Novartis AG (NYSE: NVS) announced it will acquire Excellergy Inc., a private biotechnology company developing anti-IgE therapies for allergic diseases, for up to $2 billion in upfront and milestone payments.

The acquisition centers on Excellergy's lead asset Exl-111, a half-life extended anti-IgE antibody currently in Phase 1 clinical trials. The drug targets IgE, a protein that drives multiple allergic diseases including food allergies, chronic urticaria, and allergic asthma.

Exl-111 differs from conventional anti-IgE approaches by dissociating receptor-bound IgE, potentially leading to faster suppression of IgE signaling. Preclinical studies and early human pharmacokinetic data from the ongoing Phase 1 trial show sustained drug exposure consistent with its extended half-life design, according to the company.

"Excellergy adds a differentiated next-generation anti-IgE program that builds on biology Novartis knows well, supported by preclinical evidence and early clinical pharmacokinetic data," said Fiona Marshall, President of Biomedical Research at Novartis.

The mechanism could potentially support use across food allergy, chronic spontaneous urticaria, chronic inducible urticaria, allergic asthma and other IgE-mediated diseases, including in pediatric populations, if confirmed in clinical trials.

The transaction is expected to close in the second half of 2026, subject to customary closing conditions including regulatory approvals. The acquisition builds on Novartis' existing presence in allergic disease treatment and IgE biology research.