GSK Acquisition Entry: Is the "Oligarch Era" of CSU Treatment Facing Another Shift?
"Off the Beaten Path" Major Track, Adding Fuel to the Fire.On January 20, GSK announced the acquisition of U.S.-listed pharmaceutical company RAPT Therapeutics. RAPT is a biopharmaceutical company focused on novel therapies for inflammatory and immune diseases. Its core asset, ozureprubart, is a novel half-life extended monoclonal antibody for the treatment of food allergy (FA) and chronic spontaneous urticaria (CSU), currently in Phase IIb clinical development.Under the terms of the agreement, GSK paid RAPT Therapeutics $58 per share, estimating the total equity value at $2.2 billion (approximately 15.3 billion yuan), and GSK will obtain the global rights to ozureprubart outside of Greater China.This acquisition,It is an important move by GSK in its respiratory, immunology, and inflammation fields, and also marks GSK's official entry into the CSU treatment field, which has gained significant attention in recent years.In fact, since the second half of 2025, the CSU track has successively welcomed the first oral targeted drug and the first IL-4Rα inhibitor, making the treatment landscape increasingly diverse. Now, with the entry of GSK, this innovative competition surrounding allergic and immune diseases is further accelerating.GSK Enters the CSU Track, Changing the GameChronic Spontaneous Urticaria (CSU) is by no means a small indication. According to Novartis' official website, chronic spontaneous urticaria affects 1.7 million people in the United States, reaching 1/200 of the U.S. population. In China, the prevalence of chronic urticaria in the population is as high as 2.6%, with more than half being CSU.CSU is a severe skin condition characterized by itchy red wheals, often accompanied by deep tissue swelling (angioedema). Its course lasts at least six weeks with no identifiable external triggers. CSU symptoms are unpredictable and persistent, with hives and swelling potentially appearing on any part of the body, frequently disrupting sleep, social interactions, and daily activities, and may also lead to fatigue and anxiety.In the process of allergic inflammation, the elevation of immunoglobulin E (IgE) plays a key role, making it an ideal drug target for treating allergic diseases. Ozureprubart is a long-acting anti-immunoglobulin E (IgE) monoclonal antibody.So, where exactly does ozureprubart stand in the CSU treatment landscape?Currently, the first-line standard treatment for CSU still mainly involves antihistamines (such as cetirizine and ebastine), which relieve itching and swelling by blocking histamine H1 receptors.However, standard-dose H1 antihistamines can achieve complete symptom control in less than half of CSU patients.Against this backdrop, the introduction of biologics has provided a new direction for CSU treatment, and currently, CSU biologics are in the "oligopoly era" of omalizumab.Omalizumab is the world's first anti-IgE therapy, jointly developed by Novartis and Roche. It was launched in 2003 for the treatment of moderate to severe asthma and was not approved for CSU indication until 2014.Notably, the approval of the CSU indication in 2014 became a turning point for omalizumab's revenue. Its sales in 2013 were $1.611 billion, and after 2014, revenue continued to grow significantly, reaching $2.082 billion in 2015.Climbing to nearly 4.5 billion US dollars in 2024, becoming a real "blockbuster".In the Chinese market, omalizumab was approved in 2017 and entered the national medical insurance negotiation directory at the end of 2019. It has been approved for two indications: allergic asthma and chronic spontaneous urticaria. Data from Menet shows that in 2023, omalizumab sales in China's three major terminals and six major markets exceeded 700 million yuan, a year-on-year increase of 62.21%.Following omalizumab, the new generation of anti-IgE treatments focuses on optimizing potency and dosing regimens.Ligelizumab, a next-generation anti-IgE monoclonal antibody developed by Novartis, features higher selectivity and a different binding site. However, the drug failed to demonstrate superior efficacy compared to omalizumab in Phase III studies, and Novartis announced the termination of its development in 2023.In the Chinese market, pharmaceutical companies such as Tianchen Bio and Jimin Trust are also targeting the layout of a new generation of anti-IgE therapies.Among them, the core product of Tianchen Bio, LP-003, is currently the fastest-progressing next-generation anti-IgE antibody under research globally. In the Phase 2 clinical trial for treating CSU, it "head-to-head" defeated omalizumab. Its most advanced indication, allergic rhinitis, is currently in Phase 3 clinical trials, with plans to submit a product marketing application in 2026.Jemincare is associated with GSK's acquisition this time. Ozureprubart, under RAPT, was initially developed by Jiyu Pharmaceuticals, a subsidiary of Jemincare.In December 2024, Jiyu Pharmaceuticals sold the global rights outside of Greater China to RAPT for an upfront payment of $35 million.According to the RAPT official website, due to its extended half-life, ozureprubart has the potential to be administered every 8 to 12 weeks, whereas omalizumab is administered every 2 or 4 weeks.Notably, omalizumab's patent has expired in 2025, and currently, multiple biosimilar versions of omalizumab produced in China have been launched on the market. Among them, the injectable Omalizumab from Shiyao Group is the first biosimilar of omalizumab approved in China. It was approved for marketing in October 2024, indicated for adult and adolescent (12 years and above) patients with chronic spontaneous urticaria who still exhibit symptoms after treatment with H1 antihistamines.Not