- In a head-to-head Phase 3 trial, prifemilast nearly doubled the rate of PASI 75 response compared with apremilast and achieved superiority on both co-primary endpoints
- Results support the potential of prifemilast to deliver greater efficacy than apremilast, with low rates of serious adverse events and discontinuations similar to apremilast
- In a second, placebo-controlled Phase 3 trial, prifemilast demonstrated superior efficacy to placebo with responses maintained through 52 weeks
- With more than 1,000 participants dosed, prifemilast has an extensive clinical safety database, including more than 250 participants treated for 52 weeks
- These positive results reinforce the potential of prifemilast to treat immune-mediated inflammatory diseases beyond psoriasis; cAMPfield is advancing prifemilast into global Phase 2 trials in ulcerative colitis and Crohn’s disease
SAN DIEGO, Oct. 9, 2026 /PRNewswire/ — cAMPfield Therapeutics, Inc. (cAMPfield), a clinical-stage biopharmaceutical company developing well-tolerated and highly effective oral medicines for immune-mediated inflammatory diseases, today highlighted data from a head-to-head Phase 3 trial in which prifemilast, its once-daily, preferential PDE4B inhibitor, demonstrated superior efficacy versus apremilast in adults with moderate-to-severe plaque psoriasis. Results from the head-to-head trial, a second Phase 3 trial, and a Phase 2 dose-ranging trial, all sponsored and conducted in China by cAMPfield’s partner, Newsoara Biopharma Co., Ltd. (Newsoara), were presented in two posters at the 2026 Fall Clinical Dermatology Conference in Las Vegas.
In the head-to-head Phase 3 trial, prifemilast 20 mg once daily achieved superiority over apremilast 30 mg twice daily on both co-primary endpoints at Week 16. It nearly doubled the proportion of patients achieving at least a 75% improvement in Psoriasis Area and Severity Index (PASI 75) (64.6% vs. 35.3%) and the proportion of patients achieving clear or almost clear skin (sPGA 0/1, 55.6% vs. 31.3%; both P<0.0001). Rates of serious adverse events (4.0% vs. 2.5%) and discontinuations due to adverse events (2.0% vs. 1.5%) were low and similar between treatment arms.1 In a second, placebo-controlled Phase 3 trial, responses were seen as early as Week 2 and maintained through 52 weeks.2 Discontinuations due to adverse events during the 16-week treatment period were similar with prifemilast and placebo (1.7%–1.8% vs. 1.8%).2
“Outperforming apremilast head-to-head is a high bar, and prifemilast cleared it decisively on both co-primary endpoints, demonstrating its potential to be a best-in-class PDE4 inhibitor,” said Bill Gerhart, Chief Executive Officer at cAMPfield. “We are grateful to Newsoara and to the investigators and patients who made these trials possible, and we look forward to building on these results for patients living with IBD.”
Plaque psoriasis (PsO) and inflammatory bowel disease (IBD) are immune-mediated inflammatory diseases that share overlapping inflammatory pathways, cytokine networks, and genetic risk factors.3 PDE4 inhibition has also shown activity in ulcerative colitis. In a Phase 2 trial in patients with ulcerative colitis, apremilast did not meet its primary endpoint at 40 mg twice daily, but at 30 mg twice daily (the dose used as the comparator in the PsO head-to-head trial), 31.6% of patients achieved clinical remission at Week 12 versus 12.1% on placebo.4 These results, together with clinical experience spanning more than 1,000 trial participants in the United States and China, including more than 250 participants treated for 52 weeks,5 support cAMPfield’s advancement of prifemilast into global Phase 2 trials in ulcerative colitis and Crohn’s disease.
“For more than a decade, the promise of PDE4 inhibition in IBD has been held back by the limitations of earlier-generation molecules,” said Graham Heap, MD, PhD, President, R&D at cAMPfield. “The data presented at the conference suggest that prifemilast has the potential to be a highly effective PDE4 inhibitor, delivering meaningfully greater efficacy than the standard of the class with once-daily dosing. These results give us even greater confidence as we advance prifemilast into global Phase 2 trials in ulcerative colitis and Crohn’s disease.”
