Global Blood Therapeutics launched an initial public offering at $20 per share and its stock price more than doubled to $43.11 at the end of its first day of trading on Aug. 12, proving that investors may be concerned about a biotechnology bubble, but they're not overly worried that it will burst soon.
Then again, while the South San Francisco-based sickle cell drug developer grossed $120m from the sale of 6m shares, it...