Oxylanthanum Carbonate Achieves Serum Phosphate Control with Significantly Lower Pill Burden in Patients with Hyperphosphatemia on Dialysis

Background: High pill burden and GI side effects from phosphate binders (PB) contribute to low adherence to treatment of hyperphosphatemia (HP). Oxylanthanum carbonate (OLC), a lanthanum-based PB in development for treating HP in chronic kidney disease (CKD), uses proprietary nanoparticle technology and is formulated in small, swallowable tablets. In a pivotal open-label clinical trial, OLC was safe and well tolerated. We present new findings on sP levels, pill volume, and pill quantity in patients (pts) with HP treated with OLC compared to their pretrial PB regimen. Methods: This open-label, single-arm, multicenter, multidose study enrolled CKD pts on dialysis with mean historical sP ≥4.0 and ≤7.0 mg/dL for ≥8 weeks. The study consisted of screening, washout, titration, and maintenance periods. After washout, pts received OLC 500mg TID, titrated to a max of 1000mg TID over 6 weeks followed by a 4-week maintenance period. Daily pill volume was calculated by multiplying the pill volume per tablet by the number of tablets per day of pretrial PBs at screening and of OLC tablets at the end of study. Pretrial PB included sevelamer carbonate, calcium acetate, ferric citrate, and sucroferric oxyhydroxide. Results: Of 128 pts screened, 86 were enrolled, 72 completed the study, and 70 had pretrial binder data. The sP was ≤5.5 mg/dL at screening in 59% of pts and at the end of OLC titration in 91% of pts. The mean daily pill volume of pretrial binders at screening was 9.3 cm3 with a mean of 8.3 pills/day, compared to mean daily pill volume at study end with OLC of 1.4 cm3 with a mean 3.9 pills/day (Figure 1). Conclusion: OLC reduced sP below 5.5 mg/dL in >90% of pts by end of titration. Mean daily pill volume and pill number were significantly reduced with OLC compared to pts’ pretrial PBs. Combined with previously presented safety data, these findings suggest that OLC is safe, effective, and well-tolerated. Its small, easy-to-swallow formulation may be a welcome choice for pts with HP. Funding: Commercial Support - Unicycive Therapeutics, Inc.