The biotech sector is experiencing a pullback after a significant surge the previous day, which was ignited by positive cancer vaccine trial results from Moderna. This "buy the rumor, sell the news" dynamic is leading to profit-taking across the sector. Adding to the negative sentiment, Edesa Biotech's stock fell sharply after the company announced a $25 million public stock offering. The broader market's underlying weakness may also be contributing to the sector's decline as investors rotate out of recent high-flyers.