Shares of biotech Denali Therapeutics Inc. soared more than 20% in their trading debut Friday, after the company priced its initial public offering at the midpoint of its $17 to $19 price range. The company sold 13.9 million shares at $18 each to raise $250 million, giving it a valuation of $1.7 billion, according to Renaissance Capital, a manager of IPO-focused ETFs like the Renaissance IPO ETF . Goldman Sachs, Morgan Stanley and J.P. Morgan were lead managers on the deal. The stock is trading on Nasdaq under the ticker symbol "DNLI".