AC Immune Initiates Final Cohort in Ongoing Phase 1b/2 ABATE Trial of Anti-Abeta Active Immunotherapy to Treat Alzheimer's Disease
Rhea-AI Summary
AC Immune (NASDAQ: ACIU) dosed the first patient in Cohort AD4 of the Phase 1b/2 ABATE trial and triggered a $12 million milestone from Takeda. AD4 will enroll 36 patients for 12 months (plus 6-month follow-up) and could expand to ~112 patients. 12-month data from AD1–AD3 are expected in Q2 2026. Under the Takeda agreement, AC Immune received a $100 million upfront payment and is eligible for up to $2.1 billion in further milestones and tiered double-digit royalties on sales.
Positive
- $12M milestone payment triggered by dosing first AD4 patient
- Received $100M upfront payment from Takeda
- Eligible for up to $2.1B in development and commercial milestones
- 12-month data readouts from AD1–AD3 expected in Q2 2026
- AD4 initial cohort expands safety and biomarker dataset to 36 patients
Negative
- Further clinical development rights and funding hinge on Takeda exercising its option
- ABATE remains early-stage (Phase 1b/2); efficacy in delaying AD not yet demonstrated
- Planned AD4 expansion to ~112 patients is conditional, not guaranteed
News Market Reaction – ACIU
In the Apr 30 session, ACIU gained 3.41%, reflecting a moderate positive market reaction. Our momentum scanner triggered 2 alerts that day, indicating moderate trading interest and price volatility.
Data tracked by StockTitan Argus on the day of publication.
Key Figures
Historical Context
| Date | Event | Sentiment | 24h Move | Catalyst |
|---|---|---|---|---|
| Apr 07 | Collaboration amendment | Positive | +15.2% | Lilly Morphomer Tau amendment with CHF 10M upfront and large milestones. |
| Mar 19 | Clinical data update | Positive | -4.5% | First in vivo PET images of TDP‑43 pathology with favorable safety profile. |
| Mar 13 | Earnings and update | Neutral | +0.5% | Full‑year 2025 results with pipeline progress and extended cash runway. |
| Mar 05 | Conference participation | Neutral | -3.9% | Announcement of Parkinson’s symposium and TDP‑43 PET‑tracer presentation. |
| Feb 24 | Trial initiation | Positive | +7.5% | First participant dosed in Phase 1 trial of NLRP3 inhibitor ACI‑19764. |
24h Move is the share-price change in the day after each event; other market factors may also have contributed.
Positive R&D and partnership updates have often aligned with gains, while some clinically positive data have seen short-term price weakness.
Over recent months, AC Immune reported several milestones, including a Lilly Morphomer Tau amendment on Apr 7, 2026 that coincided with a +15.19% move. Earlier, positive TDP‑43 PET Phase 1 data on Mar 19, 2026 saw a -4.53% reaction, showing at least one divergence between upbeat clinical news and stock performance. A Phase 1 NLRP3 trial initiation on Feb 24, 2026 aligned with a +7.51% gain. Today’s ABATE cohort initiation adds another clinical milestone alongside this established partnership‑heavy strategy.
Key Terms
phase 1b/2 medical
active immunotherapy medical
immunogenicity medical
pharmacodynamic medical
randomized, double-blind, placebo-controlled medical
prodromal medical
biomarker medical
royalties financial
AI-generated analysis. How Rhea-AI works. Not financial advice.
AC Immune Initiates Final Cohort in Ongoing Phase 1b/2 ABATE Trial of Anti-Abeta Active Immunotherapy to Treat Alzheimer's Disease
- Treatment of first patient in Cohort AD4 in ABATE trial triggers
$12 million milestone payment - Allows evaluation of potential for precision prevention of neurodegenerative diseases
- Data from ABATE Cohorts AD1, AD2 and AD3 after 12 months treatment expected Q2 2026
Lausanne, Switzerland, April 30, 2026 -- AC Immune SA (NASDAQ: ACIU), a clinical-stage biopharmaceutical company pioneering precision therapeutics for neurodegenerative diseases, today announced it dosed the first patients in Cohort AD4 in the ongoing Phase 1b/2 ABATE trial. As a result, AC Immune will receive a
ABATE is assessing ACI-24 in subjects with prodromal AD and in adults with Down syndrome (DS). AD4 includes subjects with prodromal AD.
Dr. Andrea Pfeifer, CEO of AC Immune SA, said: “This milestone underscores the progress in our Phase 1b/2 ABATE trial of ACI-24. AD4 will build on the encouraging early safety and immunogenicity data to date. It allows further evaluation of the potential of ACI-24 and, more broadly, our precision prevention approach to neurodegenerative diseases, which encompasses a pipeline of active immunotherapies and intracellular-targeted small-molecule therapeutics to intervene at the earliest stages of disease.”
