SUMMIT, NJ ( TheStreet) -- The addition of Celgene's ( CELG) cancer drug Abraxane to the chemotherapy drug gemcitabine prolonged the survival of patients with advanced pancreatic cancer by slightly less than two months over treatment with gemcitabine alone, according to results from a phase III study released Tuesday night. Patients treated with the Abraxane-gemcitabine regimen reported a median overall survival of 8.5 months compared to 6.7 months for patients treated with gemcitabine. That works out to a survival benefit of 55 days, or a day shy of eight weeks. Celgene announced the detailed Abraxane results in conjunction with the lifting of an embargo on research abstracts to be presented at an American Society of Clinical Oncology meeting focused on gastro-intestinal cancer research that starts Thursday. The eight-week survival benefit offered by Abraxane is in line with investor expectations, according to a survey conducted last week by ISI Group analyst Mark Schoenebaum. Celgene shares closed Tuesday down less than 1% to $99.31 ahead of the Abraxane data announcement. In after-hours trading, the stock fell another 1% to $98.25 Celgene has been the highest-flying large-cap biotech stock this year -- up 27% to date -- due to high expectations for accelerating revenue growth (from Abraxane and other drugs) plus optimism about the company's late-stage drug pipeline. The Celgene contingent value right ( CELGZ) tied to Abraxane closed Tuesday up 3% to $7.50, an all-time high. Abraxane sales could reach $1 billion to $1.25 billion by 2015, Celgene forecast at the J.P. Morgan Healthcare Conference on Jan. 7. Abraxane is approved currently for breast cancer but Celgene plans to seek FDA approval for an expanded label in lung cancer and pancreatic cancer. Final Abraxane sales for 2012 have yet to be released but will likely total around $400 million. Biotech investors, click here to visit TheStreet's 2013 FDA and EMA drug approval decision calendar. Abraxane is a novel reformulation of the old chemotherapy drug paclitaxel. In this latest study, 861 treatment-naive pancreatic cancer patients were randomized to treatment with Abraxane plus the chemotherapy gemcitabine or gemcitabine alone. Celgene designed the pancreatic cancer study to show an approximate two-month survival advantage for Abraxane plus gemcitabine over gemcitabine alone. Historically, patients treated with gemcitabine alone live about six months.