Sanofi's 'daughter of Dupixent' heads to phase 3 in asthma

A drug billed by Sanofi as a successor to its blockbuster inflammation and immunology blockbuster Dupixent is being prepared for phase 3 trials in asthma – even though it missed the mark in a midstage trial.

In an update on its respiratory pipeline this morning, Sanofi said that anti-OX40L antibody amlitelimab failed to meet its primary endpoint in the phase 2 TIDE-Asthma study, involving patients with heterogeneous, inflammatory forms of the respiratory disorder, at the highest dose level.

There was "nominal significance" at the medium and low doses – a statistical term that generally means the finding may not be clinically or practically significant – but, nevertheless, the company believes that the drug could represent "a breakthrough for this underserved patient population if observed in later studies."

IL-4 and IL-13 inhibitor Dupixent (dupilumab) is currently approved as an add-on treatment for moderate-to-severe asthma characterised by an eosinophilic phenotype – a specific form of inflammation – and Sanofi is hoping amlitelimab could be suitable for broader use.

The drug has also shown efficacy in a phase 2b atopic dermatitis study – another of Dupixent's long list of approved indications – and is one of the pipeline projects held up by Sanofi as having blockbuster sales potential.

In the TIDE-Asthma trial, amlitelimab was able to achieve a "clinically meaningful" reduction in asthma exacerbations at the medium dose tested, and a numerically greater reduction at the high dose, at week 60. The effect of the drug was stronger in patients with elevated levels of eosinophils and neutrophils, two classes of white blood cell.

Eosinophils tend to be high in patients whose asthma is characterised by high immunoglobulin E, hyper-reactive airways, and poor lung function, while elevated neutrophils seem to be a factor in exacerbation rates.

In these patients, there was a 70% reduction in asthma exacerbations, as well as improved lung function and asthma control at week 60 in the trial.

"These results demonstrate that amlitelimab has potential to improve key disease outcomes in asthma patients with continued unmet need," said Sanofi, which added that the phase 3 programme in asthma is "currently being planned."

The company is already running four phase 3 trials of amlitelimab in atopic dermatitis and has said it hopes to file for approval in that indication in 2026. Phase 2 trials, meanwhile, are underway in hidradenitis suppurativa (HS), systemic sclerosis, coeliac disease, and alopecia.

Sanofi also said today that it is expanding the development of asthma candidate lunsekimig, a bispecific antibody targeting TSLP and IL-13, and is now running studies in chronic obstructive pulmonary disease (COPD) and chronic rhinosinusitis with nasal polyps (CRSwNP).

Meanwhile, the clinical trial programme for IL-33 inhibitor itepekimab is being expanded into CRSwNP, along with COPD and bronchiectasis. Phase 3 data is expected later this year for COPD, while phase 2 results in bronchiectasis should come in 2026.