Check out the companies making the biggest moves midday:

Regional banks —Shares of regional banks plummeted following the collapse of Silicon Valley Bank and Signature Bank. First Republic Bank sank 64%, and Western Alliance Bancorp dropped about 57%. PacWest Bancorp shed 26%. KeyCorp fell nearly 30%, and Zions Bancorporation lost about 24%.

Citi, Bank of America, Goldman Sachs — Shares of major banks also saw losses after the closure of the Silicon Valley Bank and Signature Bank. Citi dropped 6%. Bank of America shed 3%, and Goldman Sachs lost about 2%.

Charles Schwab — The stock sank 10% as part of the broader rout in the banking sector. However, Schwab reassured shareholders and customers that it isn't seeing any significant outflows and that 80% of its total deposits fall within the FDIC insurance limits. Citi also upgraded the stock to buy from neutral, saying the stock's recent decline gives it a "compelling" risk-reward ratio.

Illumina — Shares soared by more than 20% after The Wall Street Journal reported Sunday that billionaire activist Carl Icahn is preparing a proxy fight at the biotech company. He is arguing that the company's acquisition of Grail cost its shareholders about $50 billion.

Moderna — The biotechnology company's shares gained nearly 6% after TD Cowen upgraded the stock to outperform from market perform. The Wall Street firm said Moderna will be a leader in the RSV vaccine market.

Newmont — Shares of the gold miner rallied 5% following a spike in gold prices. Spot gold passed the key level of $1,900 as investors bet the Federal Reserve may tone down rate hikes on the heels of Silicon Valley Bank's collapse.

Eli Lilly — Shares of the drug maker rose about 2.5% after Wells Fargo upgraded the shares to overweight, calling recent weakness a buying opportunity for investors. The firm's analyst said the company has a good research and development engine and an absence of near- to medium-term loss of exclusivity. Wells Fargo also said Eli Lilly isn't dependent on M&A activity for growth

Seagen — Shares surged nearly 16% on news that Pfizer is acquiring the cancer drug maker as it looks past its Covid sales portfolio. Pfizer's stock rose about 1.5% on the news.

Etsy —The stock lost 1%. Over the weekend, NBC News reported that the e-commerce company warned sellers that the collapse of Silicon Valley Bank is causing delays in processing payments. The company said it expects to begin processing the payments as soon as Monday and said the delay will not have a material impact on its quarter.

Provention Bio — Shares surged 258% after Sanofi agreed to acquire Provention Bio for $2.9 billion for its type-1 diabetes treatment, among other immune-mediated disease treatments.

Qualtrics International — Shares of the data analytics firm jumped 6.6% on reports that U.S. private equity group Silver Lake agreed to buy the company for $12.5 billion, or $18.15 per share, alongside Canada's largest pension fund. As part of the acquisition, software group SAP said Monday it will sell its stake in Qualtrics for $7.7 billion.

Insulet — The stock gained 8.5% after news that Insulet will replace SVB Financial Group in the S&P 500 index. SIVB will be removed from the broad market index after the close on Tuesday.

— CNBC's Samantha Subin, Hakyung Kim, Pia Singh and Tanaya Macheel contributed reporting.