About the Prifemilast Psoriasis Clinical Trials
The prifemilast psoriasis program includes three randomized, double-blind, multicenter trials sponsored and conducted in China by Newsoara to evaluate the efficacy, safety and tolerability of prifemilast in adults with moderate-to-severe plaque psoriasis.
The head-to-head Phase 3 trial (NCT07712731) randomized 607 participants 2:1 to prifemilast 20 mg once daily or apremilast 30 mg twice daily for 16 weeks; apremilast was titrated in line with its US prescribing information, while prifemilast required no titration.1,6 The co-primary endpoints were the proportion of patients achieving PASI 75 and sPGA 0/1 at Week 16.
The placebo-controlled Phase 3 trial (NCT07712705) randomized more than 500 participants to prifemilast 10 mg, prifemilast 20 mg, or placebo once daily for 16 weeks, followed by a 36-week extension in which all participants received prifemilast. The Phase 2 dose-ranging trial (NCT07707141) randomized 123 participants to prifemilast 6 mg, 10 mg or 20 mg or placebo once daily for 12 weeks and showed dose-dependent improvements, with 67.7% of patients on 20 mg (n=31) achieving clear or almost clear skin at Week 12 compared with 6.7% on placebo.2 The primary endpoint of both placebo-controlled trials was PASI 75 response.
Poster Presentations
Two posters were presented at the 26th Annual Fall Clinical Dermatology Conference, being held October 8–11, 2026, in Las Vegas, and are available on the cAMPfield website at https://campfieldtx.com. The abstracts and posters are expected to be published in the Dermatology Online Journal.
- Poster 1: Prifemilast, an Oral Phosphodiesterase 4B (PDE4B)-Selective Inhibitor, Demonstrates Rapid and Durable Efficacy With a Favorable Tolerability and Safety Profile in Moderate to Severe Plaque Psoriasis: Results From Phase 2 and 3 Trials
- Poster 2: Superior Efficacy of the Oral Phosphodiesterase 4B (PDE4B)-Selective Inhibitor Prifemilast Versus Apremilast in Moderate to Severe Plaque Psoriasis: Top-Line Results of a Head-to-Head Phase 3 Trial
About Prifemilast
Prifemilast is an investigational, once-daily, preferential PDE4B inhibitor that has been studied in more than 1,000 participants in the United States and China to date, including more than 250 participants treated for 52 weeks.5 Prifemilast targets PDE4B, the isoform most closely associated with anti-inflammatory activity, while minimizing inhibition of PDE4D, an isoform associated with dose-limiting adverse effects. Its structure limits central nervous system penetration and slows absorption, and its extended half-life supports once-daily dosing.7 Prifemilast has demonstrated superior efficacy to apremilast in a head-to-head Phase 3 trial and positive results in a placebo-controlled Phase 3 trial in plaque psoriasis. Across these trials, its safety profile was consistent with the PDE4 inhibitor class, with rates of discontinuation due to adverse events comparable to placebo and similar to apremilast. Prifemilast is an investigational drug and has not been approved by any regulatory authority for any indication.
About Inflammatory Bowel Disease
Inflammatory bowel disease (IBD), which includes ulcerative colitis and Crohn’s disease, is a chronic immune-mediated inflammatory disease that affects more than 6.8 million people worldwide8 and remains an area of substantial unmet medical need. Despite significant advances in treatment, many patients fail to achieve durable remission or lose response over time, resulting in frequent treatment switching. While biologic therapies have transformed outcomes for many patients, there remains a need for additional effective, well-tolerated treatment options. Convenient oral therapies are an important part of the treatment landscape, yet currently approved oral agents for IBD are limited by tolerability, safety concerns and/or modest efficacy.9
About cAMPfield Therapeutics
cAMPfield Therapeutics is a clinical-stage biopharmaceutical company focused on developing well-tolerated and highly effective oral medicines for immune-mediated inflammatory diseases, including inflammatory bowel disease. cAMPfield was founded by Mountainfield Venture Partners in partnership with executives who played key roles in the development and/or commercialization of Entyvio®, Humira®, Otezla®, and Zeposia®. cAMPfield holds exclusive global development and commercialization rights to prifemilast for all indications outside Greater China through a license agreement with Newsoara Biopharma Co., Ltd.
