Drugs for IgA nephropathy are on the eve of explosive growth.

01
The Next Blockbuster Drug
The scarcity of marketed drugs and vast market space once made IgA nephropathy a highly contested battleground for innovative pharmaceutical companies.
As the world’s first approved etiological treatment for IgA nephropathy, budesonide enteric coated capsules (brand name: Nefecon / Tarpeyo / 耐赋康) is regarded as the next blockbuster drug. Southwest Securities predicts that sales of budesonide enteric coated capsules could reach 5 billion yuan by 2030.
Budesonide enteric coated capsules have already begun to show clear market leadership potential.
In 2024, before being covered by medical insurance, the product achieved sales of 353 million yuan in seven months. With volume growth driven by insurance coverage and expanded indications in 2025, sales of budesonide enteric coated capsules surged to over 500 million yuan in Q1–Q3 2025, representing a year-on-year increase of 3,699.89%.
At this rate, budesonide enteric coated capsules is on track to become one of the few innovative chronic disease drugs to reach the 1-billion-yuan sales level in its first year of medical insurance coverage.
Why has budesonide enteric coated capsules seen such a steep upward trajectory in sales?
Looking back at its launch history, Nefecon was developed by Sweden’s Calliditas Therapeutics. It is a delayed-release budesonide enteric coated capsule designed through specialized manufacturing technology to targetedly release budesonide to mucosal B cells in the terminal ileum, exerting local pharmacological effects. It was approved in the U.S. in December 2021 and in the EU in July 2022, making it the first innovative drug approved by both the U.S. FDA and the European EMA for the treatment of IgA nephropathy.
In June 2019, Everest Medicines signed an exclusive license agreement with Calliditas Therapeutics, obtaining rights to develop and commercialize Nefecon® in the Greater China Region and Singapore. In November 2023, budesonide enteric coated capsules was approved by China’s NMPA, becoming the first and only approved drug for IgA nephropathy in China, filling a critical clinical treatment gap.
Subsequently, in November 2024, budesonide enteric coated capsules was included in China’s National Medical Insurance Drug List (NRDL), with the reimbursement price taking effect in January 2025. In May 2025, the product received full approval from NMPA to remove the proteinuria level restriction.
As the world’s first approved etiological therapy for IgA nephropathy, budesonide enteric coated capsules commands substantial first-mover advantages in the market.

02
A "Silent Killer" Among Young and Middle-Aged Adults
There is a huge unmet clinical need for IgA nephropathy.
As the most common primary glomerulonephritis worldwide, Immunoglobulin A Nephropathy (IgA Nephropathy, IgAN) is one of the leading causes of Chronic Kidney Disease (CKD) and End-Stage Renal Disease (ESRD). It has long been trapped in a dilemma of high prevalence, low diagnosis rate, and lack of specific treatments.
According to Frost & Sullivan, the global number of patients with IgA nephropathy reached 9.2669 million in 2020 (including 2.20 million in China) and is projected to reach 9.7306 million by 2025 (including 2.30 million in China).Accordingly, the global market for IgA nephropathy therapeutics is expected to grow from $567 million in 2020 to $1.196 billion by 2025, with a CAGR of 16.1%.The Chinese market will rise from $37 million to $109 million over the same period, with a CAGR of 24.6%.
This rapid growth is expected to be driven by the launch of new drugs, optimized medical insurance access policies, and improved patient diagnosis rates.
This rapid growth is expected to be driven by the launch of new drugs, optimized medical insurance access policies, and improved patient diagnosis rates. Based on a comprehensive analysis of multiple studies, IQVIA reports that 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.Using the latest prevalence rate of 2.53 per 10,000 people across ten European countries, the estimated number of IgA nephropathy patients in China is about 5 million.
China sees over 100,000 new confirmed cases of IgA nephropathy each year, predominantly affecting young adults aged 16–35. The vast majority of patients progress to end-stage renal disease within 10–15 years of diagnosis, requiring dialysis or kidney transplantation to sustain life, placing a heavy economic burden on individuals and their families.
Yet for a long time, no specific etiological treatments have been available for IgA nephropath.
Clinical management has mainly relied on conventional supportive care to reduce proteinuria, represented by RAAS inhibitors, SGLT2 inhibitors, and endothelin receptor antagonists, as well as systemic glucocorticoids or immunosuppressants to alleviate inflammation. However, none of these conventional treatments can sustainably delay renal function decline and disease progression.
Studies have shown that patients still progress to end-stage renal disease before their normal life expectancy under existing regimens, with faster progression among Asian patients. Against this background, the development of safer drugs targeting the root cause of the disease has become an urgent clinical demand.

