Sirius Therapeutics Files for Hong Kong IPO: Reports H1 Profit Despite No Commercial Revenue

Another small nucleic acid therapy company plans to list on the Hong Kong Stock Exchange.

On September 28, Sirius Therapeutics submitted an IPO application to the Hong Kong Stock Exchange, with Goldman Sachs, Haitong International, and HSBC as joint sponsors. Founded in 2021 by OrbiMed Entities and Creacion Ventures, Sirius Therapeutics currently operates dual headquarters in San Diego and Shanghai, primarily focusing on the siRNA (small nucleic acid) field.

Sirius Therapeutics' core product, SRSD107, is a potential first-in-class siRNA drug targeting coagulation factor XI, currently in Phase II clinical research. In September 2025, the company completed the dosing of the first subject in the Phase II clinical trial of its core product SRSD107 in Europe.

It is also relying on the aforementioned core product that, in May this year, Sirius Therapeutics reached a cooperation agreement with CRISPR Therapeutics (CRSP), a Nasdaq-listed pharmaceutical company, to achieve a 50:50 global economic interest and co-development of SRSD107. According to the agreement, Sirius Therapeutics received $25 million in cash and CRSP stocks worth approximately $70 million in advance, and is eligible for milestone payments exceeding $800 million, with a total amount close to $900 million.

siRNA offers a highly targeted, potent, and long-lasting method to treat diseases at their genetic source. According to a Frost & Sullivan report, the global siRNA therapy market size will reach $2.4 billion in 2024 and is expected to grow to $50.3 billion by 2040, with a compound annual growth rate (CAGR) of 20.9%.

In the field of small nucleic acid therapy, the most representative product is Novartis' Inclisiran sodium injection. This drug belongs to a long-acting siRNA therapy targeting PCSK9, which can reduce low-density lipoprotein cholesterol with just two injections per year. In the first half of 2025, the drug generated $555 million in revenue for Novartis, marking a 66% year-over-year increase, and it is expected to become Novartis' next blockbuster product.

In China, a number of pharmaceutical companies have also entered the small nucleic acid therapy sector. In April this year, Suzhou Ribo Life Science Co., Ltd. ("Ribo Life Science") also submitted an application to the Hong Kong Stock Exchange. In January 2024, Ribo Life Science reached a BD deal with the well-known multinational pharmaceutical company Boehringer Ingelheim (BI), with a total transaction value exceeding 2 billion US dollars.

Overall, the R&D pipeline layout of Sirius Therapeutics covers three major areas: coagulation disorders, cardiometabolic diseases, and obesity. Most of the targets have not been disclosed. In addition to SRSD107, there is also SRSD216, a potential best-in-class siRNA targeting Lp(a), which is currently in Phase 2a trials simultaneously in China and the United States. Furthermore, SRSD384 is an INHBE-targeting drug candidate for obesity, for which an IND (Investigational New Drug) application is being actively advanced.

At the performance level, Sirius Therapeutics has not generated any revenue or cost of sales. In 2023 and 2024, the company's losses for the period were RMB 309 million and RMB 342 million, respectively. In the first half of 2025, the company reported a profit of RMB 34.461 million, compared to a loss of RMB 159 million in the same period last year. The main reason for turning losses into profits was that Sirius Therapeutics received non-recurring gains such as fair value gains from CRISPR shares in its collaboration with CRISPR. According to the prospectus, the company’s other income and gains increased from RMB 4.5 million in 2024 to RMB 144 million in the same period in 2025, primarily due to a RMB 140.2 million increase in fair value gains on financial assets measured at fair value through profit or loss, reflecting the fair value changes of CRISPR shares received when the company obtained upfront payments from its collaboration with CRISPR.

In terms of cash flow, the net cash used in operating activities was RMB 209 million and RMB 180 million in 2023 and 2024, respectively. As of June 30, 2025, the net cash generated from operating activities was RMB 98 million.

The proceeds from this Hong Kong stock listing will be used for the research and development of Sirius Therapeutics' core product SRSD107, key product SRSD216, key product SRSD384, pipeline projects including extrhepatic programs, as well as for working capital and business development purposes.

Controlling Shareholders: OrbiMed entities are the controlling shareholders of Sirius Therapeutics. Specifically, OrbiMed Asia and OrbiMed U.S. hold approximately 20.23% of the company's total issued share capital, respectively. The prospectus shows that OrbiMed entities invest in the global healthcare industry, ranging from seed-stage venture capital to large publicly traded companies.

Junqun Ji, 62, holds 5.87% of the equity in Sirius Therapeutics and serves as the company's executive director and chief executive officer. The prospectus shows that Junqun Ji has nearly 30 years of experience in the fields of drug discovery and translational medicine. Before joining Sirius Therapeutics, he served asWuXi AppTecVice President and Head of Oncology and Immunology. Previously, he also served as the Head of AstraZeneca Biosciences and Director of Translational Medicine for Asia and Emerging Markets.