ACI-24 is an anti-Abeta active immunotherapy candidate designed to induce a robust antibody response against the toxic forms of Abeta believed to drive plaque formation and AD progression. By inducing plaque clearance and efficiently inhibiting plaque formation in the brain, ACI-24 has the potential to delay or slow AD progression.
ACI-24 is being investigated in the ongoing ABATE randomized, double-blind, placebo-controlled Phase 1b/2 trial to assess its safety, tolerability, immunogenicity and pharmacodynamic effects. Data so far show that ACI-24 is generally safe and well tolerated, and that it has generated anti-Abeta antibody responses at all tested doses.
Cohorts AD1, AD2 and AD3 enrolled a total of 74 patients who received ACI-24 at escalating dose levels. The 12-month data readouts from Cohorts AD1, AD2 and AD3 are expected later in Q2 2026. Cohort AD4 will include an initial group of 36 patients treated for 12 months, with follow-up of 6 months, significantly expanding the safety and biomarker efficacy data set. A subsequent expansion of the AD4 cohort could potentially see the total number of subjects reach approximately 112 patients.
AC Immune is responsible for conducting the ABATE trial. Following the potential option exercise, Takeda would conduct and fund all further clinical development and be responsible for all global regulatory activities as well as worldwide commercialization.
Under the terms of the agreement with Takeda, AC Immune received an upfront payment of
About ACI-24
This product is AC Immune’s anti-Abeta active immunotherapy candidate. The ABATE randomized, double-blind, placebo-controlled Phase 1b/2 trial of ACI-24 for treatment of Alzheimer’s disease (AD) continues fully blinded (NCT05462106). Enrolled patients are required to have a diagnosis of prodromal AD: MCI due to AD according to the National Institute on Aging Alzheimer’s Association (NIA-AA) criteria, and a PET scan at screening must be consistent with the presence of amyloid pathology. Patients will be randomized to one of several doses of ACI-24 or placebo. Following multiple data safety monitoring board (DSMB) reviews, no safety concerns have been raised to date, consistent with previous results. Very encouraging immunogenicity has been shown with clear evidence of anti-Abeta antibody responses against toxic Abeta species observed in the blinded data.
About AC Immune SA
AC Immune SA is a clinical-stage biopharmaceutical company and a global leader in precision prevention for neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, and NeuroOrphan indications driven by misfolded proteins. The Company’s two clinically validated technology platforms, SupraAntigen® and Morphomer®, fuel its pipeline of first- and best-in-class assets, which currently features a range of therapeutic and diagnostic programs, including candidates in Phase 2 and Phase 3 development. AC Immune has a strong track record of securing strategic partnerships with leading global pharmaceutical companies, resulting in substantial non-dilutive funding to advance its proprietary programs and >
SupraAntigen® is a registered trademark of AC Immune SA in the following territories: AU, EU, CH, GB, JP, RU, SG and USA. Morphomer® is a registered trademark of AC Immune SA in CA, CN, CH, EU, GB, JP, KR, NO, RU and SG.
The information on our website and any other websites referenced herein is expressly not incorporated by reference into, and does not constitute a part of, this press release.
For further information, please contact:
| SVP, Investor Relations & Corporate Communications Gary Waanders, Ph.D., MBA AC Immune Phone: +41 21 345 91 91 Email: gary.waanders@acimmune.com | |
| International Media Chris Maggos Cohesion Bureau Phone: +41 79 367 6254 Email: chris.maggos@cohesionbureau.com |
Forward looking statements
This press release contains statements that constitute “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Forward-looking statements are statements other than historical fact and may include statements that address future operating, financial or business performance or AC Immune’s strategies or expectations. In some cases, you can identify these statements by forward-looking words such as “may,” “might,” “will,” “should,” “expects,” “plans,” “anticipates,” “believes,” “estimates,” “predicts,” “projects,” “potential,” “outlook” or “continue,” and other comparable terminology. Forward-looking statements are based on management’s current expectations and beliefs and involve significant risks and uncertainties that could cause actual results, developments and business decisions to differ materially from those contemplated by these statements. These risks and uncertainties include those described under the captions “Item 3. Key Information – Risk Factors” and “Item 5. Operating and Financial Review and Prospects” in AC Immune’s Annual Report on Form 20-F and other filings with the Securities and Exchange Commission. Forward-looking statements speak only as of the date they are made, and AC Immune does not undertake any obligation to update them in light of new information, future developments or otherwise, except as may be required under applicable law. All forward-looking statements are qualified in their entirety by this cautionary statement.
Attachment