03
From Symptomatic to Etiological Treatment
The pathogenic mechanism of primary IgA nephropathy has not yet been fully elucidated. The widely accepted theory is the multi-hit hypothesis, which states that IgA nephropathy is caused by the combined effect of multiple mechanisms.
The emergence of budesonide enteric coated capsules has addressed this unmet need.
By targeting intestinal mucosal B cells and inhibiting the production of pathogenic Gd-IgA1, it intervenes in the disease at its source. With the launch of budesonide enteric coated capsules, the treatment paradigm is shifting toward suppressing the production of pathogenic IgA1 — namely, etiological treatment.
The unique mechanism of budesonide enteric coated capsules is the core source of its clinical advantages.
Each capsule contains 4 mg of budesonide. Through a special dual delayed release and sustained release formulation technology, budesonide is targetedly delivered to mucosal B cells in the terminal ileum. After the capsule dissolves, the three layer coated pellets release budesonide continuously and steadily, covering the entire target area at high concentration. This reduces the production of galactose deficient IgA1 antibodies that induce IgA nephropathy, intervenes in the upstream stage of the pathogenic mechanism, and achieves the therapeutic effect for IgA nephropathy. In addition, only approximately 10% is absorbed systemically after local intestinal uptake, resulting in low systemic exposure and high safety.
Compared with traditional therapeutic drugs, budesonide enteric coated capsules achieve effective local anti inflammation, targeted delivery, durable therapeutic effect, and favorable safety.
According to data from the NefIgArd Phase III clinical study, 9 months of treatment with Nefecon® followed by 15 months of follow up off treatment resulted in significant renal function protection over 2 years, delaying renal function decline by approximately 66%. The rate of renal function deterioration was also about 66% lower in the treated group than in the placebo group.
Based on the overall 2 year eGFR slope from NefIgArd, modeling analysis predicted that the best median estimate for delaying clinical endpoints in the budesonide enteric coated capsule group was 12.8 years.
Chinese patients derive even greater benefit from Nefecon®. Data from the Chinese subgroup of the NefIgArd study showed that 9 months of treatment with Nefecon® followed by 15 months of follow up off treatment provided clinically meaningful renal function protection over 2 years, reducing renal function decline by approximately 66%.Sustained reduction in proteinuria was also observed: the urine protein to creatinine ratio (UPCR) decreased by 37.6% from baseline at 9 months, and this reduction was well maintained during the 15 month follow up period — numerically superior to the benefit seen in the global population.
As a milestone drug in the field of IgA nephropathy treatment, budesonide enteric coated capsules have established an important clinical position in the Chinese market, thanks to their unique intestinal targeted mechanism, proven clinical efficacy (significant proteinuria reduction and eGFR protection), and favorable safety profile.
Both the 2025 KDIGO Clinical Practice Guideline for the Management of IgA Nephropathy and IgA Vasculitis and the 2025 Chinese Clinical Practice Guideline for Adult IgA Nephropathy and IgA Vasculitis Nephritis clearly list it as a first line etiological treatment for IgA nephropathy.

04
From Monopoly to Multipolarity
Notably, the ownership evolution of this globally pioneering etiological treatment for IgA nephropathy has been full of twists and turns.
Although budesonide enteric coated capsules (NEFECON®, 耐赋康 ®) were initially developed by Sweden’s Calliditas Therapeutics AB, full control has since been transferred to a Japanese enterprise.
In 2024, Asahi Kasei, a Japanese chemical giant, acquired Calliditas in its entirety, securing global rights to this core product at the source. Everest Medicines only obtained development and commercialization rights for Greater China, Singapore and South Korea through a licensing agreement, and spearheaded its approval as the first etiological treatment for IgA nephropathy in China. This landscape clearly demonstrates that Japan’s enterprises have deeply penetrated and secured key influence in the important field of IgA nephropathy treatment, highlighting the strong ambition and strategic control of Japanese industrial capital over the global nephrology innovative drug sector.
Turning to the domestic market: on December 16, 2025, budesonide enteric coated capsules from Hainan Herui Pharmaceutical Co., Ltd. received official approval from China’s National Medical Products Administration (NMPA), becoming the first generic version and first to pass consistency evaluation in China. CSPC Zhongnuo Pharmaceutical (Shijiazhuang) Co., Ltd. and Qilu Pharmaceutical have closely followed, both having filed applications under the new classification and being under review.
With the approval of the first generic drug, a new round of shifts is taking shape in the market landscape surrounding this blockbuster product.
According to IQVIA analysis of patient flow for IgA nephropathy, approximately 1.3 million patients are currently receiving treatment in China, and this number is expected to reach nearly 3 million by 2032, representing a compound annual growth rate of about 8%. Driven by rising diagnosis rates and volume growth from medical insurance coverage, China’s IgA nephropathy market will expand further.
The launch of the first generic drug reflects not only companies’ commercial strategies but also national medical reform benefiting the general public. It enables more grassroots hospitals and ordinary patients to access etiological treatment, turning cutting edge therapies from “visible” to “affordable and accessible”, and bringing new hope for high quality survival to a much broader group of Chinese IgA nephropathy patients.
With more pharmaceutical companies entering the arena, the competitive landscape of the IgA nephropathy market is expected to evolve from “monopoly” to “multipolarity” over the next 3–5 years.