North Brunswick, N.J. – October 30, 2026 -- All five antibody-deficient mice treated with Lactiga's LCTG-001 survived influenza infection, compared with two of five in the control group, according to a peer-reviewed preclinical study conducted by McMaster University scientists in collaboration with Lactiga US, Inc.
The research was published in Science Advances on October 14, 2026. LCTG-001 is a nasal antibody treatment made from secretory immunoglobulin A (sIgA) purified from donated human breast milk. Lactiga is developing it for patients with common variable immunodeficiency (CVID) who keep getting respiratory infections despite existing therapies.
Treated mice lost 7.7% of peak weight versus 22.8% in controls
Among antibody-deficient mice, peak weight loss averaged about 7.7% in treated animals and 22.8% in controls. Treated mice also showed less influenza-related illness and lung damage. Protective effects appeared in mice with normal immune systems too.
LCTG-001 reduced lung inflammation and preserved lung tissue even when viral levels later in the infection were comparable between treated and control animals. The company says this points to several protective mechanisms for secretory IgA, including limiting virus-associated tissue damage. The product was given through the nose before and after influenza exposure.
Milk pooled from 120 donors neutralized RSV, adenovirus and two influenza A strains
Researchers pooled milk from 120 donors to build a diverse antibody population. In the study, LCTG-001 neutralized respiratory syncytial virus (RSV), human adenovirus type 5, and influenza A strains H1N1 and H3N2. It also recognized highly pathogenic avian influenza A (H5N1).
Chief Scientific Officer Viraj Mane, a study co-author, said the data show activity through both neutralizing and non-neutralizing mechanisms. He said this supports further development of polyclonal sIgA as a broad-acting, mucosally delivered antibody treatment.
FDA orphan and rare pediatric designations back CVID program
Conventional immunoglobulin replacement helps CVID patients fight infections but does not restore the secretory IgA that protects the nasal passages. LCTG-001 targets that gap through nasal antibody replacement.
The U.S. Food and Drug Administration has granted LCTG-001 both Orphan Drug and Rare Pediatric Disease designations for CVID. Lactiga is advancing toward first-in-human clinical studies. Its pipeline also includes LCTG-003, an oral sIgA treatment in development for inflammatory bowel disease.