ONC Proposals in CMS Interoperability and Prior Authorization for Drugs Proposed Rule

April 2026

Overview

The Office of the National Coordinator for Health Information Technology (ONC) partnered with CMS on the Interoperability and Prior Authorization for Drugs Proposed Rule, published April 10, 2026. ONC is proposing to adopt a series of implementation specifications related to the exchange of clinical and administrative data.

Adoption of Standards for Patient, Provider, and Payer APIs

ONC is proposing to adopt updated versions of implementation specifications previously adopted in the HTI-4 final rule released in July 2025, as well as proposing to adopt a new implementation specification related to the exchange of attachments with payers. The standards proposed for adoption are:

• HL7 FHIR® Da Vinci—Coverage Requirements Discovery (CRD) Implementation Guide, Version 2.2.1—STU 2.2
• HL7 FHIR® Da Vinci—Documentation Templates and Rules (DTR) Implementation Guide, Version 2.2.0—STU 2.2
• HL7 FHIR® Da Vinci—Prior Authorization Support (PAS) FHIR Implementation Guide, Version 2.2.1—STU 2.2
• HL7 FHIR® CARIN Consumer Directed Payer Data Exchange (CARIN IG for Blue Button®) Implementation Guide, Version 2.2.0—STU 2.1
• HL7 FHIR® Da Vinci Payer Data Exchange (PDex) US Drug Formulary Implementation Guide, Version 2.1.0—STU 2.1
• HL7 FHIR® Da Vinci Payer Data Exchange (PDex) Plan Net Implementation Guide, Version 1.2.0—STU 1.2
• HL7 FHIR® Da Vinci—Clinical Data Exchange (CDex) Implementation Guide, Version 2.1.0—STU 2.1

Under ONC’s proposals, previously adopted versions of these standards would expire by January 1, 2028, after which implementers would need to use updated versions where use of the standards is required.

For instance, three of these specifications (CRD, DTR, PAS) support the certification criteria ONC finalized for electronic prior authorization in the HTI-4 Final Rule. In addition, CMS has proposed to require the proposed specifications as technical requirements for APIs established by payers under CMS regulations that focus on patient and provider access to payer data, payer-to-payer data exchange, electronic prior authorization services, and availability of provider directory information.