Izokibep

Affibody shared updated data at the EULAR conference in London.\n Affibody may not have expected to be working on izokibep again, but the Swedish biotech hasn’t wasted an opportunity to showcase the inflammation drug’s potential to prospective partners.Stockholm-based Affibody licensed izokibep to California’s Acelyrin for $25 million upfront back in 2021. But the IL-17A inhibitor boomeranged back to Affibody around the time that Acelyrin decided to merge into Alumis last year.“Of course, it was a big surprise,” said Affibody\'s director of corporate development Maria Åkerman, Ph.D., who also serves as project lead for izokibep.Åkerman spoke to Fierce on the sidelines of the European Alliance of Associations for Rheumatology (EULAR) conference in London Wednesday, where Affibody presented data that it claimed showed izokibep’s best-in-class profile across both psoriatic arthritis (PsA) and hidradenitis suppurativa (HS).“Given that we just recently got it back, we are super proud of the data,” she said. “When we\'ve reconnected with the medical field about this, there’s been great enthusiasm.”Izokibep already aced a phase 2b/3 PsA trial under Acelyrin’s guidance back in 2024, when the drug was shown to hit its endpoint of the proportion of patients who saw a 50% or greater improvement in rheumatology symptoms at Week 16.At about one-tenth the size of a monoclonal antibody, izokibep was engineered to reach difficult-to-treat tissues by incorporating an albumin-binding domain that is meant to also improve the therapy’s pharmacokinetic properties. Affibody brought Week 52 data along to EULAR this week to remind people of what the drug can do when compared to PsA mainstays like Novartis’ Cosentyx and UCB’s Bimzelx. Affibody’s slides show izokibep holding its own on measurements like a 50% improvement in rheumatology symptoms (ACR50), as well as a 70% improvement and the proportion of patients who saw a 100% improvement in psoriasis area and severity (PASI100).“ACR50 is sort of the minimal endpoint that you want to reach in order to be successful in this field, but we usually say for izokibep that the higher the bar, the better we are,” Åkerman said.“When you come to the harder-to-reach endpoints—for example, the combination ACR50 and PASI100—people see that there is a field that crystallizes out where you can see what compounds perform the best,” she added. “And we see that izokibep stands out really well.”While Bimzelx and Moonlake Therapeutics’ own arthritis hopeful sonelokimab inhibit both IL-17A and IL-17F, Åkerman is confident in izokibep’s design of only targeting the former. “We know some of the other players in the field emphasize that there is an advantage with targeting IL-17A and F, but we believe our clinical data prove that that\'s not necessarily the case,” she said.Izokibep previously had a slightly tougher time in HS, with Acelyrin reporting back in 2023 that the drug had flunked the second part of a phase 2b/3 study in this inflammatory skin condition. While the trial had failed to hit the mark of a greater than 75% reduction in patients’ abscess and inflammatory nodule count at Week 16, Åkerman said plans for HS are now “back on track.”“There was a clear difference in response between Week 12 and Week 16, and this is known in the field as ‘the HS wobble,’” she said. “So a study can perform extremely well at some time points, but not well in the others.” “The phase 3 data look really, really good,” Åkerman added.Backed by this data, Åkerman said izokibep is only “one study away” from being able to go to regulators. But the plan isn’t for Affibody to see this story through to the end.“We\'re looking for a new home for izokibep,” Åkerman explained. “We could probably pull off a pivotal trial in one of these indications—maybe HS in particular—but the primary goal for Affibody is radiopharmaceuticals, so we\'re more geared towards oncology.”It’s true that although the recently returned izokibep may be the most clinically advanced candidate in the Swedish biotech’s pipeline, the company’s top priority is advancing ABY-271. Affibody is currently dosing the radioligand in the second part of a phase 1 study of patients with HER2-expressing tumors. Another study is penciled in for the second half of next year.Åkerman was unable to share whether Affibody has any buyers lined up for izokibep, but she told Fierce there are ongoing “discussions with several players.”While Affibody may have moved on from izokibep, Åkerman still holds a flame for the inflammation drug.“I would love to go ahead with this [program], but it\'s not my decision,” she said.