On 29 September, a conference call hosted by Huatai Securities on the IgA nephropathy treatment landscape placed the differentiated mechanism of ALEBUND-B (09637.HK) AP308 squarely in front of investors: directly degrading already-formed IgA and its immune complexes, with the aim of clearing existing deposits within the glomeruli.

Why does this pipeline, AP308, still awaiting human validation, deserve attention? The answer must be sought in the recent shifts taking place in innovative kidney disease drugs. As of the close on 6 October, ALEBUND-B (09637.HK) traded at HK$26.66, marking five consecutive sessions of gains and a cumulative rise of 13.7% from the 28 September close. Measured from the recent closing low of HK$23 on 14 September, the stock has rebounded 15.9% in total; over the same period the Hang Seng Index fell 2.6%, meaning the stock outperformed by roughly 18.5 percentage points. AP308 has become the focus of recent discussion, and the key lies in the new therapeutic entry point it proposes.

According to the company's announcement on 8 September, in a humanized IgA nephropathy mouse model, glomerular IgA deposits were almost completely cleared after eight consecutive weeks of dosing, with improvements in proteinuria and renal pathology. These are preclinical results; the US FDA has granted IND clearance, and China's National Medical Products Administration (NMPA) has also accepted its IND application, opening a path toward first-in-human trials. According to the conference call, the company expects to launch a Phase I study in China and Australia in early 2027, and to read out partial early efficacy and safety data in the second half of 2027, providing an observation window worth anticipating for proof of concept (PoC).

In summary, the highlights of ALEBUND are spread across four pipelines: AP308 explores etiological treatment of IgA; AP303 is positioned for disease-modifying therapy and multi-indication development; AP301's China marketing application has been accepted; and AP306 is advancing a global Phase IIb study. Recent attention on AP308 also means the market has begun to re-examine the portfolio value of this group of kidney disease assets.

Kidney disease assets are regaining attention, and recent BD deals and indication expansion provide a footnote: in 2023 Novartis acquired Chinook for up to US$3.5 billion (including up to US$300 million in contingent consideration), building out anti-APRIL and endothelin A receptor pipelines; in 2024 Vertex acquired Alpine for about US$4.9 billion, entering the BAFF/APRIL dual-target space. Multinational pharmaceutical companies are focusing on different therapeutic pathways, while AP308 attempts to degrade IgA and its immune complexes and clear already-formed glomerular deposits, offering a differentiated entry point.

Another example is Travere: FILSPARI was approved in April 2026 for a new FSGS indication, broadening growth expectations; its market capitalization rose from about US$3.47 billion at the end of 2025 to about US$5.43 billion on 5 October 2026, and Citi also raised its target price from US$70 to US$85. Compared with existing sales performance, what deserves more attention here is the value re-rating brought by the approval of a new indication. The market's interest in innovative kidney disease drugs is extending from IgA nephropathy to more disease types.

ALEBUND's AP303 starts from the shared pathological mechanisms of chronic kidney disease, connecting multiple treatment scenarios. This independently developed oral PPAR alpha/gamma dual agonist, for which the company holds global rights, simultaneously targets abnormal intraglomerular pressure, podocyte injury with inflammation and fibrosis, and tubular metabolic dysfunction, with development directions covering diabetic nephropathy, IgA nephropathy, autosomal dominant polycystic kidney disease and FSGS. Results from three Phase I/Ib studies were published in Kidney International Reports in August 2026, showing good safety and tolerability. Regulatory progress has also opened a path for multi-indication development: AP303 has received IND clearance to conduct Phase II clinical trials. Shared pathological mechanisms, multi-indication development and global rights make AP303 an important pillar for ALEBUND in expanding its kidney disease treatment footprint.