only is a new generation of anti-lgE treatment eyeing the market, but two major players will also enter the CSU arena in the second half of 2025 – Dupilumab, the new king of autoimmune treatments, and the BTK inhibitor Remibrutinib.Sanofi/Regeneron's IL-4Rα inhibitor Dupilumab expanded its indications to CSU in 2025, for the treatment of adolescents aged 12 years and older and adults with moderate-to-severe chronic spontaneous urticaria who have had an inadequate response to H1 antihistamines and have not received anti-immunoglobulin E therapy.The BTK inhibitor Remibrutinib is another key asset for Novartis in this field, expected to be approved by 2025 as the world's first oral targeted drug for the treatment of chronic spontaneous urticaria.In summary, against the backdrop of the successive emergence of new mechanism drugs such as the new generation of anti-IgE therapy, IL-4Rα inhibitors, and BTK inhibitors,The CSU track is moving from the "single blockbuster" era into a new phase of diversified and personalized treatment.Three Deals in a Day: Is GSK Stepping Up?This acquisition of RAPT marks an important step for GSK in expanding its immunology pipeline.GSK's main businesses are divided into three major segments: specialty medicines, vaccines, and general medicines. In 2024, due to a decline in its core vaccine business,GSK fell out of the top ten global pharmaceutical companies by revenue in 2024, ranking 12th with a revenue of $40.1 billion.Compared with the unsatisfactory performance of the vaccine and general medicine segments, the specialty medicine segment still maintains strong growth. In the first three quarters of 2025, its specialty medicines, vaccines, and general medicines generated revenues of £9.67 billion (+16%), £6.86 billion (+1%), and £7.52 billion (+1%), respectively.Specifically, its specialty drug segment includes HIV, Respiratory, Immunology & Inflammation (RI&I), and Oncology. In the first three quarters of 2025, revenues from its HIV, RI&I, and Oncology segments reached £5.54 billion (+10%), £2.72 billion (+17%), and £1.41 billion (+44%), respectively.RI&I is the second largest core business in GSK's specialty medicine segment, with current revenue in this field mainly coming from two products: Mepolizumab (Nucale) and Belimumab (Benlysta).Among them, Mepolizumab (Nucale) is the first monoclonal antibody targeting IL-5 launched by GSK in 2015. The drug was approved by the FDA in May 2025 for chronic obstructive pulmonary disease (COPD), and the approval of this indication will provide new growth momentum. In the first three quarters of 2025, Nucale generated revenue of 1.441 billion pounds, a year-on-year increase of 13%. Additionally, Belimumab, used to treat lupus erythematosus, is the first inhibitor acting on the B lymphocyte stimulator. The drug generated revenue of 1.26 billion pounds in the first three quarters of 2025, a year-on-year increase of 21%.Notably, depemokimab, a new product in the RI&I portfolio, was just launched in December 2025. As an ultra-long-acting anti-IL-5 monoclonal antibody, its peak sales are projected to exceed 4 billion pounds.In addition to the marketed products, the company is still advancing approximately 20 RI&I R&D pipelines. Among them, the new drug application for the IBAT inhibitor linerixibat was accepted by the FDA and EMA in June 2025 for the indication of treating cholestatic pruritus in adult patients with primary biliary cholangitis (PBC).On the same day as the layout of the RI&I sector, GSK made significant moves in the other two major sectors of specialty drugs, HIV and oncology.In the fastest-growing oncology business segment, Tesaro, a subsidiary of GSK, has reached an exclusive licensing agreement with South Korean biopharmaceutical company Alteogen to jointly develop a subcutaneous injection formulation of the PD-1 blocking antibody dostarlimab, in a collaboration worth up to $265 million.In the traditionally dominant HIV field, GSK, Pfizer, and Shionogi jointly announced the completion of an equity restructuring for their jointly established ViiV Healthcare. Shionogi paid $2.125 billion to acquire the 11.7% stake held by Pfizer.The simultaneous occurrence of BD transactions in the three major sectors of specialty drugs also aligns with the signals disclosed by GSK during the 2026 JPM conference. At the 2026 JPM conference,GSK Executives State Company is at Peak of R&D Execution, with Future Focus on HIV, RI&I, and Oncology, Alongside Increased Investment in Innovation and Business Expansion.In fact, in early 2026, GSK will usher in a "change of leadership," with its Chief Commercial Officer Luke Miels replacing Emma Walmsley, who has been at the helm for nine years, as the company's new Chief Executive Officer (CEO). Luke Miels has played a significant role in building GSK's specialty pharmaceuticals portfolio, particularly in the fields of oncology and respiratory diseases.The industry believes that this leadership change is GSK's proactive choice during a critical period of strategic transformation. It is reported that GSK's medium- and long-term goals are:Achieve total sales of £40 billion (approximately $53.6 billion) by 2031.This means that GSK must find a stronger growth engine in its innovative products and emerging pipeline.Moreover, GSK's intensive pipeline expansion during its leadership transition also reflects the strategic moves of global pharmaceutical giants under the pressure of the patent cliff and growth anxiety. They are actively strengthening their pipelines and planning for the future by in-licensing from external sources.Reference: "Guidelines for the Diagnosis and Treatment of Refractory Chronic Spontaneous Urticaria in China (2025 Edition)"
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