Long-term givinostat safe, effective in polycythaemia vera

Givinostat, a histone-deacetylase inhibitor, is safe and effective for long-term use in patients with polycythaemia vera (PV), a recent study has found.

The present study looked at the 4-year mean follow-up of an open-label study, involving five PV patients (median age 59.0 years, 62.0 percent men) who had been previously shown to benefit from givinostat. All participants remained on treatment at the last effective and tolerated dose. The primary study outcome was long-term safety, tolerability, and efficacy.

Four patients were nonresponders at enrolment but were nevertheless included because of improvements in disease-related symptoms and haematological parameters upon compassionate use of givinostat.

Forty-eight participants experienced at least one adverse event (AE), yielding a rate of 96.0 percent. Most of the AEs were below grade 3 (89.7 percent). The same was true for side effects considered to be treatment-related. Only five patients developed grade 3 events; no AEs grade 4 or 5 were recorded.

In terms of efficacy, rates of treatment response, either partially or completely, were consistently above 80 percent over the entire duration of follow-up. Overall response was higher in those receiving givinostat monotherapy than in patients with concomitant hydroxyurea use.

“PV is a BCR-ABL1-negative myeloproliferative neoplasm characterized by excessive proliferation of erythroid, myeloid, and megakaryocytic components in the bone marrow, mainly due to a Janus kinase 2 gene mutation,” the researchers explained. Givinostat works by selectively inhibiting cell growth of cells bearing such a mutation.

“In conclusion, givinostat was confirmed to have a good safety and efficacy profile in patients with PV, with data supporting long-term use in this population,” they added.