Consequences and impacts of PEG-IFNα2a shortage: first lessons from a MPN French center

Between March to December 2024, we observed a PEG-IFNα2a shortage in France for MPN patients. We identified and followed 90 patients from our center and observed 80% of difficulties obtaining the drug, and 61 patients among all (67.8%) did not receive their prescribed drug on time (impacted group). Twenty-one patients need to reduce the dosage of PEG-IFNα2a and 27 stopped the drug. Ten clinical events were identified with nine in the impacted group (p=0.04). No hematological or only partial responses were more frequent in the impacted group (p=0.01). The allelic burden variations were also studied during this period; 17 patients obtained a VAF <10%. Eight patients stopped the drug because of VAF <4% and remained with molecular response. Three-quarters of the patients experimented with psychological and financial impacts of shortage. This study is the first one to explore a shortage of cytoreductive drugs happened in MPN. Much informations will be helpful for clinicians.