ProMIS reports interim PRECISE-AD data showing no ARIA-E, ends Q2 with $53.4 million

ProMIS Neurosciences reported second quarter 2026 financial results and a corporate update on August 13, 2026. The company disclosed interim data from PRECISE-AD, its Phase 1b trial of PMN310 in early Alzheimer's disease patients, which it had first announced on July 28.

PRECISE-AD is a randomized, double-blind, placebo-controlled Phase 1b trial evaluating PMN310 in patients with mild cognitive impairment due to early AD, which completed enrollment in December 2025 with 144 subjects across 22 U.S. sites, randomized 3-to-1 to active drug versus placebo across three dose cohorts of 5, 10, and 20 mg/kg, dosed monthly by intravenous infusion over 12 months.¹ Of the 144 enrolled, 136 were evaluable for the interim analysis, with a population that had a mean age of 73.3 years, was 58% female, and included 61% carrying at least one APOE4 allele, with 11% APOE4 homozygotes.¹

The interim data showed no cases of ARIA-E and a 4.4% incidence of total ARIA, all mild and asymptomatic and consisting only of microhemorrhages, with no treatment-related serious adverse events and no drug-related discontinuations.¹ On biomarkers, the company reported blinded, pooled declines in plasma pTau217 of about 15% from baseline through Day 169 in roughly 68.5% of patients, and a CSF MTBR-tau243 decline of about 13.3% in approximately 62.5% of patients, according to the release. The company said both the direction and proportion of favorable responses were broadly consistent with the trial's 75% active-drug allocation.¹

ProMIS expects all patients to finish 12-month dosing by the fourth quarter of 2026, after which it plans to lock the database, run statistical analysis, and report unblinded 12-month topline data, including full safety results, an expanded biomarker panel, and cognitive outcome measures, in the first quarter of 2027.¹

On the pipeline side, the company's PMN267 program targeting misfolded TDP-43 for ALS/FTD has been humanized in a human IgG1 framework and is progressing through IND-enabling studies¹, and its PMN442 program targeting pathogenic alpha-synuclein for Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy has been humanized and is advancing toward IND-enabling studies.¹

On finances, the quarter ended with $53.4 million in cash and short-term investments, which the company said is expected to fund operations through 2027, beyond its anticipated 12-month topline PRECISE-AD readout expected in the first quarter of 2027.¹ The cash increase primarily reflects $70.1 million in net proceeds received in January 2026 from a private placement financing in which certain directors and management participated alongside external investors.¹ Net loss for the quarter was $11.7 million, or $1.28 per share, compared with a net loss of $10.1 million, or $7.26 per share, in the same period of 2025.¹