New German guideline reshapes how doctors diagnose and treat primary myelofibrosis

Myelofibrosis is a rare clonal disorder of blood-forming stem cells. It causes progressive bone marrow scarring, anemia, enlarged spleen, and constitutional symptoms, and it can shorten life. Treatment decisions have grown more complex as diagnostics and drugs have evolved, so consensus guidance matters for clinicians.

This paper is an expert guideline from German-speaking hematology specialists, not a new clinical trial. Based on the abstract, it reviews the disease's definition, the 2022 WHO and ICC diagnostic criteria, prognostic factors, and treatment options. These criteria separate prefibrotic primary myelofibrosis, often presenting with isolated high platelet counts, from overtly fibrotic disease, where anemia and splenomegaly are more common at diagnosis.

Key points include that prognosis depends on age, symptoms, blood counts, and genetics. Common causes of death are transformation to acute myeloid leukemia, infections, and cardiovascular complications. Allogeneic stem cell transplantation is the only potentially curative treatment, generally recommended for transplant-eligible patients in the high or very-high risk groups of MIPSS70+ v2.0. Ruxolitinib is the standard oral therapy. Fedratinib has been EU-approved since 2021, though Swissmedic did not extend its approval. Momelotinib, approved in the EU since 2024, is particularly effective for patients with symptomatic moderate to severe anemia.

For practice, the guideline supports risk-adapted care: transplant evaluation for higher-risk patients and JAK inhibitor selection guided by symptoms and anemia. Emerging JAK inhibitors, combinations, and novel agents look promising but are not yet routine.

Caveats: only the abstract was available, so detailed recommendations, evidence grading, and dosing are not covered here. Guidelines reflect expert consensus and regional drug approvals, and several authors report extensive industry relationships.