Plus Therapeutics (PSTV) shares dipped 4.80% to $3.17 amid broader market weakness, despite a pivotal regulatory win. The American Medical Association granted a Proprietary Laboratory Analyses CPT code (0640U) for the company's CNSide cerebrospinal fluid tumor cell test, effective July 1, 2026. This establishes a standardized billing framework that streamlines reimbursement and accelerates adoption in clinical settings.

The coding decision removes administrative friction for healthcare providers, enabling cleaner claims submission and faster coverage decisions. It comes as Plus Therapeutics expands the U.S. commercial rollout of CNSide, its liquid biopsy platform for central nervous system malignancies. While short-term price action reflects market volatility, the structural tailwinds from improved reimbursement pathways strengthen the diagnostic's revenue trajectory.