Unicycive's pivotal trial of rival to Takeda kidney drug hits main goal, clearing path to FDA filing

Unicycive Therapeutics has laid the groundwork for entering a market targeted by Sanofi and Takeda, posting pivotal bioequivalence data on a candidate designed to improve compliance with kidney disease treatment regimens.

Patients with chronic kidney disease on dialysis who develop hyperphosphatemia, an electrolyte disorder associated with hospitalization and death, already have multiple phosphate-binding treatment options. Takeda entered the space through its takeover of Shire, which gave it control of Fosrenol chewable tablets, and Genzyme, now part of Sanofi, won approval for Renvela more than 20 years ago.

Faced with well-established incumbents, Unicycive, like Shire before it, has identified reduced pill burden as a way to muscle in on the market. Unicycive’s prospect, Renazorb, is another phosphate-binding agent, but it is potentially differentiated through nanotechnology.

To enter the market, Unicycive ran a randomized, open-label, two-way crossover study that enrolled 40 subjects per treatment arm to establish pharmacodynamic bioequivalence between Renazorb and Fosrenol. The study met its primary endpoint.

Buoyed by the data, Unicycive plans to file for FDA approval around the middle of the year. The plan is based on feedback from the FDA that a single bioequivalence study in healthy volunteers can meet the clinical regulatory requirements for filing via the 505(b)(2) pathway.

If approved, Renazorb will provide a new, potentially more convenient option for hyperphosphatemia patients. Some patients on Renvela need to swallow nine tablets a day. Fosrenol has a lower pill burden, with patients typically starting on three doses a day, but Unicycive thinks the large size of the tablets and the need for patients to chew them are downsides of the product.

Unicycive, which acquired Renazorb from Spectrum Pharmaceuticals in 2018, sees the smaller pill size, lower number of pills and improved palatability of its challenger combining to improve compliance and disease management. The features of Renazorb stem from the use of nanoparticle technology.