Why SELLAS Life Sciences Group (SLS) Stock Is Up Today

By: Quiver PriceTracker

Posted: 4 days, 19 hours ago / Aug. 21, 2026 6:36 p.m. UTC

SLS

SELLAS Life Sciences Group (SLS) is up 15.3% today. Here is some analysis on what might have caused this price movement.

Analysis: The most likely driver appears to be continued momentum after the company’s recent second-quarter update, which kept investors focused on a potentially near-term pivotal Phase 3 readout for GPS in acute myeloid leukemia. This could also be because traders are leaning into the setup for the REGAL trial’s final event threshold while a large short position adds fuel to upside moves.

Details:

On August 11, the company said final analysis for the Phase 3 REGAL trial of galinpepimut-S in AML will occur after the 80th event, reinforcing that a major data catalyst may be getting closer.

The same update said 28 patients had been enrolled in the Phase 2 SLS009 trial in newly diagnosed first-line AML, with topline data still expected in the fourth quarter of 2026.

SELLAS reported $138.3 million in cash and cash equivalents as of June 30, 2026, giving investors more confidence that it can fund operations while awaiting important clinical milestones.

Short-interest data published for late July showed roughly 55 million shares sold short, or about 28% to 30% of the float, which can amplify gains when buying pressure builds.

Sources:

SELLAS Life Sciences investor relations, SEC, MarketBeat

Disclaimer: This price movement analysis was generated with the help of AI. Please double-check the information provided for mistakes.

$SLS Hedge Fund Activity

We have seen 131 institutional investors add shares of $SLS stock to their portfolio, and 61 decrease their positions in their most recent quarter.

Here are some of the largest recent moves:

STATE STREET CORP added 4,600,202 shares (+54.8%) to their portfolio in Q2 2026, for an estimated $67,898,981
ANSON FUNDS MANAGEMENT LP added 4,500,000 shares (+inf%) to their portfolio in Q2 2026, for an estimated $66,420,000
BLACKROCK, INC. added 2,871,892 shares (+23.5%) to their portfolio in Q2 2026, for an estimated $42,389,125
MARSHALL WACE, LLP removed 2,037,162 shares (-100.0%) from their portfolio in Q2 2026, for an estimated $30,068,511
SUSQUEHANNA INTERNATIONAL GROUP, LLP added 1,653,541 shares (+416.5%) to their portfolio in Q2 2026, for an estimated $24,406,265
BNP PARIBAS FINANCIAL MARKETS added 1,025,006 shares (+2180.1%) to their portfolio in Q2 2026, for an estimated $15,129,088
GEODE CAPITAL MANAGEMENT, LLC added 971,569 shares (+24.8%) to their portfolio in Q2 2026, for an estimated $14,340,358

To track hedge funds' stock portfolios, check out Quiver Quantitative's institutional holdings dashboard. You can access data on hedge funds moves and 13F filings through the Quiver Quantitative API 13F endpoint.

This article is not financial advice. See Quiver Quantitative's disclaimers for more information. Note that there may be inaccuracies due to mistakes in ticker-mapping, and other anomalies.