A Study to Evaluate Safety, Tolerability and Efficacy of AP306 at Fixed Doses in Dialysis Participants With Hyperphosphatemia

Important Inclusion Criteria: * Signs a written informed consent form (ICF) and is willing to comply with all study requirements in the study * Receiving a stable hemodialysis (including hemodialysis, hemodiafiltration, and hemoadsorption) regimen, which is defined as a frequency of three times per week for at least 12 weeks before signing the ICF, and does not plan to change in the study * Who has a blood phosphate level within the study-required range * Who has a dialysis adequacy, assessed by single pooled Kt/V (SpKt/V, estimated with blood urea) ≥1.20, at screening or any documented value ≥1.20 within 12 weeks prior to signing the ICF * If the participant is receiving etelcalcetide, their doses must be unchanged for at least 4 weeks prior to signing the ICF * If the participant is receiving any of the following therapies, their doses are stable for at least 14 days prior to signing the ICF: phosphate-lowering products other than tenapanor or phosphate binders, active vitamin D and analogs, cinacalcet, calcitonin, and P-glycoprotein inhibitors * Agreement to use highly effective contraception for women of childbearing potentially and non-sterile sexually active males throughout the study and for 90 days after the final dose of study drug Important Exclusion Criteria: * Pregnant or breastfeeding * Scheduled for a living donor kidney transplant in the next 6 months, planned change to peritoneal dialysis or home hemodialysis in the study; planned relocation to another dial…