Oct 26, 2026 earnings call — Sabirnetug Phase II readout and EBD program
Company expects to announce Phase II ALTITUDE-AD results in November, covering 18-month iADRS primary endpoint and two sabirnetug doses.
EPS $-0.35 (est $-0.39)
Key quotes
"So, today, I'm pleased to confirm that we expect to announce these Phase II results this November."
"ACU-401, in particular, achieved up to a 40-fold greater frontal cortex exposure in nonhuman primates and significant increase in exposures in deep brain regions."
"We ended the third quarter with approximately $79 million in cash and marketable securities on our balance sheet, which is expected to support our current clinical and operational activities into early 2027."
Analyst Q&A 6
Use after plaque clearing
Q (Jason Zemansky · BofA): The analyst asked if sabirnetug could be used as maintenance after plaque clearance or combined with a plaque clearer. He also asked whether ALTITUDE-AD data could inform that use.
A: Management said they favor chronic dosing while patients are in early AD because soluble aggregates persist and drive disease. They agree it would be logical to consider sabirnetug as a post-plaque follow-on, but their primary focus is the ALTITUDE-AD 18-month primary outcome as the first evidence.
"So, we've always been advocates for chronic dosing, essentially while patients are stable within an early AD stage of disease as we believe these soluble aggregates are present and persistent in driving disease pathology." — Daniel O'Connell (CEO)
Dose selection and differences
Q (Jo Yi Chudy · Stifel): They asked why the two doses were chosen and what efficacy or safety differences to expect between them. They wanted to know what to look for in the upcoming readout.
A: Management said Phase II uses IV dosing every 4 weeks at 35 mg/kg and 50 mg/kg. Those doses were chosen based on Phase I exposure, pharmacodynamic effects, and dose modeling; both are thought to be within an efficacious zone, and the 50 mg/kg dose might show more amyloid PET effect.
"So, for the Phase II, we chose doses of 35 mg/kg and 50 mg/kg, and this is IV dosing every 4 weeks." — Daniel O'Connell (CEO)
Success threshold and OLE timing
Q (Pete Stavropoulos · Cantor Fitzgerald): They asked what minimum clinical and biomarker results would justify moving forward, and whether any OLE data will be in the readout. They also asked about the path forward for ACU-301/401 early brain disease (EBD) studies.
A: Management said they guided to a clear clinical success of 30% slowing on the iADRS after 18 months as the zone to move forward. They expect low double-digit ARIA-E and will include primary and secondary efficacy, safety, and biomarker data (imaging and fluid such as p-tau217) in the top line; the 12-month OLE has had >95% rollover and will read out into 2027 and likely not be in the top-line. On ACU-301/401, they said the EBD program has optionality, both candidates give diversity, and ALTITUDE results will inform dosing and biomarker strategy for those early programs.
"So, as you may recall, we've been guiding towards a clear clinical success of 30% slowing on the iADRS after 18 months of placebo-controlled period." — Daniel O'Connell (CEO)
Catching early drug effects
Q (Thomas Shrader · BTIG): They asked how the company is set up to detect earlier symptomatic or biomarker effects, and whether a faster effect could shorten a future Phase III.
A: Management said sabirnetug's selectivity for toxic oligomers raises the possibility of earlier symptomatic or biomarker effects. They said their plans include elements to observe or capture that possibility and that ALTITUDE's readout will tell them whether earlier time points show a drug effect.
"I do know that our plans have incorporated elements of observing or essentially capturing that possibility." — Daniel O'Connell (CEO)
KOL feedback and physician views
Q (Mary McKeown · Citi): They asked what KOLs are saying about sabirnetug and ALTITUDE-AD, what physicians want in a treatment, and feedback on the mechanism.
A: Management said KOLs are focused on better treatment options for patients and are interested in a different mechanism that targets soluble toxic species rather than plaque. They said KOLs are keenly watching ALTITUDE and see the study as potentially shifting thinking about primary treatment approaches.
"In our travels and interactions with KOLs, I mean, they're mostly principally focused on better treatment options for patients." — Daniel O'Connell (CEO)
Patient retention and subcutaneous plans
Q (Dev Prasad · Lucid): They asked about patient retention and how missing data or discontinuations will affect the primary efficacy analysis. They also asked whether subcutaneous work will start after Phase II.
A: Management said retention in the primary ALTITUDE-AD study exceeded expectations and rollover into the OLE has been high, but the data remain blinded. They said missing data will be handled conventionally per protocol, and that a healthy volunteer subcutaneous bioavailability study read out in early '25; they anticipate incorporating a subcutaneous option into Phase III or an extension.
"We anticipate using the Phase III in one direction or another to incorporate a subcutaneous advancement." — Daniel O'Connell (CEO)