Company: PRTA
Filing Date: 2025-08-04
Form Type: 10-Q
Source: 0001559053-25-000031
Chunk: 32

Company: PROTHENA CORP PUBLIC LTD CO
Filing Date: 2025-08-04
Form: 10-Q
Item: Part I, Item 2
Chunk 32
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 participants received a single dose of BMS-986446 or placebo intravenously (“ IV”) and were followed for up to two months. The results of the trial found all three dose level cohorts of BMS-986446 to be generally safe and well tolerated, meeting the Phase 1 SAD trial primary objective. None of the treatment emergent adverse events (“ TEAE”) were serious. No clinically relevant changes were observed in other safety parameters. BMS-986446 also met key pharmacokinetic (“ PK”) and immunogenicity secondary endpoints. Plasma drug concentrations of BMS-986446 increased in a dose-proportional manner. Furthermore, BMS-986446 exposure in cerebrospinal fluid (“ CSF”) was measured in the high dose cohort and based on the robust exposure of BMS-986446 in the CSF (day 29 CSF:Plasma ratio=0.2%), substantial target engagement is expected in the CNS. BMS-986446 had a desirable immunogenicity profile with no persistent BMS-986446-induced antidrug antibodies (“ ADA”s) observed.

A multiple ascending dose (MAD) portion of the Phase 1 clinical trial was ongoing at the time BMS acquired the global rights to the program and control of the Phase 1 trial. All program updates going forward, including results from ongoing and any future BMS-986446 clinical trials, will be reported by BMS.

In the second quarter of 2025, BMS initiated a Phase 1 clinical trial to assess drug levels, tolerability and absolute biological availability of single subcutaneous dose of BMS-986446 in healthy participants. This is a Phase 1, randomized, open-label, parallel, single-dose clinical trial to assess the pharmacokinetics, tolerability, and absolute bioavailability of subcutaneous administration of BMS-986446, an anti-MTBR tau monoclonal antibody, in approximately 46 healthy participants.

Phase 2 Clinical Trial

In the first quarter of 2024, BMS advanced the anti-tau program BMS-986446 with the initiation of a Phase 2 clinical trial (NCT06268886). This is a randomized, double-blind, placebo-controlled, global, Phase 2 clinical trial designed to evaluate the efficacy, safety, and tolerability of BMS-986446, an anti-MTBR tau monoclonal antibody, in approximately 310 participants with early Alzheimer's disease. Participants will be randomized into one of three treatment