Significant Bone Density Improvements Observed
Recent data from the phase 2 PATHFINDER study (NCT03580655) presented at the 2024 ASH Annual Meeting has shown that avapritinib (Ayvakit) leads to significant and sustained improvements in bone density among patients with systemic mastocytosis. This breakthrough is particularly notable for patients suffering from advanced systemic mastocytosis, a condition that often leads to severe bone complications.
Key Findings
- Improvement in Lumbar T-scores: Among patients who underwent serial bone dual-energy X-ray absorptiometry (DXA) scans, those with low bone density (BDlow) saw their T-scores improve from -2.44 at baseline to -1.63 at their last visit (P = .034).
- Stabilization Across Cohorts: Patients with normal (BDnorm) and high bone density (BDhigh) experienced stabilized mean lumbar T-scores, indicating the drug's broad efficacy.
- Myelofibrosis and Osteosclerosis Improvements: Avapritinib also showed benefits in reducing myelofibrosis and osteosclerosis, further underscoring its potential as a comprehensive treatment option.
Expert Commentary
"Overall, we were able to show that osteopenia, osteoporosis, and osteosclerosis all improved with sequential measurements while on the PATHFINDER study," stated Daniel DeAngelo, MD, PhD, highlighting the significance of these findings. DeAngelo, a professor at Harvard Medical School, emphasized the importance of addressing bone disease in systemic mastocytosis, a common and debilitating comorbidity.
Study Details
The PATHFINDER study enrolled patients with advanced systemic mastocytosis, requiring them to have a confirmed diagnosis and an ECOG performance status of 0 to 3. Patients received avapritinib at doses of 100 mg or 200 mg daily, with optional DXA scans performed at baseline and approximately every 12 months during treatment.
Future Directions
While the results are promising, researchers call for further studies to explore avapritinib's potential in improving bone health, especially in patients with indolent systemic mastocytosis, where osteopenia and osteoporosis are highly prevalent.
This study represents a significant step forward in the treatment of systemic mastocytosis, offering new hope for patients suffering from this challenging condition.
