Pharmaceutical firms have strived to make latecomer drugs to beat Dupixent (dupilumab), the first biologic therapy to win approval for asthma and atopic dermatitis, but their efforts seem to have failed to achieve meaningful progress, experts said.
The latest results of a trial on an interleukin 33 (IL-33) monoclonal antibody (Mab), a possible successor to Dupisent, showed not much progress.
Regeneron and Sanofi recently announced the results of the phase-2 study on IL-33 Mab REGN3500.
The two are conducting the trial to treat asthma, chronic obstructive pulmonary disease, and atopic dermatitis. The latest disclosure was about the results of the asthma treatment.
Regeneron said that the monotherapy of REGN3500 met the primary endpoint of improvement in loss of asthma control when comparing it to placebo. The trial also met a key secondary endpoint, demonstrating REGN3500 monotherapy significantly improved lung function compared to placebo, it said.
However, pharmaceutical sources questioned whether it would be worth developing REGN3500 further.
Although the investigational drug showed improvement compared to placebo, it did not show meaningful progress when it was combined with Dupixent, versus Dupixent monotherapy, they said.
The trial was on 296 moderate-to-severe asthma patients whose symptoms were not controlled well with inhaled corticosteroid (ICS) or long-acting beta-agonist (LABA) therapy for 12 weeks. The patients were divided into four groups – REGN3500 with placebo, REGN3500 with Dupixent, Dupixent with placebo, and placebo.
All patients received fluticasone/salmeterol as the ICS/LABA maintenance therapy, which was withdrawn during the study. At four weeks post-randomization, the LABA was discontinued, and between six and nine weeks the ICS was cut. Patients continued without ICS/LABA maintenance therapy until 12 weeks.
If a patient had a loss of asthma control (LOAC) during the study, they resumed their prescreening ICS/LABA maintenance therapy and entered the safety follow-up period.
The results showed that Dupixent monotherapy showed better results than REGN3500-treated group in all endpoints. The REGN3500+Dupixent group also failed to yield better results than Dupixent-alone group.
Adverse events occurred in 61.6 percent of patients who received REGN3500 alone, 66.2 percent of those in REGN3500+Dupixent group, 56.8 percent of those who received Dupixent alone, and 64.9 percent of patients who received a placebo.
Regeneron’s somewhat poor clinical results created a negative repercussion for AnaptysBio, which is working on similar drug Etokimab (ANB020). After the announcement of REGN3500 results, AnaptysBio’s shares plunged 15 percent Friday.
AnaptysBio is waiting for the results from a phase-2 trial on Etokimab in atopic dermatitis. Earlier, the ATLAS study on the drug in patients with moderate-to-serious atopic dermatitis reached the primary endpoint in June. The phase-2 trial is expected to be completed by year’s end.