Imetelstat in MF: More research needed

None of these abnormalities were linked to clinically overt liver damage, and most patients ultimately saw their values return to baseline levels.

Adverse events that were considered at least possibly related to treatment and occurred in 3 or more patients included thrombocytopenia (45% grade 3/4), anemia (39% overall, 30% grade 3), neutropenia (27% grade 3/4), aspartate aminotransferase elevation (27% grade 1), alkaline phosphatase elevation (21% grade 1/2), elevation in total bilirubin (12% grade 1/2), infusion-related reactions (12% grade 1/2), diarrhea (9% grade 1/2), and epistaxis (9% grade 1/2).

Treatment discontinuation

At the data-cutoff date (December 5, 2014), 76% of patients had discontinued imetelstat (n=25). For all patients, the median duration of treatment was 8.6 months (range, 1.4 to 21.7).

Patients stopped treatment due to insufficient response (n=16), disease progression or relapse after response (n=3), death during the treatment period (n=2), adverse events (n=2), financial constraints (n=1), and pre-existing atrial fibrillation (n=1).

Both patients who discontinued imetelstat due to adverse events had persistent thrombocytopenia. Of the 2 deaths, 1 was considered treatment-related. That patient died of intracranial hemorrhage that was attributed to drug-induced, grade 4 thrombocytopenia after weekly dosing. The non-treatment-related death was the result of an upper gastrointestinal hemorrhage.