Shares of BriaCell Therapeutics Corp. more than doubled Wednesday on heavy volume, after the biotechnology company provided upbeat update on its breast cancer treatment. The stock soared 104% to pace all gainers on major U.S. exchanges, while trading volume spiked to 14.9 million shares, compared with the full-day average over the past 30 days of about 520,000 shares. The company the average overall survival benefit was 12.0 months, with a top-responder survival of 21.4 months plus 100% resolution of “eye-bulging” tumor, which compares with average 7.2 months to 9.8 months survival in historical comparison treatment trials. The stock has now gained 55.4% year to date, while the iShares Nasdaq Biotechnology ETF has slipped 0.2% and the S&P 500 has advanced 12.0%.

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