European biotech company Alvotech S.A. (NASDAQ:ALVO), US-based biopharmaceutical company Kashiv Biosciences LLC and Advanz Pharma, a UK-based pharmaceutical company with a focus on specialty, hospital and rare disease medicines, on Wednesday announced positive topline results from a confirmatory efficacy study of AVT23 (also known as ADL-018), a proposed biosimilar to Xolair (omalizumab).

The randomised, double-blind, multicentre study evaluated AVT23 against Xolair in patients with Chronic Spontaneous Urticaria who did not respond to H1 antihistamines. The trial met its primary endpoint, showing equivalent efficacy and comparable safety between the biosimilar and reference product.

Participants received 150 mg or 300 mg doses subcutaneously every four weeks over 24 weeks. A total of 600 patients took part in the trial, and efficacy and safety were evaluated in 400 patients who received the confirmatory dose of 300 mg. The primary efficacy measure was the change in the weekly Itch Severity Score at Week 12.

Earlier this year, the UK Medicines and Healthcare Products Regulatory Agency accepted the marketing authorisation application for AVT23. Alvotech expects to file with the European Medicines Agency before year-end.

Omalizumab, the active ingredient in Xolair, is used to treat conditions such as allergic asthma, chronic rhinosinusitis with nasal polyps, and IgE-mediated food allergy.

Alvotech and Kashiv Biosciences jointly developed AVT23.