Early initiation of ruxolitinib (within the first 12 months after diagnosis) appears beneficial for patients with myelofibrosis, improving overall survival and reducing cytopenia events, according to a recently published study in Cancer.

The efficacy of the Janus kinase 1 (JAK1)/JAK2 inhibitor ruxolitinib has already been demonstrated in the randomized, phase 3, controlled myelofibrosis study with oral JAK inhibitor treatment 1 (COMFORT-1) and COMFORT-2 clinical trials, the researchers noted. However, it remains unclear whether an earlier beginning of treatment positively affects final outcomes in patients of all prognostic categories, they added.

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“The objective of this analysis was to assess the association between MF disease duration before ruxolitinib treatment and disease outcomes by using pooled data from the randomized, phase 3 COMFORT-1 and COMFORT-2 studies,” the authors wrote.

Kaplan–Meier analyses and Fisher exact were used to compare patients receiving treatment less than a year after diagnosis to those receiving later treatment.

The trial included 525 patients with intermediate or high-risk myelofibrosis that were divided into a control group that received ruxolitinib and a placebo group. Patients from the placebo group that experienced worsening splenomegaly were allowed to switch groups. Patients that switched groups were not included in the posthoc analysis.

The authors observed that a lesser proportion of patients that received ruxolitinib during the first 12 months after diagnosis developed cytopenias than patients that received treatment later. Similarly, spleen size reduction was more frequent in patients that received early treatment.

Overall survival at week 240 was 68% in the group that received early treatment, while in the late treatment group was 57%, which was considered statistically significant after analysis. Improved overall survival compared to patients receiving a placebo regardless of disease duration was also observed.

“Although watch and wait remains a common management approach for newly diagnosed patients, these data suggest that patients with MF may benefit from earlier intervention,” the authors concluded.


Verstovsek S, Kiladjian JJ, Vannucchi AM, et al. Early intervention in myelofibrosis and impact on outcomes: a pooled analysis of the comfort‐i and comfort‐ii studies. Cancer. Published online February 25, 2023. doi:10.1002/cncr.34707