3 Penny Stocks to Watch Now, 5/21/26

HCW Biologics (HCWB), MetaVia (MTVA), and Silexion Therapeutics (SLXN) are the three penny stocks to watch on May 21, according to TipRanks’ Penny Stock Screener tool.

Penny stocks refer to low-priced shares, typically under $5 apiece, and are usually issued by companies whose market capitalizations hover around $300 million.

The three stocks highlighted in this article were selected for having the largest dollar volumes at the close on Wednesday, May 20. This means that they had the highest overall dollar value of shares traded, calculated by multiplying the number of shares exchanged by the stock’s market price.

• HCW Biologics (HCWB): This is a Florida-based pre-clinical stage biopharma company that develops treatments to boost the body’s immune system’s ability to fight off inflammation and other diseases that come with old age. The company’s lead drug candidate is codenamed HCW9218, which is targeted at treating patients with conditions such as pancreatic, ovarian, and breast cancer. On May 20, HCWB shares surged by more than 129% to $2.43 per share, returning a dollar trading volume of $475.67 million. The company’s shares have been rallying following the release of its Q1 2026 earnings report last Friday.
• MetaVia (MTVA): MetaVia is also an American biopharma company. However, unlike HCW Biologics, it is clinical-stage and focuses on developing treatments for cardiometabolic diseases, that is, conditions that affect the heart and involve problems with how the body breaks down and uses food and nutrients. On May 20, MTVA hit a dollar volume of $179.04 million after its shares jumped by approximately 54% to $2.89 per share. This came after the company announced the publication of a peer-reviewed lab study that showed that its experimental drug vanoglipel can help to reduce liver scarring in MASH, a critical fatty liver disease.
• Silexion Therapeutics (SLXN): This is an Israeli biopharma company focused on developing cancer drugs to treat solid tumors using ribonucleic acid (RNA) interference. This describes the process that uses small RNA molecules in the body to silence disease-causing genes. On May 20, SLXN closed the day with the third-largest trading volume of $173.51 million after its shares jumped by approximately 97% to 53 cents per share. This came after the company released its first-quarter 2026 earnings and provided an update on Israeli government approval for Phase 2/3 clinical trials of its lead drug candidate SIL204 for the treatment of locally-advanced pancreatic cancer.

More About TipRanks’ Penny Stock Screener

Analysts looking to stay up-to-date with penny stocks can rely on TipRanks’ Penny Stock Screener tool, which makes it possible for investors to check out the thousands of penny stocks traded daily in the U.S. using filters such as sector, price target upside, Smart Score, analyst consensus, dollar volume, and price change.