The Dawn of Explosive Growth for IgA Nephropathy Therapeutics: The Next Blockbuster
Limited marketed treatment options paired with vast market potential have long made IgA nephropathy a fiercely contested arena for innovative pharmaceutical companies.
As the world's first approved etiology-targeted therapeutic for IgA nephropathy, budesonide enteric capsules (brand names: Nefecon, Tarpeyo; Chinese brand name: Naifukang) are widely regarded as the next blockbuster drug. According to Southwest Securities forecasts, annual sales of budesonide enteric capsules could reach RMB 5 billion by 2030.
Budesonide enteric capsules have already demonstrated blockbuster potential. In 2024, even without inclusion in the National Medical Insurance Catalog, the product generated RMB 353 million in sales over seven months. Bolstered by medical insurance-driven volume expansion and expanded indications in 2025, sales surged to over RMB 500 million in Q1–Q3 2025, representing a year-on-year increase of 3,699.89%.
Against this backdrop, budesonide enteric capsules are poised to become one of the innovative chronic disease drugs to hit RMB 1 billion in annual sales within its first year of medical insurance inclusion.
What underpins the stellar sales growth of budesonide enteric capsules?
Reviewing its development timeline, Nefecon was originally developed by Sweden's Calliditas Therapeutics as a delayed-release budesonide enteric capsule. Via proprietary formulation technology, it delivers budesonide specifically to mucosal B cells in the terminal ileum to exert local pharmacological effects. It received regulatory approvals in the United States in December 2021 and the European Union in July 2022, making it the world's first innovative therapy approved by both the U.S. FDA and European EMA for etiology-directed treatment of IgA nephropathy.
In June 2019, Everest Medicines entered into an exclusive licensing agreement with Calliditas Therapeutics, securing rights for the development and commercialization of Naifukang® in Greater China and Singapore. In November 2023, budesonide enteric capsules gained NMPA approval in China, becoming the first and only approved treatment for IgA nephropathy in the country and filling an unmet clinical gap.
Subsequently, the product was listed in the National Reimbursement Drug List (NRDL) in November 2024, with the negotiated reimbursement price formally implemented in January 2025. In May 2025, the NMPA granted full approval for the product, removing restrictions related to baseline proteinuria levels.
As the pioneering etiology-targeted therapy for IgA nephropathy globally, budesonide enteric capsules enjoy substantial first-mover advantages in the marketplace.
An Invisible Killer Afflicting Young Adults
Unmet clinical demand for IgA nephropathy treatment remains enormous.
Immunoglobulin A nephropathy (IgAN), the most prevalent primary glomerulonephritis worldwide, is a leading cause of chronic kidney disease (CKD) and end-stage renal disease (ESRD). The disease has long been plagued by high prevalence, low diagnostic rates, and a lack of disease-specific therapies.
Frost & Sullivan estimates that global IgA nephropathy patients totaled 9.2669 million in 2020 (including 2.2 million patients in China), and will rise to 9.7306 million by 2025 (2.3 million in China). Correspondingly, the global market for IgA nephropathy therapeutics is projected to expand from USD 567 million in 2020 to USD 1.196 billion in 2025, corresponding to a compound annual growth rate (CAGR) of 16.1%. The Chinese market is expected to grow from USD 37 million to USD 109 million over the same period, with a CAGR of 24.6%.
This rapid expansion is expected to be jointly driven by new drug launches, optimized medical insurance policies, and improved patient diagnosis rates.
IQVIA analysis incorporating multiple clinical studies shows the prevalence of IgA nephropathy in China is approximately 1.5–2 times that of Europe and 3–6 times that of the United States. Based on a European prevalence benchmark of 2.53 cases per 10,000 population across ten European countries, the total patient population with IgA nephropathy in China is estimated at roughly 5 million.
China records over 100,000 newly diagnosed IgA nephropathy cases annually, predominantly among adolescents and young adults aged 16 to 35. The vast majority of patients progress to end-stage renal disease within 10–15 years following diagnosis, requiring lifelong dialysis or kidney transplantation for survival and imposing severe financial burdens on individuals and their families.
Nevertheless, disease-specific etiology-targeted therapies for IgA nephropathy have long been absent.
Conventional clinical management primarily relies on supportive treatments including RAAS inhibitors, SGLT2 inhibitors and endothelin receptor antagonists to reduce urinary protein excretion, alongside systemic corticosteroids or immunosuppressants to mitigate inflammation. However, these traditional regimens fail to sustainably slow renal function decline and disease progression.
Studies indicate that patients receiving existing therapies still progress to end-stage renal disease prior to their projected life expectancy, with faster disease progression observed in Asian populations. Against this backdrop, there is an urgent clinical need for safer therapies acting at the root cause of the disease.
From Symptomatic Treatment to Etiology-Directed Treatment
The exact pathogenesis of primary IgA nephropathy has not been fully elucidated, with the widely accepted "multi-hit hypothesis" postulating that IgA nephropathy arises from a cascade of overlapping pathogenic mechanisms. For decades, treatment strategies for IgA nephropathy focused mainly on blood pressure and proteinuria control, representing symptomatic management.
The launch of budesonide enteric capsules addresses this major unmet medical need.
