Protagonist Therapeutics Inc. got a win in its phase IIb study and is making plans for a phase III. JNJ-2113 (formerly PN-235), an oral, interleukin-23 receptor antagonist peptide, hit its primary efficacy endpoint in treating moderate to severe plaque psoriasis. A statistically significant greater proportion of the participants receiving JNJ-2113 saw a 75% improvement in their skin lesions compared to placebo at week 16.
Hepcidin deficiency in hereditary hemochromatosis (HH) leads to increased absorption of dietary iron and thus iron overload. Rusfertide is a hepcidin mimetic peptide that has shown efficacy at reducing the need for therapeutic maintenance phlebotomy in patients with HH. Researchers aimed to evaluate the benefits of cotreatment with a hepcidin mimetic peptide plus the rusfertide analogue PN-23114 (Protagonist Therapeutics Inc.) at 7.5 mg/kg t.i.w. and phlebotomy in a murine model of HH.
Protagonist Therapeutics Inc. has disclosed hepcidin mimetic conjugates acting as solute carrier family 40 member 1 (SLC40A1, ferroportin) ligands with extended half-life and stability.
The May 2014 approval of Takeda Pharmaceutical Co. Ltd.’s Entyvio (vedolizumab) brought welcome news in the form of an important mechanism of action for patients with ulcerative colitis and Crohn’s disease, but also means a burdensome course of administration – 30 minutes’ worth of infusion every six weeks, a drawback that other developers are trying to remedy. Standouts among the up-and-comers are Morphic Holding Inc., with an oral candidate that works through the same mechanism of action as Entyvio, and Protagonist Therapeutics Inc.
Protagonist Therapeutics Inc. continues having a tough time. The latest is a steep stock drop after a phase II trial in ulcerative colitis (UC) missed its primary endpoint, but the company insists the data are good enough to move into phase III. Top-line data showed a 450-mg BID dose of PN-943 in treating moderate to severe UC missed its primary endpoint, which was the number of participants achieving clinical remission at week 12 compared to placebo.
It’s been one thing after another for rusfertide from Protagonist Therapeutics Inc. for the past year. Now the U.S. FDA has told the company it wants to rescind the breakthrough designation, a relatively rare occurrence, based on observed malignancies in a follow-up to September’s clinical hold.
Shares of Protagonist Therapeutics Inc. (NASDAQ:PTGX) climbed 93.9% on Oct. 11 after the FDA removed a full clinical hold on studies of the rusfertide, the company's investigational treatment for the blood disorders polycythemia vera and hereditary hemochromatosis. Triggered by a finding of malignant skin tumors in mice treated with the drug disclosed on Sept. 17, the FDA's three-weeks-ago hold had pushed Protagonist shares down by as much as 72%.
Shares of Protagonist Therapeutics Inc. (NASDAQ:PTGX) fell 62% to $17.53 on Sept. 17 after it reported finding malignant skin tumors in a mouse model test of its most advanced candidate, rusfertide for blood disorders. After the company notified the FDA, the regulator put the program on a clinical hold, leading dosing of patients in all ongoing trials of rusfertide to be halted for now. The development could impact Protagonist's ability to start phase III testing of the candidate in polycythemia vera (PV) early in 2022, as well as efforts to expand its development to a third indication beyond PV and hereditary hemochromatosis (HH) by the end of this year, as it has planned.
“All along our guidance has been that, look, we are doing multiple open-label studies with the intent of picking a winner,” said Protagonist Therapeutics Inc. CEO Dinesh Patel during a conference call with investors. “Today, we have picked a winner by a huge margin” in the shape of PTG-300, an injectable hepcidin mimetic for the rare blood cancer polycythemia vera (PV).
Protagonist Therapeutics Inc. stock (NASDAQ:PTGX) nosedived 47% on Tuesday after the company released preliminary results from its phase II open-label study of PTG-300, an injectable hepcidin mimetic to treat patients with transfusion-dependent beta-thalassemia.
