Stocks are continuing their rollercoaster pattern midday, as Wall Street attempts to lift itself out of the worst selloff since March 2020.

Biotech stocks came under selling pressure in the final week of 2021, although they carved out modest gains for the year. Here are the key catalysts that can sway biotech stocks in the unfolding week.

The FDA and CDC announced their recommendation to pause the use of Johnson & Johnson's JNJ COVID-19 vaccine following incidences of severe clots. J&J's pain turned into  gains for other COVID-19 vaccine companies.

Conventional wisdom says that insiders and 10% owners really only buy shares of a company for one reason — they believe the stock price will rise and they want to profit from it. Insider buying can be an encouraging signal for potential investors.