Haverhill Financial Research · News · October 11, 2026
The short version
SELLAS's Phase 3 REGAL trial of galinpepimut-S (GPS) in acute myeloid leukemia reaches its final analysis when the 80th patient dies. The last count SELLAS gave was 78, as of May 11, 2026. In its August 11 update the company said it was "approaching" the 80th event and would announce it when it happens. As of October 11, it has not.
The answer is close, but not here yet. Two more events trigger the final analysis. Topline results follow after a fixed set of steps, which we lay out below.
Rumors have moved the stock. In late August a German outlet reported that the 80th event had occurred. SELLAS has not confirmed it, and the shares rose 15% that day.
A second readout is due this quarter. SELLAS expects topline data from its Phase 2 trial of SLS009 in newly diagnosed AML in Q4 2026.
How we got here
What happens after the 80th event
SELLAS has said it will announce the 80th event when it occurs. That starts a set sequence: the database is locked, the data is reviewed while still blinded, the statistical analysis is run, the trial is unblinded, and topline results are released. We expect topline results within weeks of the announcement, though SELLAS has not given a timeline.
The bar for a win. With only 80 deaths behind the final analysis, GPS needs a large survival benefit to be statistically significant. By our estimate, it needs a hazard ratio of about 0.65 or lower, meaning roughly a third lower risk of death at any point than patients on standard treatment.
What each outcome would mean
Why the long wait cuts both ways
Deaths ran at about one a month through May, then the count stalled. If GPS works, patients on it should be living longer, which would slow the final deaths. But a slow count can also mean both arms enrolled healthier patients than the trial assumed. Because the data is still blinded, nobody outside the trial can tell which it is. Each extra quarter of waiting costs SELLAS about $8 million in cash.
SLS009: the other Q4 readout
SLS009 (tambiciclib) is a pill being tested with azacitidine and venetoclax, the standard regimen for newly diagnosed AML patients who cannot have intensive chemotherapy. As of August, 28 of a planned 80 patients had enrolled. Early, single-arm data like this will not decide the stock, but strong results would add a cushion if REGAL disappoints.
Our take
Nothing in the last two months changes our numbers. We think REGAL has a fair chance of working, but the share price still assumes a near-certain win. Our rating stays Sell with a 12-month price target of $7, a probability-weighted blend of the outcomes above. A clean topline with a hazard ratio of 0.55 or lower, or the price falling below about $5 before the readout, would make us look again.
The full case is in our report: SELLAS Life Sciences (SLS): Haverhill Research Report.
Sources and disclosures
Disclosures. Haverhill Financial Research is a publisher of general financial commentary. This article is not personalized investment advice and does not consider any reader's financial situation; readers should do their own research. Price targets are estimates of value, not guarantees, and clinical-stage biotech stocks can lose most of their value on a single trial result. Scenario values and the statistical threshold are Haverhill estimates from our October 10, 2026 report. The author of this post does not hold a position in SLS. Data as of October 11, 2026.
