SB 5594 Washington Senate · 2025-2026 Regular Session

Concerning biosimilar medicines.

This bill aims to reduce prescription drug costs by improving patient access to biosimilar medicines and other prescribed drugs. It directly affects health plans, drug utilization management entities, patients, and healthcare providers. The bill establishes a clear process for patients and practitioners to request exceptions to prescription drug utilization management rules, such as prior authorization or step therapy. It outlines specific conditions under which these exception requests must be granted and sets strict deadlines for health plans to respond. If a response is not provided within the specified timeframes, the exception request is automatically granted, and health plans must cover an emergency supply fill if necessary during the process.

Issues: ✓ Healthcare

Bill status passed 3 of 5 stages cleared

Introduction

Jan 2026

Committee Review

Feb 2026

Senate Passage

Jan 2026

House Passage

Governor

Introduced Jan 12, 2026 Last action Mar 12, 2026

Maddy AI version diff · 3 comparisons

What changed between versions

Substitute Bill → Engrossed Substitute Bill · 4 edits · Jan 21, 2026

MODERATE

The bill was reclassified from a 'Substitute' to an 'Engrossed Substitute' version, indicating it has passed through additional legislative stages. The primary policy change is the expansion of the bill's title to explicitly include 'interchangeable biological products' alongside biosimilars, broadening the scope of drugs covered by the new access rules. Additionally, the text of RCW 69.41.125 was modified to change the substitution requirement from a mandatory 'must' to a permissive 'may' under specific cost conditions, and the criteria for substitution now explicitly compares the consumer's out-of-pocket costs rather than just wholesale prices.

Scope change

The bill's scope was expanded to explicitly include interchangeable biological products in addition to biosimilar medicines, and the legal standard for pharmacist substitution was adjusted to consider consumer out-of-pocket costs instead of wholesale prices.

SCOPE

The bill title and scope were expanded to explicitly include 'interchangeable biological products' in addition to biosimilar medicines.

REQUIREMENT

The requirement for pharmacists to substitute interchangeable biological products was changed from mandatory ('must') to permissive ('may') when the consumer's out-of-pocket cost for the substitute is lower.

The criteria for pharmacist substitution was updated to compare the consumer's out-of-pocket costs for the biological products, rather than comparing wholesale prices.

TECHNICAL

The bill was reclassified from 'Substitute' to 'Engrossed Substitute,' reflecting its progression through the legislative process.

Floor votes · Senate Mar 11, 2025

How they voted

51–0

Passed

Total votes 51

Mar 11, 2025

D Democratic31

31 Yea

100% Yea

R Republican20

20 Yea

100% Yea

Vote distribution

All Yea All Nay Mixed No data

Full legislative history

Actions timeline

Total actions

Key actions

Committee

Feb 25, 2026

Committee

Referred to Rules 2 Review.

lower

Feb 25, 2026

Lower · Passed

HCW - Majority; do pass.

lower

Feb 25, 2026

Lower · Passed

Executive action taken in the House Committee on Health Care & Wellness at 1:30 PM.

lower

Feb 10, 2026

Lower · Passed

Public hearing in the House Committee on Health Care & Wellness at 8:30 AM.

lower

Jan 21, 2026

Upper · Passed

Floor amendment(s) adopted.

upper

Jan 19, 2026

Upper · Passed

Rules Committee relieved of further consideration.

upper

Jan 12, 2026

Introduced

By resolution, reintroduced and retained in present status.

upper

Apr 1, 2025

Lower · Passed

Executive session scheduled, but no action was taken in the House Committee on Health Care & Wellness at 1:30 PM.

lower

Mar 26, 2025

Lower · Passed

Public hearing in the House Committee on Health Care & Wellness at 1:30 PM.

lower

Mar 11, 2025

Upper · Passed

Floor amendment(s) adopted.

upper

Feb 18, 2025

Upper · Passed

Executive action taken in the Senate Committee on Health & Long-Term Care at 10:30 AM.

upper

Feb 11, 2025

Upper · Passed

Public hearing in the Senate Committee on Health & Long-Term Care at 10:30 AM.

upper

1 primary · 3 co-sponsors