HCW Biologics Stock Scores Biggest Gain Since May As Cancer Drug Breakthrough Fuels Blockbuster Hopes

HCW Biologics shares logged their best session in over three months on Monday after the firm revealed progress with a new cancer drug it thinks could be a multi-billion-dollar blockbuster.

The stock jumped 60.8% to $5.55 on Monday, marking its best session since May 13, before adding another 0.5% in after-hours trading.

The Florida-based biotech firm said it has developed an advanced form of pembrolizumab, which is sold by Merck as Keytruda and is considered the world’s top-selling FDA-approved immune checkpoint inhibitor.

Drugs in this class are designed to help the immune system fight cancer, but they often only work for a small percentage of patients, and results are not always long-lasting.

HCW Biologics said its version aims to go a step further: not only releasing the “brake” on the immune system but also activating immune cells and helping them infiltrate solid tumors, such as those seen in pancreatic and ovarian cancer. 

In early lab studies and mouse models, the company states that the therapy demonstrated stronger results than Keytruda alone, at dose levels that were well tolerated.

CEO Hing C. Wong noted that global sales of checkpoint inhibitors topped $40 billion in 2024, underscoring the commercial potential if effectiveness can be improved.

The company also sees potential for its therapy beyond cancer. HCW Biologics said checkpoint inhibitors may help clear “senescent” cells, which are aged cells that no longer divide but drive inflammation, making them a possible tool against age-related diseases.

On Stocktwits, retail sentiment was ‘extremely bullish’ amid a 538% surge in 24-hour message volume, placing it among the most trending stocks on the platform.

One user noted they had already taken profits, saying they made money on $HCWB and estimated early buyers likely gained 20–30%.

Another user praised HCW Biologics’ research, suggesting that since immune checkpoint inhibitors have shown success, improving on them could be the right path forward.

HCW Biologics’ stock has declined 68.9% so far in 2025.

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