Efficacy demonstrated in the PIONEER clinical trial1
AYVAKIT demonstrated statistically significant improvements vs placebo for primary and key secondary endpoints in the PIONEER study1
|AYVAKIT + BSC (N=141)
|Placebo + BSC (N=71)
|2-sided P value
|Absolute mean change in the ISM-SAF TSS (95% CI)
ITT analysis: Markov chain Monte Carlo simulation was used to impute the missing values.
LIMITATIONS: Mean change in TSS at all time points except Week 24 were prespecified, nonranked endpoints and were not adjusted for multiplicity. Therefore, treatment differences at these time points cannot be regarded as statistically significant and results should be interpreted with caution.
ITT=intention to treat.
- Reductions were observed in patients’ most severe symptom, defined as the symptom with the highest score at baseline9
ITT analysis: In this analysis, if a patient was missing more than 7 days of the score between baseline score and Week 2 score, it was considered as missing for the patient. If a patient missed more than 7 days of the score from the 14-day period for calculating the Week 24 score, then the Week 24 score was considered as missing.
LIMITATIONS: Individual components in a descriptive exploratory analysis were prespecified, nonranked endpoints, not adjusted for multiplicity, and not powered. Therefore, data should be interpreted with caution, conclusions cannot be drawn, and treatment differences cannot be regarded as statistically significant.
ITT analysis: Patients with use of high-dose steroids (3 patients treated with AYVAKIT and 1 in the placebo group) were included in this analysis that were not included in the primary analysis.
Missing visit data were excluded from calculations for that visit.
- In an interim analysis, a decrease in TSS was observed for patients who continued on AYVAKIT in an OLE through 48 weeks9
LIMITATIONS: Mean change in TSS at all time points except Week 24 were prespecified, nonranked endpoints and were not adjusted for multiplicity. Therefore, treatment differences at these time points cannot be regarded as statistically significant, results should be interpreted with caution, and conclusions cannot be drawn. In an open-label extension, there is a potential for enrichment of the long-term data in the remaining patient populations since patients who were unable to tolerate or do not respond to the drug often drop out.
ITT analysis: For patients with high-dose steroid use within 7 days before Week 24, or greater than 14 consecutive days at any point from baseline to Week 24, the Week 24 score was set to missing.
†Percent of patients with ≥50% reduction in peripheral blood KIT D816V VAF or undetectable.
‡Percent of patients with ≥50% reduction in BM MCs or no aggregates.
BM=bone marrow; BSC= best supportive care; MC=mast cell; VAF= variant allele fraction.