Sanofi has announced positive results from multiple Phase II clinical studies of lunsekimig, an investigational bispecific Nanobody designed to target key drivers of inflammation in chronic respiratory diseases. The therapy met its primary and key secondary endpoints in studies evaluating asthma and chronic rhinosinusitis with nasal polyps (CRSwNP), while also demonstrating an acceptable safety and tolerability profile.

Lunsekimig is a novel pentavalent Nanobody VHH composed of five linked antibody fragments that simultaneously block thymic stromal lymphopoietin (TSLP) and interleukin-13 (IL-13)—two critical pathways involved in airway inflammation and tissue damage. The dual-targeting mechanism is expected to provide enhanced therapeutic benefits in immune-mediated conditions such as asthma.

In the Phase IIb AIRCULES study involving patients with moderate-to-severe asthma, lunsekimig showed a statistically significant reduction in exacerbations and improvement in lung function, measured by pre-bronchodilator forced expiratory volume (FEV1), compared to placebo. The study included adult patients experiencing persistent symptoms despite standard treatment.

Similarly, the Phase IIa DUET study in patients with CRSwNP met its primary endpoint, demonstrating a reduction in nasal polyp size. It also achieved key secondary endpoints, including improvements in nasal congestion and CT scan scores at 24 weeks.

However, results from the exploratory Phase IIb VELVET study in atopic dermatitis were mixed. While the study did not meet its primary endpoint of improvement in eczema severity scores, patients showed progress in secondary measures related to skin clearance.

Across all studies, lunsekimig was generally well tolerated. The most commonly reported adverse events included mild infections such as nasopharyngitis and upper respiratory tract infections, along with injection site reactions. Rates of serious adverse events were comparable between the treatment and placebo groups.

Commenting on the findings, Houman Ashrafian, Executive Vice President and Head of Research and Development at Sanofi, said the results reinforce the potential of lunsekimig’s dual-action mechanism to address multiple aspects of respiratory disease management.

Lunsekimig is currently advancing through further clinical development, including ongoing Phase II and Phase III trials. However, its safety and efficacy have not yet been evaluated by regulatory authorities.

Asthma remains one of the most prevalent chronic diseases globally, affecting an estimated 262 million people, with over half of patients still lacking adequate disease control. Similarly, CRSwNP continues to impact quality of life significantly, often coexisting with asthma.

With these latest findings, Sanofi aims to strengthen its pipeline of innovative therapies targeting immune-driven diseases and address persistent unmet needs in respiratory care.