Alebund Pharmaceuticals announced positive topline results from its pivotal phase 3 study of AP301, a novel fiber-iron-based phosphate binder, for treating hyperphosphatemia in dialysis patients. The company achieved database lock on June 16, 2025, with the trial meeting its primary endpoint and demonstrating statistically significant and clinically meaningful improvement in serum phosphorus control.
Study Design and Results
The pivotal study (NCT07030595, CTR20231624) was a randomized, open-label, active-controlled, multi-center phase 3 trial designed to evaluate the efficacy and safety of AP301 in controlling serum phosphorus levels in dialysis patients with hyperphosphatemia. The 52-week study included an active control phase, an AP301 low-dose control phase, and an extended treatment phase, with sevelamer carbonate serving as the active comparator throughout the entire study period.
A total of 474 participants were randomized across 50 investigational sites in China, with the study led by Professor Li ZUO, Director of the Department of Nephrology at Peking University People's Hospital. The safety profile of AP301 was favorable and consistent with previous studies.
Novel Mechanism and Patient Benefits
As a novel fiber-iron-based phosphate binder, AP301 provides several advantages over existing treatments. The drug offers high phosphate-binding capability, requires no chewing before swallowing, shows no volume expansion when exposed to gastric fluid, and has no systemic absorption. These properties contribute to a reduced pill burden, good tolerability, and improved patient compliance.
"In the completed phase 2 study, AP301 was shown to be safe, well tolerated, and can effectively lower serum phosphorus in a dose-dependent manner," commented Dr. Jin Tian, Co-founder and CMO of Alebund. "This pivotal trial further demonstrates the clinical value of AP301, which has the potential to advance the treatment option for millions of patients with hyperphosphatemia through further increasing their adherence."
Addressing Unmet Medical Need
Hyperphosphatemia represents one of the most common complications in chronic kidney disease (CKD) patients. Long-term elevated serum phosphorus levels can cause multiple complications including secondary hyperparathyroidism, renal osteodystrophy, and vascular calcification, serving as an independent risk factor for cardiovascular events and all-cause mortality.
For CKD patients undergoing dialysis treatment, regular dialysis is insufficient to remove the overload of serum phosphate in the body. While oral phosphate binders represent the prevailing treatment for hyperphosphatemia, patient compliance remains low, with less than 50% reaching good phosphate control due to gastrointestinal side effects and high pill burden.
According to the Global and Chinese Hyperphosphatemia Drug Industry Blue Book by China Insights Consultancy in 2023, the out-of-target rate of serum phosphorus levels in dialysis patients in Chinese mainland was significantly higher than other countries and regions, indicating substantial room for improvement in phosphorus binder usage.
Regulatory Timeline and Market Opportunity
Alebund plans to engage with the China National Medical Products Administration (NMPA) regarding its new drug application plan in the third quarter of 2025. Detailed results from this phase 3 study will be presented at an upcoming medical conference.
The market size of serum phosphorus lowering products in China is expected to reach 10 billion RMB by 2035, representing a significant commercial opportunity for effective treatments that can improve patient compliance and outcomes.
Company Pipeline
Alebund, incubated in Shanghai in 2018, focuses on the discovery, development, production, and commercialization of novel therapies primarily for kidney diseases and their complications. The company has built a diversified pipeline targeting various renal indications, including chronic kidney disease/dialysis complications, IgA nephropathy, diabetic kidney disease, focal segmental glomerulosclerosis (FSGS), and autosomal dominant polycystic kidney disease (ADPKD).
The company has completed construction of its manufacturing site for small molecules in Yangzhou that will supply bulk quantities of Alebund's pipeline drugs, including AP301, upon commercial launch. Alebund has also established a dedicated commercialization team in China responsible for the commercial promotion of renal products.
