Two of Sanofi’s lunsekimig Phase II trials have met their primary endpoints in respiratory disease, while a study in atopic dermatitis failed to show benefit.
The drug showed benefit in moderate-to-severe asthma and chronic rhinosinusitis with nasal polyps (CRSwNP), improving lung function in the Phase IIb and IIa studies.
In the AIRCULES Phase IIb study in asthma (NCT06102005), lunsekimig met its primary and key secondary endpoints, demonstrating a statistically significant and clinically meaningful reduction in exacerbations and improvement in lung function, as measured by pre-bronchodilator forced expiratory volume in one second (pre-BD FEV).
The DUET Phase IIa proof-of-concept study (NCT06454240) of lunsekimig in chronic rhinosinusitis with nasal polyps (CRSwNP) met its primary endpoint of change in nasal polyp score from baseline. The drug also met its key secondary endpoints of change in patient-reported nasal congestion/obstruction score and change in Lund-Mackay Computed Tomography (LMK-CT) score. Both endpoints were compared to placebo after 24 weeks.
The Phase IIb VELVET study (NCT06790121) of lunsekimig in moderate-to-severe atopic dermatitis did not meet its primary endpoint of change from baseline in eczema area severity index (EASI) score. There were, however, improvements in the key secondary endpoints measuring skin clearance, including EASI-75 and vIGA-AD 0/1.
Houman Ashrafian, executive vice president and head of R&D at Sanofi, said: “These data are promising and support our belief that the dual-targeting mechanism of lunsekimig may offer a novel treatment option for patients living with respiratory diseases, including asthma. Importantly, these findings underscore lunsekimig’s potential to address multiple critical aspects of respiratory disease management through its unique mechanism.”
Lunsekimig, a bispecific Nanobody VHH, is made of five linked antibody fragments designed to simultaneously block TSLP and IL-13. Across these studies, lunsekimig was generally well tolerated.
Detailed results from the three studies will be presented at upcoming medical congresses.
Lunsekimig is also being investigated in the Phase II AIRLYMPUS study in high-risk asthma (NCT06676319) and in the Phase III PERSEPHONE and THESEUS studies (NCT07190209; NCT07190222), both in chronic obstructive pulmonary disease (COPD).
Lunsekimig is one of a trio of candidates that Sanofi is developing as successors to flagship anti-inflammatory drug Dupixent (dupilumab), which brought in nearly $18bn 2025.
Another candidate in this trio is the anti-OX40L antibody amlitelimab. The COAST-2 study in AD missed one of the co-primary endpoints; benefit was seen in the SHORE study and the Phase III COAST 1 trial (NCT06130566). Though amlitelimab demonstrated efficacy in this AD trial, the drug failed to best the clinical profile of Dupixent, sending Sanofi’s stock sliding at the time.
Citi analysts are looking to Sanofi for more detailed data on asthma, given that it “is a highly competitive market with multiple biologics approved”. Analysts also said the primary endpoint miss in AD was “disappointing” as they had hoped for the drug to be a more credible counter to emerging AD competition compared to amlitelimab.
