Vaxxinity Inc. VAXX, +20.12% started its public life with a big rally, as the Texas-based biotechnology company's stock was trading more 21.2% above its initial public offering price. The company said overnight that its IPO of 6.0 million shares, down from previous expectations of a 6.7-million share offering, priced at $13 a share, below the expected range of between $14 and $16 a share. The stock's first trade was at $16.90 at 11:52 a.m. Eastern for 263,126 shares. At that price, the company was valued at about $2.12 billion. The stock has since pared some gains, and was recently trading up 20.0% at $15.60. The stock's bullish opening occurred on a day that the Renaissance IPO ETF IPO, +1.09% rallied 1.1% in afternoon trading, while the S&P 500 SPX, +0.20% rose 0.2%.