AB Science leaps as GIST candidate masitinib beats Sutent

France-based AB Science (AB: EN Paris) saw its share price rocket as much as 72% to 10.60 euros after the company announced encouraging results from a Phase II study with its investigational drug, masitinib, in Gleevec (imatinib)-resistant gastrointestinal stromal tumors (GIST).

Masitinib, which is already sold by the company as a treatment for a common form of cancer in dogs, significantly improved overall survival in patients with Gleevec-resistant gastrointestinal stromal tumors (GIST) compared to Sutent (sunitinib) from global drugs behemoth Pfizer, a drug approved for second-line treatment of GIST, currently the standard of care for these patients, the French firm noted. Sutent generated sales of $1.19 billion in 2011.

In this study, 44 patients with inoperable, locally-advanced or metastatic GIST and showing disease progression while treated with Gleevec 400 to 800mg/day) received either masitinib (23 patients) at 12 mg/kg/day or Sutent (21 patients) until progression. After a median follow-up of 14 months, median overall survival was not reached for masitinib versus 15 months for Sutent (p=0.022 HR:3.2).