The company is headquartered in San Diego, California. For more information, visit www.campfieldtx.com.
About Newsoara Biopharma Co., Ltd.
Newsoara Biopharma Co., Ltd. (Newsoara) is an innovation-driven biopharmaceutical company founded in 2018 and headquartered in Shanghai, China. Newsoara is focused on the discovery and development of differentiated innovative therapies for autoimmune diseases, oncology and metabolic disorders. Newsoara has built an integrated drug development platform spanning drug discovery, translational research, clinical development and regulatory affairs, with a pipeline of 12 innovative drug candidates.
Newsoara has led the development of prifemilast (HY1999) in China, including preclinical development, CMC, Phase 1, Phase 2 and two Phase 3 clinical trials in moderate-to-severe plaque psoriasis. Newsoara plans to submit a New Drug Application (NDA) for prifemilast in plaque psoriasis in China by the end of 2026. Newsoara has granted cAMPfield Therapeutics exclusive development and commercialization rights to prifemilast for all indications outside Greater China, while retaining rights in Greater China.
Newsoara continues to advance a diversified pipeline across autoimmune diseases, oncology and metabolic disorders, with multiple programs progressing through clinical development, registration and approaching commercialization.
References
- Cai L, Zhang G, Wang L, et al. Superior efficacy of the oral phosphodiesterase 4B (PDE4B)-selective inhibitor prifemilast versus apremilast in moderate to severe plaque psoriasis: top-line results of a head-to-head phase 3 trial. Poster presented at: 26th Annual Fall Clinical Dermatology Conference; October 8-11, 2026; Las Vegas, NV.
- Cai L, Chen K, Li L, et al. Prifemilast, an oral phosphodiesterase 4B (PDE4B)-selective inhibitor, demonstrates rapid and durable efficacy with a favorable tolerability and safety profile in moderate to severe plaque psoriasis: results from phase 2 and 3 trials. Poster presented at: 26th Annual Fall Clinical Dermatology Conference; October 8-11, 2026; Las Vegas, NV.
- Vlachos C, Gaitanis G, Katsanos KH, et al. Psoriasis and inflammatory bowel disease: links and risks. Psoriasis (Auckl). 2016;6:73-92. doi:10.2147/PTT.S85194
- Danese S, Neurath MF, Kopoń A, et al. Effects of apremilast, an oral inhibitor of phosphodiesterase 4, in a randomized trial of patients with active ulcerative colitis. Clin Gastroenterol Hepatol. 2020;18(11):2526-2534.e9. doi:10.1016/j.cgh.2019.12.032
- Data on file. cAMPfield Therapeutics Inc; 2026.
- Otezla® (apremilast). Prescribing information. Amgen Inc; 2025.
- Ye L, Wang L, Tao X, et al. Pharmacokinetics, safety and tolerability of HPP737, a novel PDE4 inhibitor, in healthy Chinese participants: phase I study. Drug Des Devel Ther. 2026;20:598997. doi:10.2147/DDDT.S598997
- GBD 2017 Inflammatory Bowel Disease Collaborators. The global, regional, and national burden of inflammatory bowel disease in 195 countries and territories, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017. Lancet Gastroenterol Hepatol. 2020;5(1):17-30. doi:10.1016/S2468-1253(19)30333-4
- Ayoub M, Mattay S, Yarur AJ, Deepak P. Managing risks with newer oral small molecules in patients with inflammatory bowel diseases. Curr Gastroenterol Rep. 2024;26(5):145-156. doi:10.1007/s11894-024-00923-x
Media and Investor Contact
Rayne Rodgers
contact@campfieldtx.com
cAMPfield Therapeutics
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