By targeting intestinal mucosal B cells and suppressing production of pathogenic galactose-deficient IgA1 (Gd-IgA1), the drug enables upstream intervention against disease etiology. The commercialization of budesonide enteric capsules has shifted treatment paradigms toward inhibiting pathogenic IgA1 synthesis, i.e., etiology-targeted therapy.
The distinctive mechanism of action underpins its core clinical strengths.
Each budesonide enteric capsule contains 4 mg budesonide. Utilizing a proprietary dual delayed and sustained-release formulation technology, the product delivers budesonide selectively to mucosal B cells in the terminal ileum. Upon capsule dissolution, triple-coated pellets release budesonide steadily and continuously, achieving high local drug concentrations across the target region. This suppresses formation of galactose-deficient IgA1 antibodies that trigger IgA nephropathy, intervening at the upstream stage of disease pathogenesis to treat IgA nephropathy. Furthermore, only approximately 10% of the absorbed drug enters systemic circulation following intestinal local uptake, resulting in low systemic exposure and favorable safety profiles.
Compared with conventional treatments, budesonide enteric capsules combine potent local anti-inflammatory activity, targeted intestinal delivery, sustained therapeutic efficacy and an acceptable safety profile.
Data from the Phase III NefIgArd trial demonstrates that following 9 months of treatment with Naifukang® and a subsequent 15-month off-treatment follow-up, the therapy delivered significant renoprotective effects within two years, slowing renal function decline by 66%; the risk of renal deterioration was reduced by roughly 66% relative to placebo-treated patients.
Modeling analysis based on the two-year overall eGFR slope from the NefIgArd trial predicts a median best estimate of 12.8 years delay to clinical renal endpoint progression for patients receiving budesonide enteric capsules.
Chinese patients derive even greater clinical benefits from Naifukang®. Subgroup analysis of Chinese participants in the NefIgArd study shows significant renoprotection over two years (9 months treatment plus 15-month post-treatment follow-up), with a ~66% reduction in renal function decline and sustained proteinuria reduction. The urine protein-to-creatinine ratio (UPCR) decreased significantly by 37.6% from baseline at month 9, with the therapeutic benefit well maintained throughout the off-treatment follow-up period, demonstrating numerically superior efficacy compared with the global patient cohort.
As a landmark therapeutic in IgA nephropathy management, budesonide enteric capsules have secured a vital clinical position in China by virtue of its unique intestinal-targeted mechanism, robust clinical efficacy (marked proteinuria reduction and preserved eGFR), and favorable safety profile. Both the 2025 KDIGO Clinical Practice Guideline for the Management of IgA Nephropathy and IgA Vasculitis and the Chinese Clinical Practice Guideline for Adult IgA Nephropathy and IgA Vasculitis (2025) explicitly list this agent as a first-line etiology-targeted therapy for IgA nephropathy.
From Monopoly to Multi-Polar Competition Landscape
Notably, the intellectual property journey of this first-in-class etiology-directed IgA nephropathy drug has been highly convoluted.
While budesonide enteric capsules (Nefecon®, Naifukang®) originated from early-stage research and development by Sweden's Calliditas Therapeutics AB, full global control of the asset has ultimately transferred to a Japanese enterprise.
In 2024, major Japanese chemical conglomerate Asahi Kasei completed the full acquisition of originator firm Calliditas, gaining full global rights to this flagship product at its source. Everest Medicines merely holds licensed rights for development and commercialization in Greater China, Singapore and South Korea, and spearheaded its approval as China's first etiology-targeted therapy for IgA nephropathy. This dynamic clearly illustrates deep Japanese industrial penetration and dominant negotiating power within the critical IgA nephropathy therapeutic segment, reflecting strategic ambition and control of the global innovative nephrology drug track among Japanese industrial capital.
Turning to the domestic market, on December 16, 2025, Hainan Herui Pharmaceutical Co., Ltd. received NMPA approval for its generic version of budesonide enteric capsules, securing China's first generic approval plus the first consistency evaluation certification for this product. Shijiazhuang Shiyao Zhongnuo Pharmaceutical and Qilu Pharmaceutical have also submitted applications under the new classification pathway, with their generic filings currently under review.
The approval of the first generic is set to reshape the competitive landscape surrounding this blockbuster asset amid a new round of industry restructuring.
Per IQVIA patient flow analysis, approximately 1.3 million IgA nephropathy patients are receiving treatment in China, with the patient population projected to approach 3 million by 2032 at an approximate annual compound growth rate of 8%. Rising diagnosis rates and medical insurance volume expansion will further fuel growth of China's IgA nephropathy therapeutics market.
Launch of the first generic version represents not only commercial strategy for pharmaceutical enterprises but also a tangible embodiment of national healthcare reform benefiting the general public. It enables grassroots hospitals and ordinary patients to access etiology-targeted treatment regimens, turning cutting-edge therapies from theoretically available into practically accessible options, bringing new hope for improved quality of life to vast numbers of IgA nephropathy patients across China.
With more pharmaceutical enterprises entering this space, the competitive landscape of the IgA nephropathy market is expected to evolve from a single-drug monopoly to multi-polar competition within the next three to five years.
