The WHO Emergency Use Listing Procedure (EUL) (formerly the Emergency Use Assessment and Listing procedure (EUAL)) is a risk-based procedure for assessing and listing in vitro diagnostics (IVDs) (as well as medicines and vaccines) that have not (yet) undergone stringent regulatory assessment and that are intended for use primarily during public health emergencies of international concern (PHEICs), or in other public health emergencies. During such times communities and public health authorities may be willing to tolerate less certainty about the quality, safety and performance of products, given the morbidity and/or mortality of the disease, and the need for diagnostics. The EUL process is based on an essential set of available quality, safety and performance data.

The EUL is not equivalent or an alternative to WHO prequalification, and should not be thought of as such. The main reason for not qualifying for prequalification is that the product concerned will, at the time of submission for EUL, not fall within the scope of prequalification. WHO Member States alone hold the authority to decide whether or not to allow the emergency use of in vitro diagnostics in their country.

Eligibility

In order to qualify for an EUL, the IVD must meet the following criteria:

• be intended to detect a disease (or related analytes, as appropriate) that has been declared by WHO's Director-General to be a PHEIC, or judged to be otherwise  in the best interest of public health.
• the disease for which the product is intended is serious or immediately life threatening, causing an outbreak, epidemic or pandemic and for which there is no licensed product for the indication or for a critical subpopulation (e.g. children)
• the product is manufactured under a functional quality management system
• be intended for completion of development (validation and verification) and submission WHO prequalification; ideally, performance studies will already be under way at the time of the application for an EUL.

Evaluation procedure

Evaluation will determine whether, in light of available WHO/international standards, the submitted data demonstrate a reasonable likelihood that the IVD's quality, safety and performance are acceptable and that the benefits outweigh the foreseeable risks and uncertainties in the context of a PHEIC.

Duration of validity of an EUL

The validity of an EUL in the context of a public health emergency will generally be for a maximum of12 months. All EUL decisions are reassessed within 12 months (or sooner, if further data or other information become available that could alter the original opinion). When deemed necessary and warranted based on available data and information, the emergency use listing can be extended. Products may have their EUL status removed if new data or information becomes available that changes the benefit‒risk profile of the product, or immediately upon declaration by WHO's Director-General that the relevant PHEIC not longer exists. Manufacturers are required to supply any new information/data to WHO as soon as it becomes available.

WHO reserves the right to:

• terminate an assessment, if the applicant fails to provide WHO with all the required information
• delist a product in case of fraud, misrepresentation, withholding of information by the applicant/manufacturer.

Post-market surveillance

For products granted an EUL, appropriate post-EUL monitoring mechanisms should be established to allow for the timely evaluation of adverse events (AEs) and notification to WHO and the relevant national regulatory authorities. If a quality/safety/performance issue cannot be resolved to WHO's satisfaction, WHO reserves the right to restrict or revoke the emergency use listing of the product.

Post-EUL changes

Once a product has been listed under the EUL procedure, development of the product should continue to completion for prequalification, whenever possible. Changes to the product proposed after the product has been listed in the EUL, or delisted, should be submitted to WHO. Changes to products listed based on an abridged procedure must have been accepted by the original national regulatory authority responsible for the oversight of the product, and WHO must be notified of the accepted changes. (Some submissions submitted for WHO EUL may have undergone a previous assessment through other emergency mechanisms, for example, the US FDA Emergency Use Authorization process. Where this is the case, it is not the intent of WHO to undertake duplicative work, if the review of the other emergency mechanism is deemed to be of a satisfactory standard.)