite the review process.

The document also references the FDA-recognised voluntary consensus standards the parties involved may use when demonstrating compliance with the applicable regulatory requirements.

Such an approach reduces the regulatory burden faced by the parties interested in placing their products on the US market.

FDA on assessing credibility of computational modelling2

Scope and Applicability

The scope of this guidance is limited to Class II and Class III orthopedic devices that incorporate metallic and/or calcium phosphate coatings. The document elaborates on the characterizations of these coatings, which can be fabricated using various methods including but not limited to thermal spray, sintering, vapor deposition techniques, and additive manufacturing. It is important to note that the guidance explicitly excludes coatings containing drugs or biological materials and does not provide additional details on device-specific functional testing.

The guidance also provides a roadmap for compliance with specific regulatory frameworks and controls applicable to the devices under discussion.
It encourages adherence to the latest FDA-recognized consensus standards, emphasizing that such compliance is deemed to satisfy or even exceed the requirements outlined in unique controls.

Detailed Recommendations for Premarket Submissions

The document further provides detailed recommendations to be followed by the parties responsible for medical devices when preparing premarket submissions.

  1. Describing the Coating: In the context of premarket submissions, the authority expects the applicants to ensure a comprehensive delineation of the coatings applied to orthopedic devices.
    This includes specifying the name and type of coating, the manufacturing processes employed, and a detailed account of the starting materials.
    The document suggests including information on the physical structure of the coating, such as layering, thickness, and porosity, alongside engineering drawings to illustrate the coating’s coverage on the device.
    This section is crucial for submissions involving coatings applied by third parties, recommending the inclusion of a letter of authorization from the master file holder to streamline the review process.
  2. Sterilization Protocols: Acknowledging the critical importance of sterilization for implanted devices, the guidance emphasizes the necessity of presenting detailed sterilization protocols in premarket submissions.
    It outlines the expectation for devices to be delivered sterile, emphasising the potential impact of end-user handling on the integrity and cleanliness of the coating.
    The document outlines the sterilization methods, including a thorough description of the process, the validation of the sterilization cycle, and the specific considerations for different sterilization techniques such as radiation and chemical sterilants.

For devices coated with calcium phosphate, the guidance recommends gamma radiation sterilization, referring to its historical clinical use and supporting data that attest to its compatibility with the coating properties.
It also addresses the need for presenting a rationale if alternative sterilization methods are proposed, ensuring they do not compromise the coating’s integrity or clinical efficacy.


The draft guidance describes the FDA’s efforts to establish an efficient and predictable premarket submission process for orthopedic devices with coatings.
It serves as a comprehensive resource for industry stakeholders, offering additional clarifications and recommendations related to compliance and regulatory approval procedures medical devices in question are subject to.
It is essential to mention that this guidance not only intends to streamline the review process but also contributes to public health protection by ensuring the reliability and sterility of orthopedic devices entering the market.

How Can RegDesk Help?

RegDesk is a holistic Regulatory Information Management System that provides medical device and pharma companies with regulatory intelligence for over 120 markets worldwide. It can help you prepare and publish global applications, manage standards, run change assessments, and obtain real-time alerts on regulatory changes through a centralized platform. Our clients also have access to our network of over 4000 compliance experts worldwide to obtain verification on critical questions. Global expansion has never been this simple.