More near-term commercialization realization rests on AP301. The advantages of this next-generation iron-based phosphate binder lie in sustained phosphate reduction, a lower daily dose, and a capsule formulation that requires no chewing and has no odor. For dialysis patients who need long-term medication, these features are expected to reduce the burden of taking medication and improve the medication experience. China's pivotal Phase III RESPOND-1 study enrolled 474 maintenance dialysis patients across 50 centers; at week 52, AP301's serum phosphorus response rate was 66.7%, a relative improvement of about 13.8% over sevelamer's 58.6%. By total mass, AP301's daily dose is about 26.7% lower than sevelamer carbonate's roughly 10.40 grams. In other words, AP301 achieves a numerically higher long-term serum phosphorus response rate with a lower total daily formulation mass. It was generally safe and well tolerated over 52 weeks of treatment, with no obvious signal of iron overload risk observed.

In August 2026, AP301's China NDA was formally accepted, and a global Phase III multi-regional clinical trial is advancing in parallel; the company expects approval and launch in China in 2027, with the specific timing depending on regulatory review. In terms of commercialization potential, Bank of America Securities' initiation report estimates that, on a pre-risk-adjustment basis and after deducting distribution and related costs, AP301's China market revenue could reach about RMB 2.97 billion by 2035. For the US market, Huatai Securities estimates that product sales after restoring the risk discount could exceed US$1 billion.

Even more mechanistically innovative is AP306. Compared with phosphate binders that bind dietary phosphorus in the intestine, AP306 blocks active phosphorus absorption by simultaneously inhibiting three intestinal phosphate transporters, NaPi-IIb, PiT-1 and PiT-2, achieving phosphate reduction at a lower dosage. In the completed China Phase II study, at week 12 the AP306 group's serum phosphorus fell by an average of 0.81 mmol/L (2.51 mg/dL) from baseline; over the same period, 44% of patients in the AP306 group reached the KDIGO-recommended serum phosphorus range of 0.81-1.45 mmol/L (2.5-4.5 mg/dL), compared with 21% in the trial's positive control, sevelamer carbonate.

Dosing convenience is also a differentiated advantage of AP306. The company's prospectus and the Bank of America research report note that AP306 requires only 2-3 small tablets per day, compared with the burden of 6-12 tablets per day for traditional phosphate binders, making long-term use easier for dialysis patients. AP306 received NMPA breakthrough therapy designation in June 2024. Recent Goldman Sachs China biopharma trip notes show that management believes AP306 is expected to establish advantages in efficacy, diarrhea rates and discontinuation rates, and to cover different patient and payer groups alongside AP301.

On the commercialization path, ALEBUND has granted R1 Therapeutics the development, manufacturing and commercialization rights for AP306 outside Greater China; R1's shareholders include DaVita and U.S. Renal Care, two leading US kidney care providers. The global Phase IIb multi-regional clinical trial has completed randomization and dosing of the first subject. Bank of America Securities' initiation report estimates that AP306's peak sales could exceed RMB 3.4 billion in the China market and exceed US$3.4 billion in the US market.

Subsequent catalysts are also gradually taking shape. The advancement of AP301's China review and the company's expected 2027 approval will bring nearer-term commercialization observation opportunities; its global Phase III is expected to be completed in the second quarter of 2027. AP306's global Phase IIb is likewise expected to be completed in the second quarter of 2027, and the company will disclose top-line data in due course and plans to launch a global Phase III study in the second half of 2027. AP303 is advancing development around a basket Phase II in diabetic nephropathy and IgA nephropathy, as well as two Phase II multi-regional studies in ADPKD and FSGS, and its multi-indication layout will continue to enrich the company's clinical catalysts. AP308 is expected to bring early PoC-related data in the second half of 2027.

From AP301's registration and commercialization, to AP306's global clinical advancement, and on to AP303's multi-indication development and AP308's mechanistic innovation, ALEBUND has a continuous series of observation nodes. What is worth noting behind the five consecutive gains is that new mechanisms in the kidney disease industry, commercialization upside and the company's own pipeline progress are beginning to echo one another.