San Diego, California, USA, October 9, 2026
cAMPfield Therapeutics has announced positive Phase 3 clinical trial results for prifemilast, an investigational oral treatment for adults with moderate-to-severe plaque psoriasis. In a head-to-head clinical trial conducted by its development partner, Newsoara Biopharma, prifemilast demonstrated superior efficacy compared with apremilast, an established phosphodiesterase 4 (PDE4) inhibitor. The findings were highlighted at the 26th Annual Fall Clinical Dermatology Conference, held October 8–11, 2026, in Las Vegas, Nevada. The results showed improvements across both primary efficacy endpoints, supporting further investigation of prifemilast as a potential treatment for immune-mediated inflammatory diseases. The company is also advancing the candidate toward clinical evaluation in inflammatory bowel disease (IBD), including ulcerative colitis and Crohn’s disease.
Phase 3 Trial Demonstrates Superior Psoriasis Efficacy
In the head-to-head Phase 3 study, prifemilast 20 mg once daily achieved superior results compared with apremilast 30 mg twice daily at Week 16. The trial randomized 607 participants in a 2:1 ratio to receive either prifemilast or apremilast. The study evaluated two co-primary endpoints: the proportion of patients achieving at least a 75% improvement in the Psoriasis Area and Severity Index (PASI 75) and the proportion achieving clear or almost clear skin according to the static Physician’s Global Assessment (sPGA 0/1). Results showed that 64.6% of patients receiving prifemilast achieved PASI 75, compared with 35.3% receiving apremilast. Additionally, 55.6% of patients in the prifemilast group achieved clear or almost clear skin, compared with 31.3% in the apremilast group. Both comparisons demonstrated statistical superiority, with P values below 0.0001. These findings indicate that prifemilast produced stronger improvements in psoriasis symptoms than the active comparator during the 16-week evaluation period.
Safety Profile and Sustained Treatment Responses
Alongside its efficacy findings, prifemilast demonstrated low rates of serious adverse events and treatment discontinuations in the head-to-head trial. Serious adverse events were reported in 4.0% of patients receiving prifemilast and 2.5% receiving apremilast. Discontinuations due to adverse events were 2.0% and 1.5%, respectively. The company also reported results from a separate placebo-controlled Phase 3 trial in which responses appeared as early as Week 2 and were maintained through Week 52. During the initial 16-week treatment period, discontinuations due to adverse events were similar among participants receiving prifemilast and placebo. Across its clinical development program, more than 1,000 participants have received prifemilast, including more than 250 treated for 52 weeks. This growing clinical safety database will help inform its continued development. However, the reported findings do not establish long-term safety beyond the available follow-up or confirm how the investigational medicine will perform in broader patient populations. Prifemilast has not yet been approved by any regulatory authority, and additional clinical and regulatory evaluation remains necessary.
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cAMPfield Expands Prifemilast Development Into IBD
Beyond psoriasis, cAMPfield Therapeutics is investigating prifemilast for inflammatory bowel diseases, including ulcerative colitis and Crohn’s disease. The candidate is a once-daily, preferential phosphodiesterase 4B (PDE4B) inhibitor designed to target an enzyme associated with inflammatory activity. Its development strategy aims to provide effective oral treatment while limiting inhibition of PDE4D, an enzyme associated with certain dose-limiting adverse effects of PDE4 inhibitors. The company holds exclusive global development and commercialization rights to prifemilast outside Greater China through its licensing agreement with Newsoara Biopharma. Newsoara conducted and sponsored the psoriasis trials in China and plans to pursue regulatory submission for prifemilast in psoriasis in China by the end of 2026. Meanwhile, cAMPfield is preparing global Phase 2 studies in ulcerative colitis and Crohn’s disease. The positive psoriasis results provide an important clinical foundation for these additional investigations, although efficacy in inflammatory bowel disease must be established independently through dedicated trials. The Phase 3 findings strengthen prifemilast’s development prospects, while further research will determine its potential role in treating chronic inflammatory conditions.
Source: cAMPfield Therapeutics press release
