Treatment persistence and overall survival in myelofibrosis treated with ruxolitinib were not affected by the covid-19 pandemic, despite the reduced starting dose: Analysis of AIFA registries.

We analyzed the outcome of 2229 patients with myelofibrosis (MF) treated with ruxolitinib before and after the COVID-19 pandemic. Two populations of MF were defined from the AIFA web monitoring registries: the pre-COVID-19 (1703, 76.4%) and the post-COVID-19 (526, 23.6%) cohorts. The two populations were balanced using the Inversity Probability of Treatment Weighting. The median age was 69 years and 73 years in the pre- and post- COVID-19 era, respectively. There were no differences in spleen diameters at baseline prior to ruxolitinib in the two groups, but a difference in median spleen volume was noted (961 cm3 in the pre-era and 788.3 cm3 in the post-era). Overall, intermediate-2 IPSS risk were 67.2% in the pre- and 72% in the post-era, whereas the high-risk category was 32.7% and 27.9%, respectively. More patients started on a reduced dose in the post-COVID-19 era (73.5% versus 65% in the pre-era). After adjusting for the differences, an analysis of overall survival revealed no differences between the two groups (HR 0.875, p > 0.05). Patients who started ruxolitinib after COVID-19 had similar probability to stop treatment in the follow-up (HR 0.956, p > 0.05). The results indicate that COVID-19 did not affect the duration of treatment and the relative OS.