JNJ-2113 (formerly PN-235) met the study’s primary endpoint, with a statistically significantly higher proportion of adult patients with moderate-to-severe plaque psoriasis achieving PASI-75 in all treatment groups at Week 16 compared to placebo

Treatment was well tolerated, with no meaningful difference in frequency of adverse events across treatment groups

NEWARK, CA, USA I March 7, 2023 I Protagonist Therapeutics, Inc. (Nasdaq: PTGX) (“Protagonist” or “the Company”), today announced positive topline results from its collaboration with Janssen Biotech, Inc., one of the Janssen Pharmaceutical Companies of Johnson & Johnson (Janssen), in the FRONTIER 1 Phase 2b clinical trial evaluating the oral Interleukin-23 receptor (IL-23R) antagonist peptide JNJ-2113 in patients with moderate-to-severe plaque psoriasis.

Data from the 255-patient study showed that JNJ-2113 achieved the study’s primary efficacy endpoint, with a statistically significant greater proportion of patients who received JNJ-2113 achieving PASI-75 (a 75% improvement in skin lesions as measured by the Psoriasis Area and Severity Index) responses compared to placebo at Week 16 in all five treatment groups. A clear dose response was observed across an eight-fold dose range. Treatment was well tolerated, with no meaningful difference in frequency of adverse events across treatment groups versus placebo. Data will be presented from various pre-clinical and clinical studies on JNJ-2113 at medical conferences beginning in the second quarter of 2023.

“We are thrilled to be at this transformative junction, with JNJ-2113 being the first- and only-in-class oral IL-23 receptor antagonist as a potential oral targeted therapy for plaque psoriasis, further underscoring the strength of our innovative peptide technology platform. A full measure of JNJ-2113 should be evident when the FRONTIER 1 Phase 2b data are shared at an upcoming medical conference. It is our expectation that JNJ-2113 will progress into a Phase 3 registrational study in plaque psoriasis on the strength of these data. We are excited about JNJ-2113’s potential prospects across the spectrum of additional IL-23 mediated diseases,” said Dinesh V. Patel, Ph.D., President and Chief Executive Officer at Protagonist.

Dr. Patel continued, “We see this as a watershed moment for Protagonist, the industry, and patients by successfully targeting a systemic immunomodulatory IL-23 monoclonal antibody pathway through an oral peptide antagonist. We are humbled to be part of this significant scientific breakthrough.”

JNJ-2113 Clinical Trials

The FRONTIER 1 Phase 2b trial (NCT05223868) was designed to assess the efficacy and safety of JNJ-2113 in patients with moderate-to-severe plaque psoriasis. It is a randomized, multicenter, double-blind, placebo-controlled study that evaluated three once-daily dosages and two twice-daily dosages of JNJ-2113 taken orally. The primary endpoint of the study is the proportion of patients achieving PASI-75 at 16 weeks.

Beyond the recently completed Phase 2b FRONTIER 1 study and a Phase 1 trial (NCT05062200) in healthy Japanese and Chinese participants, JNJ-2113 is currently being studied in multiple trials, also led by Janssen. FRONTIER 2 (NCT05364554) is a long-term extension study of JNJ-2113 in adults with moderate to severe plaque psoriasis; the SUMMIT Phase 2a trial (NCT05357755) is testing a delayed release JNJ-2113 tablet versus placebo in adults with moderate to severe plaque psoriasis; and a Phase 1 trial (NCT05703841) of an immediate release formulation of JNJ-2113 in healthy Chinese adult participants is currently recruiting.

Janssen License and Collaboration Agreement

JNJ-2113 (formerly known as PN-235) was discovered and is being developed pursuant to the license and collaboration agreement between Protagonist and Janssen Biotech, Inc., one of the Janssen Pharmaceutical Companies of Johnson & Johnson. Protagonist completed a Phase 1 study of JNJ-2113 in healthy volunteers in October of 2021 and Janssen retains exclusive, worldwide rights to develop in Phase 2 and beyond, and to commercialize compounds derived from the research conducted pursuant to the agreement against a broad range of indications.

About Protagonist

Protagonist Therapeutics is a biopharmaceutical company with peptide-based new chemical entities rusfertide and JNJ-2113 (formerly PN-235) in advanced stages of clinical development, both derived from the Company’s proprietary technology platform. Rusfertide, a mimetic of the natural hormone hepcidin, is the Company’s lead drug candidate, currently in a global Phase 3 stage of development. The Phase 3 VERIFY and Phase 2 REVIVE studies of rusfertide in polycythemia vera are ongoing. Protagonist retains all worldwide development and commercialization rights to rusfertide.

Advancement of JNJ-2113 into a Phase 3 study and meeting the primary endpoint in that study would qualify Protagonist for milestone payments of $50 million and $115 million, respectively. In total, Protagonist remains eligible for up to $855 million in various milestone payments and tiered royalties based on worldwide net drug sales.

SOURCE: Protagonist Therapeutics