CA SB853

Expands prohibitions on limiting prescription drug coverage to include dose and dosage form restrictions for health care service plans and disability insurers, effective for contracts issued, amended, or renewed on or after January 1, 2023.

Requires health care service plans and disability insurers to cover previously approved prescription drugs during the entire utilization review and appeals process if the drug was previously covered and is currently prescribed by a provider.

Classifies reduction or termination of an ongoing, approved course of treatment as an adverse benefit determination and requires insurers to provide written notice at least 7 calendar days before the effective date of the change.

Mandates continuing coverage during all internal and external appeals of treatment denials, including successive appeals, while allowing plans to continue applying standard cost-sharing requirements.

Expands the definition of "life-threatening" and "chronic and seriously debilitating" conditions to explicitly include mental health and substance use disorders for purposes of off-label drug coverage determinations.