Board declines to add MPS II (Hunter syndrome) to newborn screening panel, citing limited long‑term outcome data

The Washington State Board of Health voted not to add MPS II (Hunter syndrome) to the state newborn screening panel, concluding that available evidence did not yet justify the addition.

The technical advisory committee (TAC) that reviewed MPS II was split: TAC members found that screening technology and diagnostic tests exist, but they flagged missing long‑term outcome data needed to quantify the benefit of newborn screening. Megan McCrillis, a DOH policy analyst, summarized the TAC’s findings and cautioned that published outcome data remain limited.

“This condition happens to be genetically x‑linked… Symptoms can include learning or thinking problems, breathing issues, bone and joint problems, hearing loss, hernias, and poor growth,” McCrillis said during the presentation, noting the condition’s rarity and variable severity.

Committee members also emphasized treatment and cost considerations: enzyme replacement therapy (ERT), the historical standard of care, has an average annual drug cost cited in materials at about $500,000 per year. TAC members said the program could likely screen using existing lab technology but that implementation requires additional laboratory and clinical staffing.

Board members weighed the uncertainty about whether initiating treatment earlier in a newborn (versus clinical diagnosis at age 2–4) measurably improves long‑term outcomes. After discussion, the board voted not to move forward with adding MPS II to the panel at this time; members directed staff to note the committee’s recommendations and to revisit the issue if new evidence or funding emerges.

The decision preserves the board’s option to reconsider future petitions or TAC recommendations, but it prevents immediate rulemaking or CR101 filing to add MPS II.