from the phase 3 ADvocate1 and ADvocate2 trials.
“We’re focused on the responders,” said Andrew Blauvelt, MD, MBA, as he presented the positive findings at the annual congress of the European Academy of Dermatology and Venereology.
Responders were the 291 people whose atopic dermatitis greatly improved after an initial 16 weeks’ treatment with lebrikizumab in both trials and who were then randomly allocated to receive injections every 2 weeks (Q2W, n = 113) or every 4 weeks (Q4W, n = 118), or to receive placebo injections Q2W (n = 60).
Dr. Andrew Blauvelt
“Very interestingly, for me, the Q4W maintenance dosing was just as good as the Q2W maintenance dosing,” said Dr. Blauvelt, president of Oregon Medical Research Center, Portland.
“Another highlight of these data is that the patients who went on to placebo, about 50% of the patients maintained good responses, despite no treatment from week 16 to week 52,” he added.
Most patients did not require topical steroids, and “there were no surprises here” in terms of the safety profile. Lebrikizumab, a monoclonal antibody, binds to soluble interleukin-13 and blocks IL-13 signaling.
“So, the study really shows that specific targeting of IL-13 with lebrikizumab, either Q2W or Q4W, has high maintenance of efficacy and is reasonably tolerated and safe in adolescents and adults with atopic dermatitis,” Dr. Blauvelt concluded.
“We know now that IL-13 is a critical cytokine in AD [atopic dermatitis] pathogenesis. The unique features of this drug I want to highlight is that it has high binding affinity for IL-13,” he said.
“It has a slow dissociation off rate, meaning it binds IL-13 tightly, very potently, and stays blocking and stays hold of IL-13 in a strong manner,” he added. The drug has a half-life of 25 days.
These features could be very important for long-term dosing of the drug, he argued.
Lebrikizumab phase 3 trials
ADvocate1 and ADvocate2 are two of several phase 3 trials evaluating the efficacy and safety of lebrikizumab for the treatment of atopic dermatitis.
These include the completed ADhere study, in which lebrikizumab was used in combination with topical steroids and showed positive results in skin improvement and relief of pruritus.
The ADore study, an open-label trial in adolescents, is yet to report. The ongoing ADjoin study, a long-term extension study, is actively recruiting.
ADvocate1 and ADvocate2 are two identically designed – multicenter, randomized, double-blind, placebo-controlled, parallel-group – monotherapy trials that initially pitched two dosing regimens of lebrikizumab (250 mg) against placebo with a double loading dose at baseline and week 2 and then one dose every 2 weeks. The pair of trials enrolled a total of 869 adolescents and adults.
After the 16-week induction period, all patients in the lebrikizumab arm who had responded to treatment were rerandomly assigned to receive lebrikizumab 250 mg Q2W or Q4W, or placebo Q2W during a 36-week long-term maintenance treatment period.
This brought the total treatment time to 52 weeks for those whose atopic dermatitis had initially responded to lebrikizumab, explained Blauvelt.
Responders were those who, at 16 weeks, had an Investigator’s Global Assessment score of 0 or 1 (IGA 0/1) with a 2-point improvement or who had a 75% improvement in the Eczema Area and Severity Index score (EASI 75) without the need for rescue medication, compared with baseline values.