Cenna Biosciences' amyloid beta-targeting peptide 8M2D enters Phase I/b trial for early Alzheimer's disease

Cenna Biosciences is moving its synthetic peptide 8M2D — also referred to as Nubytide in prior company disclosures and as P8 in earlier academic literature — into its first human study, with the [NCT07568041 clinical trial](https://clinicaltrials.gov/study/NCT07568041) registered in April 2026 and a start date of September 2026. The La Jolla, California-based company is testing the subcutaneously administered compound in healthy volunteers and people with early Alzheimer's disease, targeting amyloid beta production through a non-enzymatic mechanism that the company describes as potential first-in-class. The asset originates from [UCSD ](https://app.allsci.com/organization/ASC-OH-0000000779324-1.0-1772559499)Alzheimer's research conducted by [Nazneen Dewji, PhD,](https://app.allsci.com/researcher/ASC-PR-8965155633440-1.0-1765457341) who serves as both founder of Cenna Biosciences and principal investigator on the trial. The [Phase Ia/b study](https://app.allsci.com/clinical-trial/ASC-CT-0000001171013-1.0-1777987475) enrolls approximately 54 participants across three sequential parts. Parts I and II are randomized, double-blind, and placebo-controlled, evaluating single ascending doses (up to five dose levels, 30 healthy adults aged 18–55) and multiple ascending doses (up to three dose levels, 18 healthy adults) of 8M2D delivered by subcutaneous injection. Part III is an open-label cohort of approximately six participants with early Alzheimer's disease, aged 55–80, diagnosed with mild cognitive impairment of probable Alzheimer's disease, and carry a qualifying amyloid burden. Primary endpoints across the Phase 1a/b trial assess safety and tolerability alongside pharmacokinetic parameters. In the Alzheimer's disease cohort, the trial also measures changes in plasma and CSF biomarkers including Aβ42, Aβ40, P-tau217, and NP-tau217 from baseline after 14 days of dosing. Primary completion is expected by September 2027, with full study completion in December 2027. The mechanistic rationale for 8M2D rests on a body of preclinical work arising from [UCSD Alzheimer's research](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0122451) published by Dewji and colleagues. The compound belongs to a class of synthetic peptides derived from a fragment of Presenilin-1, a catalytic subunit of the γ-secretase complex. Rather than inhibiting γ-secretase or β-secretase directly — the approach taken by earlier small-molecule secretase inhibitors, several of which failed in late-stage trials due to toxicity or lack of efficacy — 8M2D appears to bind the ectodomain of the amyloid precursor protein (APP) itself, blocking the APP–Presenilin interaction that initiates amyloidogenic cleavage. Preclinical data cited by the NIA described 50%–80% inhibition of Aβ production in cell-based assays and AD mouse models, with additional reductions in total tau, phosphorylated tau, and inflammatory markers in iPSC-derived neurons. Cenna Biosciences has stated that the peptide is not expected to produce amyloid-related imaging abnormalities (ARIA), the cerebral edema and microhemorrhage signal associated with approved anti-amyloid antibodies, because the mechanism does not involve immune-mediated plaque clearance. The technology is exclusively licensed from UC San Diego, where the foundational patents were filed, and Cenna received a USD 2.7 million NIH NIA Phase II SBIR grant in September 2024 to support the path to clinical entry. The competitive landscape for Alzheimer's treatment now includes two approved anti-amyloid monoclonal antibodies — Leqembi (lecanemab; Eisai/Biogen, approved) and Kisunla (donanemab; Eli Lilly, approved) — both of which reduce amyloid plaque burden and have demonstrated modest slowing of clinical decline in early symptomatic populations, at the cost of ARIA in a meaningful proportion of patients. The 8M2D Alzheimer's disease program is mechanistically distinct from both: where approved antibodies clear aggregated Aβ from existing plaques through Fc-mediated microglial phagocytosis, 8M2D is designed to suppress Aβ generation at the production step, upstream of aggregation. Whether suppressing Aβ production in patients who already carry amyloid burden will translate into measurable clinical benefit will not be addressed in this Phase 1a/b trial: the Part III cohort of six patients is sized for pharmacodynamic signal detection, not efficacy. A more directly comparable upstream approach is being pursued by Vigil Neuroscience and others targeting neuroinflammatory pathways, though no peptide-based APP-binding compound appears to have reached clinical evaluation previously, supporting Cenna's potential first-in-class characterization. *** This article was generated with AI assistance and reviewed and edited by the AllSci editorial team Explore more at AllSci News: [https://allsci.com/news/](https://allsci.com/news/) --- Spot something wrong? [Report an issue with this article](https://newsgen-prod.reframedata.com/feedback/alzheimers-disease-clinical-trial-cenna)