Two years ago, Dermavant forked over GBP150 million ($198 million) upfront to get its hands on GlaxoSmithKline’s phase 3-ready psoriasis cream. Now, with positive phase 3 data in hand, the company is ushering the drug toward an FDA filing in 2021.
The cream, tapinarof, outshone an inactive cream in two identical phase 3 studies that together enrolled more than 1,000 patients. The trials, dubbed PSOARING 1 and PSOARING 2, tested the drug in about 340 patients and the vehicle, or inactive, cream, in about 170 patients. After 12 weeks of using tapinarof daily, 35% of patients in the first trial and 40% in the second achieved clear or almost clear skin as measured by the Physician Global Assessment, a visual assessment of psoriasis graded on a five-point scale. Compare that to only 6% of patients using the vehicle cream in both trials.
Tapinarof also did better than the vehicle cream on the trial’s key secondary endpoint. After 12 weeks, 36% of tapinarof patients in the first trial and 48% in the second trial achieved PASI 75–a 75% reduction in psoriasis area and severity–compared to just 10% and 7% of patients using the vehicle cream.
Side effects were similar to those seen in the phase 2 study of tapinarof. Most of them were mild to moderate and affected the areas where patients were using the drug. The most common effects were folliculitis, or inflammation of hair follicles, rash, and nasopharyngitis, or a cold. Less than 6% of tapinarof patients quit the study because of side effects.
“We believe these data give us a clear pathway to regulatory filing,” Dermavant CEO Todd Zavodnick said in a statement. “Subject to the completion and findings of our ongoing long-term extension study, which is fully enrolled, Dermavant currently expects to file a New Drug Application (NDA) with the U.S. Food and Drug Administration (FDA) for tapinarof topical cream for the treatment of plaque psoriasis in 2021.”
More than 90% of patients in the PSOARING trials continued onto the extension study, which will follow patients for another 40 weeks.
There are multiple drugs on the market to treat psoriasis, a chronic autoimmune disorder where patients have patches of red, inflamed skin covered in scales. But these antibody drugs, including AbbVie’s Humira and Skyrizi, Johnson & Johnson’s Stelara and Novartis’ Cosentyx, must all be injected. And that’s not all–needles aside, the systemic nature of these drugs could also lead to immune system-related side effects.
“The PSOARING 1 and PSOARING 2 results support our belief that, subject to FDA approval, tapinarof cream could become a highly beneficial treatment option for adult patients living with mild, moderate and severe plaque psoriasis,” Dermavant Chief Medical Officer Philip Brown, M.D., said in the statement.
“With minimal systemic drug exposure, these data point to the potential use of tapinarof as a novel topical non-steroidal, capable of being used in sensitive and difficult to treat areas of the body such as face, groin and under arms. As such, we are excited by the efficacy and safety results of tapinarof exhibited across multiple trials,” Brown added.
Dermavant is also developing tapinarof for atopic dermatitis, or eczema. It is developing two more treatments for eczema that have different mechanisms–one is a JAK/Syk inhibitor, while the other is a topical PDE4 inhibitor–and it is also working on programs in acne, vitiligo and primary focal hyperhidrosis, or excessive sweating.