Novartis announced the final overall survival (OS) analysis results from the phase III SOLAR‑1 study of Piqray (alpelisib), a novel breast cancer therapy, at the 2020 European Society for Medical Oncology (ESMO) Virtual Congress.
Key Efficacy Outcomes from the SOLAR‑1 Study
Data showed that in patients with PIK3CA‑mutated, hormone receptor‑positive/human epidermal growth factor receptor 2‑negative (HR+/HER2‑) advanced breast cancer (aBC), Piqray plus fulvestrant provided a clinically relevant improvement in OS of 8 months compared with fulvestrant alone. In patients with lung or liver metastases, OS was improved by more than 14 months. Lung and liver metastases are present in 41% of postmenopausal women with HR‑positive aBC and are associated with more aggressive disease and greater treatment challenges.
Clinical Significance of Piqray
Notably, Piqray is the first and only therapy specifically approved for patients with advanced breast cancer harboring a PIK3CA mutation.Data presented at this ESMO meeting provide further evidence supporting the efficacy of Piqray in patients with PIK3CA‑mutated aBC. Each year, 334,000 people are diagnosed with advanced breast cancer worldwide. Approximately 40% of patients with the HR+/HER2‑subtype have a PIK3CA mutation, which drives tumor growth and is linked to poor treatment response and unfavorable prognosis.
Previously Reported Efficacy Data
Earlier published results demonstrated that Piqray plus fulvestrant nearly doubled progression‑free survival (median PFS: 11.0 months vs 5.7 months), reduced the risk of disease progression or death by 35% (HR=0.65, 95% CI: 0.50–0.85; p<0.001), and more than doubled the overall response rate (ORR: 36% vs 16%) compared with fulvestrant alone. Subgroup analyses of PFS showed consistent efficacy regardless of lung/liver metastasis. In patients without PIK3CA mutation, Piqray plus fulvestrant did not meaningfully improve PFS.
Final OS Results from ESMO 2020
Data presented at the ESMO Congress showed that Piqray plus fulvestrant was associated with a clinically meaningful 8‑month improvement in OS compared with fulvestrant alone (median OS: 39.3 months vs 31.4 months; one‑sided p≤0.0161; HR=0.86; 95% CI: 0.64–1.15; p=0.15). This difference did not reach the threshold for statistical significance. In patients with lung or liver metastases, the improvement in OS exceeded 14 months (median OS: 37.2 months vs 22.8 months; HR=0.68; 95% CI: 0.46–1.00).
Additional Clinical Benefits
Furthermore, Piqray plus fulvestrant delayed the initiation of chemotherapy by 9 months compared with fulvestrant alone (23.3 months vs 14.8 months; HR=0.72; 95% CI: 0.54–0.95) and preserved quality of life (QOL).
Safety Profile
No new safety signals were identified. The safety profile was consistent with previously reported findings.
