Further exploration is needed to uncover solutions that are able to control BOTH THE SYMPTOMS AND THE UNDERLYING DISEASE1,2

Current and potential future goals for managing myelofibrosis could include1-6:

An illustrations of a spleen visualizing spleen volume reduction as a treatment management goal

Sustained reduction of spleen volume

An illustration visualizing improved symptom responses as a result of successful myelofibrosis management

symptom responses

A calendar icon visualizing anemia response for longer transfusion-free periods as a result of successful myelofibrosis management

for longer transfusion-free periods

An illustration of a bone visualizing the reversal of bone marrow fibrosis as a result of successful myelofibrosis management

Reversal of
bone marrow fibrosis

An illustration visualizing reduced variant allele frequency burden as a result of successful myelofibrosis management


An illustration visualizing improved overall survival as a result of successful myelofibrosis management


In a US MPN Landmark survey, the most important treatment goal for patients with myelofibrosis was to slow or delay disease progression7

  • Other important goals for patients included better quality of life, healthy blood counts, and symptom improvement7

A closer look at some potential management goals:

Sustained reduction of spleen volume

JAK inhibition typically achieves SVR ≥35% in ≈40% of patients at 24 weeks8,9

The majority may not sustain SVR10

An illustration symbolizing the percentage of patients that don't sustain spleen volume reduction

≈70% did not sustain SVR at ≈3 years
(Landmark clinical trial)10

≈70% did not sustain SVR at
≈3 years
(Landmark clinical trial)10

Anemia response for longer transfusion-free periods

All patients with MF are at risk of developing anemia3

At diagnosis, nearly 40% of patients with MF have hemoglobin (Hb) levels <10 g/dL and nearly one-quarter are already RBC transfusion dependent3

An illustrations of a blood drop visualizing durable anemia response as an outcome of successful treatment management

In some patients, durable anemia response could help mitigate symptoms or allow for longer transfusion-free periods, improving quality of life3,11

Reversal of bone marrow fibrosis

BMF is a key diagnostic feature (2008 WHO criteria) of MF12

In a long-term follow-up study, reduced BMF* with JAK inhibition was correlated with:

An illustrations of a spleen visualizing spleen volume reduction as a treatment management goal

Increased SVR13

An illustration symbolizing the management goal of decreased leukoerythroblastosis

Decreased leukoerythroblastosis13

Targeting the malignant stem cell may disrupt the downstream signaling that contributes to BMF2,5,14

Reduced variant allele frequency (VAF)15-18

VAF refers to the allelic burden in mutations such as JAK2 V617F that are present in myelofibrosis and other MPNs15,16,18

In some studies, reductions in VAF have been associated with clinical improvements, such as:

Reversal of BMF16,18

An illustrations of a spleen visualizing improved spleen response as an outcome of successful treatment management

Reduction in spleen volume17

The heterogeneity of treatment experiences, durations, and response definitions continues to pose clinical challenges19

Assessing myelofibrosis response

Definitions of optimal myelofibrosis response are variable and lack clinical consensus; however, some factors to consider may include19:

An illustration symbolizing the target reduction in spleen size, and persistence of constitutional symptoms during therapy

Target reduction in19:

  • Spleen size
  • Persistence of constitutional symptoms during therapy
An illustration of the time to (and degree of) clinical improvement

Time to (and degree of) clinical improvement19:

  • Monitoring response during the first 3 to 6 months of treatment may help inform the approach moving forward

Per IWG-MRT response criteria, benefit must last for ≥12 weeks to qualify as a response20

Rethink the ways we look at myelofibrosis and disease progression5,21,22

AbbVie is committed to ongoing research in myelofibrosis.

*Measured by grade of reticulin and collagen deposition.13

BMF=bone marrow fibrosis; IWG-MRT=International Working Group-Myeloproliferative Neoplasms Research and Treatment; JAK=Janus kinase; JAK/STAT=Janus kinase signal transducer and activator of transcription; MF=myelofibrosis; MPN=myeloproliferative neoplasm; RBC=red blood cells; SVR=spleen volume reduction; WHO=World Health Organization.


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