Avexis Inc. made it out the door with an upsized IPO, pricing 4.75 million common shares at $20 apiece – the midpoint of its intended range – to raise $95 million. But the company's shares (NASDAQ:AVXS) encountered headwinds as soon as they stepped off the stoop, falling as much as 20 percent early and closing at $18.05 for a loss of $1.95, or 9.8 percent, on another down day in the broader markets that included a 2.4 percent fall-off in the Nasdaq Biotechnology Index, which closed at 2,572.84.