PARIS – Dupilumab scorched its way through a landmark pivotal phase 3 clinical trial in adolescents with moderate to severe atopic dermatitis (AD), achieving unprecedented clinically meaningful improvements in signs and symptoms of the disease along with important quality of life benefits, Eric L. Simpson, MD, reported at the annual congress of the European Academy of Dermatology and Venereology.
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Dr. Eric L. Simpson
Indeed, akin to that previously shown in adults with moderate to severe AD in phase 3 trials that earned the biologic U.S. and European regulatory approval in the adult population, noted Dr. Simpson, professor of dermatology at Oregon Health & Science University, Portland.
This positive phase 3 study represents a major development in pediatric dermatology because of the pressing unmet need for better treatments for teens with moderate to severe AD whose disease can’t be controlled with topical therapies. The adolescent years are, after all, a critical period in growth and development, and a debilitating, uncontrolled disease can reshape that experience in unwelcome ways.
“Atopic dermatitis profoundly affects quality of life in adolescents and their family: The itching affects mood and sleep, these patients commonly have anxiety and depression, and the chronic and relapsing nature of the disease adversely affects the family,” the dermatologist observed.
Currently, no systemic agent is approved for pediatric patients with AD because evidence demonstrating a favorable benefit-to-risk profile has been lacking. The dupilumab study was the first-ever phase 3 trial of a biologic in such a population.
The phase 3 adolescent trial was a 16-week, randomized, double-blind, multicenter, placebo-controlled study of 251 patients aged 12-17 years with moderate to severe AD, which could not be adequately controlled with topical therapies. Participants averaged 14 years of age, with a 12-year history of AD. “These patients had the disease basically their whole life,” Dr. Simpson noted.
They were more severely affected than participants in the adult clinical trials, with mean Eczema Area And Severity Index (EASI) scores in the mid-30s and an average 56% involved body surface area. The adolescent AD patients had a heavy burden of comorbid allergic type 2 immune comorbidity: Fully 92% of them had documented asthma, food allergy, allergic rhinitis, and/or some other form of allergic comorbidity. The majority of the teens were categorized as having severe AD, whereas most participants in the adult phase 3 trials of dupilumab had moderate disease. That distinction becomes relevant in comparing the trial results.
Participants were randomized to once-monthly subcutaneous injections of dupilumab at 300 mg, following a 600-mg loading dose, or to an injection of 200 mg or 300 mg every 2 weeks with an initial dose of 400 mg or 600 mg based upon a body weight cutoff of 60 kg, or to biweekly placebo injections.
The coprimary endpoints were the proportion of patients who achieved an EASI 75 response at week 16 and achievement of an Investigator’s Global Assessment (IGA) score of 0 or 1, meaning clear or almost clear, on a 5-point scale at week 16.
This trial introduced an important new design feature that physicians can expect to see more of in the future: regulatory agencies now want to see the effects of monotherapy in pivotal studies in AD. Previously, participants in AD studies of systemic agents could also utilize topical steroids as needed. No longer. In the adolescent dupilumab study, resort to rescue topical steroids led to exclusion from inclusion in the primary outcome results. Not surprisingly, this lack of access to rescue medication resulted in a 60% dropout rate by 16 weeks in placebo-treated controls, a 30% dropout rate in teens on dupilumab every 4 weeks, and a 20% dropout rate with biweekly dupilumab.
The EASI 75 rate at week 16 was 8.2% with placebo, 38.1% with monthly dupilumab, and 41.5% with biweekly dosing. The other coprimary endpoint – an IGA of 0 or 1 at 16 weeks – was achieved in 2.4% of controls, 17.9% with dupilumab at 300 mg every 4 weeks, and 41.5% with biweekly dosing.
Turning to secondary endpoints, Dr. Simpson reported that baseline peak pruritus Numeric Rating Scale scores dropped by 19% with placebo at 16 weeks, compared with reductions of 45.5% and 47.9% with monthly and biweekly dupilumab, respectively.
