Protagonist soars as it posts positive top-line results in JNJ-2113 trial

Protagonist Therapeutics’ (Nasdaq: PTGX) shares closed up a massive 52% at $23.09 yesterday, after it announced positive top-line results from the FRONTIER 1 Phase IIb clinical trial evaluating the oral Interleukin-23 receptor (IL-23R) antagonist peptide JNJ-2113 in patients with moderate-to-severe plaque psoriasis.

JNJ-2113 is being developed under a collaboration with US healthcare giant Johnson & Jonson’s (NYSE: JNJ) Janssen Biotech unit. JNJ-2113 appears to be the only oral IL-23 project in development, with Protagonist previously abandoning other J&J-partnered assets, PTG-200 and PN-232.

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.