Syndax Pharmaceuticals stock (US88906L1052): shares edge lower as short interest stays elevated

Syndax Pharmaceuticals traded near $19.57 on 05/28/2026 on Nasdaq, while MarketBeat showed short interest of 21.71 million shares as of 05/15/2026. The stock remains an active US-listed name with a large short position and a negative P/E ratio.

Syndax Pharmaceuticals shares traded at $19.57 on 05/28/2026 on Nasdaq, according to Robinhood data, after moving between $19.31 and $19.63 during the session and sitting 0.3% below the intraday high. The same-day tape keeps the US-listed oncology name in focus for investors watching Nasdaq biotech names, while the latest short-interest snapshot points to continued positioning pressure.

MarketBeat reported that as of 05/15/2026, Syndax Pharmaceuticals had 21.71 million shares sold short, equal to 25.55% of the public float, with a short-interest ratio of 10.5 and a 9.05% increase versus the prior report. The stock also changed hands at $19.61 on 05/27/2026, and Robinhood showed a market capitalization of $1.73 billion and a negative P/E ratio of -7.02.

As of: 05/28/2026

By the editorial team - specialized in equity coverage.

At a glance

• Name: Syndax Pharmaceuticals
• Sector/industry: Biotechnology, oncology
• Headquarters/country: Waltham, United States
• Core markets: United States and other regulated pharmaceutical markets
• Key revenue drivers: Product sales from marketed oncology therapies and related commercialization activity
• Home exchange/listing venue: Nasdaq (SNDX)
• Trading currency: USD

Syndax Pharmaceuticals: core business model

Syndax Pharmaceuticals develops and commercializes oncology therapies, with its equity story tied to execution in blood-cancer and cancer-care markets rather than broad pharmaceutical diversification.

Industry trends and competitive position

On the current tape, the most visible market signal is positioning rather than a fresh corporate event, with short interest at 25.55% of the public float as of 05/15/2026 and a short-interest ratio of 10.5, according to MarketBeat. That combination can keep a stock sensitive to financing, launch, and clinical-update headlines even when there is no immediate company filing.

For a US-listed biotech name, that matters because Nasdaq investors tend to react quickly to changes in sentiment, and Syndax's trading range on 05/28/2026 was narrow relative to the elevated short base. The stock's negative P/E ratio of -7.02 underscores that the market is still valuing the company on expectations for future earnings power rather than on trailing profitability.

One day earlier, on 05/27/2026, the shares traded at $19.61 and were shown by Robinhood as trading 0.5% above the prior day's level, which is a reminder that the stock can move modestly even without a major headline. That makes the short-interest data a useful context point for readers following the Nasdaq listing from a US-market angle.

Additional news and developments on the stock can be explored via the linked overview pages.

Conclusion

Syndax Pharmaceuticals enters the session with no fresh corporate filing in the provided sources, but the Nasdaq-listed name remains active because of elevated short interest and a valuation profile still centered on future execution. For readers tracking the stock from a US-market perspective, the key question is whether trading around $19.57 can hold up against that positioning backdrop.

The short-interest update adds context to today's move and fits the broader picture of a biotech stock whose market reaction can be driven as much by sentiment as by fundamental disclosures.

Disclaimer: This article does not constitute investment advice. The comprehensive scope of this informative article was made possible through the use of a.i.. Stocks are volatile financial instruments.