On October 21, 2025, Alector Therapeutics announced results from their Phase 3 INFRONT-3 clinical trial evaluating latozinemab (AL001) for people with FTD caused by variants in the progranulin (GRN gene). See Alector’s press release here: Alector Announces Topline Results from Latozinemab Phase 3.

Disappointingly, the trial did not reach it’s intended clinical endpoint, changes in a scale that measures FTD symptoms called the Clinical Dementia Rating^® plus National Alzheimer’s Coordinating Center Frontotemporal Lobar Degeneration Sum of Boxes (CDR^® plus NACC FTLD-SB). While latozinemab did result in elevations in progranulin, the treatment did not result in changes in this primary clinical outcome measure, nor other markers of disease progression such as additional biomarkers and imaging data. For more information, see AFTD’s press release here: Alector Announces Results from its Phase 3 Clinical Trial of Potential FTD-GRN Therapeutic | AFTD.

Based on the results, it is expected that the active open label extension and the continuation study will be closed.  People who participated in the trial can expect to hear directly from their trial site and should direct questions to their local site contact.

While it is disappointing when a clinical trial does not meet its intended goals, any trial that finishes recruitment and results in meaningful data, especially in a rare disease like FTD, is a step towards effective treatments. We applaud the people who participated in the trial as well as their families. Volunteering as a research participant is an extraordinary sacrifice, and the only way the science can progress. AFTD is also grateful to the trial investigators and investors who prioritized FTD research.

Luckily, there are many researchers actively investigating other methods of addressing FTD caused by GRN variants, such as through gene therapy. Learn more about other FTD-GRN trials by watching AFTD’s Genetic FTD Clinical Trial Landscape session from the Education Conference and exploring other FTD studies currently enrolling participants. Further, researchers are looking at ways to better understand and intervene in FTD caused by other genes as well as sporadic FTD.

We know many people in the community have questions and concerns about these results. AFTD is working on scheduling a virtual Townhall in the next few weeks to give the community an opportunity to connect and get questions answered. Stay tuned for more information on date and time.

Ways to stay informed:

• Sign up for AFTD’s Science Digest newsletter.
• Enroll in the FTD Disorders Registry to stay informed about new clinical trial opportunities as they emerge.