An EASI 50 response,while not as impressive as an EASI 75, is nonetheless considered clinically meaningful improvement. It was attained in 12.9% on placebo and 54.8% and 61% on monthly and biweekly dupilumab.
From a mean baseline score of 13.6 on the Children’s Dermatology Life Quality Index, scores improved over the course of 16 weeks by a mean of 5.1 points with placebo, 8.5 points with monthly dupilumab, and 8.8 points with biweekly biologic therapy. The same pattern was noted with regard to the Patient-Oriented Eczema Measure or POEM.
Adverse events mirrored those documented in the pivotal trials in adults: increased rates of mild to moderate conjunctivitis: 4.7% with placebo, 10.8% with monthly dupilumab, and 9.8% with biweekly dupilumab, along with single-digit rates of injection-site reactions. As in adult AD patients, however, these side effects were counterbalanced by significantly reduced rates of skin infections in the adolescent group: 20% during 16 weeks with placebo, and 13.3% and 11% with monthly and biweekly biologic therapy, respectively.
Study participants had a mean baseline score of 12.5 on the Hospital Anxiety and Depression Scale, which is categorized as clinically significant psychiatric disease. The impact of dupilumab therapy on those scores will be the topic of a future presentation, Dr. Simpson said.
Across the board, specific outcomes were consistently numerically better in patients who received dupilumab biweekly than monthly, albeit not statistically significantly so. Dr. Simpson thinks he knows why: Lab studies showed that the mean serum concentration of functional dupilumab in patients who got the biologic biweekly was nearly twice that for the group with monthly dosing.
At first glance, the IGA “clear” or “almost clear” response rates seen with dupilumab in the adolescent study appeared to be less robust than in the adult pivotal phase 3 trials, such as the SOLO 1 and SOLO 2 trials (N Engl J Med. 2016 Dec 15;375[24]:2335-48), also led by Dr. Simpson.
“I think that’s because of the greater severity of that baseline adolescent population,” he commented. “It made for a much lower placebo response rate. But when you correct for the placebo-subtracted difference, the rates are actually pretty similar, and a lot of the other endpoints are the same or even better than in SOLO.”
After his presentation, Dr. Simpson commented, “This is huge. This is the study we’ve been waiting for.”
Elsewhere at the EADV congress, Emma Guttman-Yassky, MD, PhD, deemed the pivotal phase 3 trial in adolescent AD patients one of the meeting’s highlights. And it’s a harbinger of more good things to come, because the investigational drug pipeline for AD is full of promising candidates addressing the disease from a variety of novel directions. The long therapeutic drought in AD appears to have finally ended, observed Dr. Guttman-Yassky, professor and vice-chair of the department of dermatology at Icahn School of Medicine at Mount Sinai, New York.
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Dr. Emma Guttman-Yassky
That’s welcome news because AD is the most common inflammatory skin disease, both in adults, where the latest data puts the prevalence at 7%-10%, and in children, where the global rate is 15%-25%.
And while at the EADV congress only the 16-week data were reported in the new adolescent study, there is reason to be optimistic that the benefits will remain durable over time. Dr. Guttman-Yassky cited the published 52-week data from the large phase 3 CHRONOS trial in adults with moderate to severe AD. In that trial, in which patients could use concomitant topical steroids, the EASI 75 rates at week 16 were 69% in patients on dupilumab at 300 mg every 2 weeks, 64% with 300 mg weekly, and 23% with placebo. Reassuringly, at 52 weeks the EASI 75 response rates were essentially unchanged: 65%, 64%, and 22% (Lancet. 2017 Jun 10;389[10086]:2287-303).
“This is what we are seeking: not just treatment that is able to quickly modify disease, but we want the treatment to be sustained, and of course we want it to be safe for our patients because we know we cannot use cyclosporine for a long time,” Dr. Guttman-Yassky said.
Dr. Simpson reported serving as a consultant to and recipient of research grants from Sanofi and Regeneron, which sponsored the adolescent study, as well as more than a dozen other pharmaceutical companies. Dr. Guttman-Yassky reported serving as an advisor and consultant, and has received grants/research funding from Regeneron, and multiple other companies.