Avapritinib for treating advanced systemic mastocytosis

Advanced systemic mastocytosis is a rare, KIT D816V-driven haematologic neoplasm characterized by mast cell infiltration and shortened survival (1).

• is a rare myeloid neoplasm, driven by the KIT D816V mutation in >90% of patients (2)
• the increased proliferation and accumulation of neoplastic mast cells, leads to severe, debilitating and often unpredictable symptoms and poor quality of life (QoL)
• characterized by proliferation and accumulation of mast cells in the bone marrow, skin, and visceral organs
  • mast cell infiltration leads to organ damage, referred to as ‘C-findings’ (that is, cytopenias or liver dysfunction), with limited treatment options and poor survival (1)

Avapritinib

• is a highly selective inhibitor of the KIT D816V mutation

NICE states that (3):

• avapritinib is recommended, within its marketing authorisation, as an option for treating advanced systemic mastocytosis (including aggressive systemic mastocytosis, systemic mastocytosis with an associated haematological neoplasm and mast cell leukaemia) in adults

Reference:

1. Gotlib J et al. Efficacy and safety of avapritinib in advanced systemic mastocytosis: interim analysis of the phase 2 PATHFINDER trial. Nat Med. 2021 Dec;27(12):2192-2199.
2. Reiter A et al. Efficacy and safety of avapritinib in previously treated patients with advanced systemic mastocytosis. Blood Adv. 2022 Nov 8;6(21):5750-5762.
3. NICE (November 2024). Avapritinib for treating advanced systemic mastocytosis