Markets are illiquid ..it does not take much volume on either...

Markets are illiquid ..it does not take much volume on either side of the price to drive price action higher and lower. You may be seeing a combination of profit taking from short term position takers and risk off trades due to recession fears and interest rates rising.
Early stage Biotech shares are a target for both long term investors and active traders....do not sweat the intra-day jitters unless they are accompanied by negative announcements if you are an investor. Traders make money through Volatility, and illiquid markets amplify the impact they have.