Long-term responders and survivors on pazopanib for advanced soft tissue sarcomas: subanalysis of two European Organisation for Research and Treatment of Cancer (EORTC) clinical trials 62043 and 62072.

Abstract

BACKGROUND:

Pazopanib recently received approval for the treatment of certain soft tissue sarcoma (STS) subtypes. We conducted a retrospective analysis on pooled data from two EORTC trials on pazopanib in STS in order to characterize long-term responders and survivors.

PATIENTS AND METHODS:

Selected patients were treated with pazopanib in phase II (n = 118) and phase III study (PALETTE) (n = 226). Combined median progression-free survival (PFS) was 4.4 months; the median overall survival (OS) was 11.7 months. Thirty-six percent of patients had a PFS ≥ 6 months and were defined as long-term responders; 34% of patients survived ≥18 months, defined as long-term survivors. Patient characteristics were studied for their association with long-term outcomes.

RESULTS:

The median follow-up was 2.3 years. Patient characteristics were compared among four subgroups based on short-/long-term PFS and OS, respectively. Seventy-six patients (22.1%) were both long-term responders and long-term survivors. The analysis confirmed the importance of known prognostic factors in metastatic STS patients treated with systemic treatment, such as performance status and tumor grading, and additionally hemoglobin at baseline as new prognostic factor. We identified 12 patients (3.5%) remaining on pazopanib for more than 2 years: nine aged younger than 50 years, nine females, four with smooth muscle tumors and nine with low or intermediate grade tumors at initial diagnosis. The median time on pazopanib in these patients was 2.4 years with the longest duration of 3.7 years.

CONCLUSIONS:

Thirty-six percent and 34% of all STS patients who received pazopanib in these studies had a long PFS and/or OS, respectively. For more than 2 years, 3.5% of patients remained progression free under pazopanib. Good performance status, low/intermediate grade of the primary tumor and a normal hemoglobin level at baseline were advantageous for long-term outcome. NCT00297258 (phase II) and NCT00753688 (phase III, PALETTE).

• Authors: B Kasper, S Sleijfer, S Litière, S Marreaud, J Verweij, R A Hodge, S Bauer, J M Kerst, W T A van der Graaf
• Journal: Annals of oncology : official journal of the European Society for Medical Oncology (Ann Oncol) Vol. 25 Issue 3 Pg. 719-724 (Mar 2014) ISSN: 1569-8041 [Electronic] England
• PMID: 24504442 (Publication Type: Clinical Trial, Phase II, Clinical Trial, Phase III, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Angiogenesis Inhibitors
• Indazoles
• Placebos
• Pyrimidines
• Sulfonamides
• pazopanib
• Receptors, Vascular Endothelial Growth Factor

Topics

• Adult
• Aged
• Angiogenesis Inhibitors (adverse effects, therapeutic use)
• Disease-Free Survival
• Female
• Humans
• Indazoles
• Male
• Middle Aged
• Neoplasm Metastasis (drug therapy)
• Placebos (therapeutic use)
• Pyrimidines (adverse effects, therapeutic use)
• Receptors, Vascular Endothelial Growth Factor (antagonists & inhibitors)
• Retrospective Studies
• Sarcoma (drug therapy, mortality)
• Sulfonamides (adverse effects, therapeutic use)
• Treatment Outcome