Guowei Pharma and Sino-American Shanghai Squibb Announce $76 Million Licensing Deal for AGT-Targeting siRNA Hypertension Drug GW906

On May 27, Chengdu Gowell Biopharmaceutical Co., Ltd. (hereinafter referred to as “Gowell Bio”) and Shenzhen Salubris Pharmaceuticals Co., Ltd. (hereinafter referred to as “Salubris”) jointly signed a new drug R&D cooperation agreement. Gowell Bio exclusively granted Salubris the rights related to the active pharmaceutical ingredient (API) and formulations of its investigational AGT-siRNA small interfering nucleic acid drug, GW906, in the Chinese market, including but not limited to R&D, registration, manufacturing, and commercialization. Joy Capital served as the exclusive financial advisor for this transaction.

Under the agreement, Chengdu Gowell Biopharmaceutical Co., Ltd. will receive upfront and R&D milestone payments totaling up to RMB 180 million. Following future product approval and commercial launch, cumulative sales milestone payments may reach up to RMB 370 million. Additionally, within the term of the agreement, Chengdu Gowell Biopharmaceutical Co., Ltd. will receive royalty payments based on a percentage of annual net sales.

GW906 is a small interfering RNA (siRNA) drug independently developed by Gowell Biopharmaceutical that targets angiotensinogen (AGT). It is being developed for the indication of primary hypertension and is currently undergoing Phase I clinical trials.

As the most upstream precursor protein of the renin-angiotensin-aldosterone system (RAAS), angiotensinogen (AGT) enables long-lasting blood pressure reduction when its synthesis is inhibited. GW906 targets AGT mRNA in the liver to effectively suppress AGT expression, thereby reducing angiotensin II production, leading to vasodilation and lowered blood pressure. Preclinical data demonstrate that GW906 has a favorable efficacy and safety profile, with potential for long-acting effects.

Hypertension is the most significant risk factor for cardiovascular disease, affecting a vast patient population that requires long-term, effective treatment and control. China has over 300 million hypertensive patients, yet both the treatment rate and control rate remain below 50%, indicating a substantial unmet medical need. Although traditional antihypertensive medications demonstrate certain efficacy, they have limitations in terms of long-term medication adherence and adverse reactions.

GW906, with its unique mechanism of action, targets AGT, the most upstream precursor in the RAAS system, and holds promise for addressing the issue of aldosterone escape associated with long-term oral administration of RAAS blockers (such as ACEIs and ARBs). Compared with ACE inhibitors, the AGT-siRNA drug GW906 does not lead to bradykinin accumulation, thereby potentially avoiding adverse reactions such as cough, angioedema, dyspnea, and pain.

Furthermore, GW906 is administered via intermittent subcutaneous injection, enabling long-term and stable blood pressure reduction, which is of significant importance for improving patient adherence.

Hypertension is a key therapeutic area for Salubris. Adhering to the principles of graded, staged, and classified diagnosis and treatment of hypertension, Salubris has developed a differentiated portfolio of innovative products—including monotherapies, fixed-dose combinations, co-crystal drugs, and small nucleic acid therapies—to address the clinical needs of patients with different types of hypertension. This portfolio includes Allisartan Isoproxil, Compound Allisartan Isoproxil Tablets, Xinchuotuo, SAL0108, SAL0120 (an endothelin receptor antagonist), and SAL0140 (an aldosterone synthase inhibitor), among others, demonstrating Salubris’ commitment to providing more precise and personalized comprehensive treatment solutions for patients.

Through its collaboration with Gowell Biopharmaceutical, Salubris has obtained exclusive licensing rights to GW906, an investigational AGT-siRNA innovative drug, further expanding the company’s innovative product pipeline in the cardiovascular and cerebrovascular fields.

Currently, the development of siRNA drugs targeting AGT remains in its early stages globally. If GW906 successfully gains marketing approval, it is poised to capture a niche market segment by leveraging its long-acting advantage, thereby offering hypertensive patients a novel and more convenient treatment option.

With the maturation of RNAi technology and breakthroughs in delivery systems, siRNA therapies are accelerating their expansion from the treatment of rare diseases into the broader field of chronic diseases.

siRNA is generally a double-stranded nucleic acid fragment with a length of 20–22 nucleotides. It leverages the endogenous post-transcriptional gene silencing mechanism within host cells to interfere with and downregulate the expression of corresponding proteins. Continuous advancements in chemical modification technologies have enabled siRNA therapeutics to achieve prolonged pharmacological effects, thereby reducing dosing frequency. This characteristic is particularly significant in the treatment of chronic diseases.

One of the most severe challenges in the treatment of chronic diseases is long-term medication adherence. Traditional small-molecule drugs mostly target downstream disease mechanisms and require daily dosing to maintain therapeutic blood concentrations, whereas patient non-adherence—such as missed doses, incorrect dosing, or self-discontinuation—is extremely common. siRNA therapeutics achieve long-lasting silencing of key targets (e.g., AGT), thereby blocking the production of pathogenic proteins at the source. With appropriate chemical modifications and delivery systems, their efficacy can last for weeks to months, enabling a “one-time administration, long-lasting effect” therapeutic outcome.

In the past, siRNA therapies were confined to the field of rare diseases, limiting their market potential. The approval of Novartis’s long-acting lipid-lowering drug, Inclisiran, broke this constraint. Leveraging its ultra-long-acting dosing advantage of “one injection every six months,” the drug saw its sales surge by nearly 63-fold over four years, successfully validating the therapeutic potential of siRNA therapies in chronic diseases.

Furthermore, Eli Lilly’s novel siRNA drug, lepodisiran, has achieved positive results in Phase II clinical trials: it can reduce Lp(a) levels by up to 93.9%, with the effects of a single dose lasting nearly one year. This ultra-long-acting “one-shot-per-year” profile has the potential to reshape the treatment paradigm for cardiovascular disease.

Numerous domestic pharmaceutical companies have also established robust siRNA drug pipelines, with indications primarily focused on hyperlipidemia, hypertension, and hepatitis B. The targeted molecules include PCSK9, ANGPTL3, AGT, and COX-2. According to incomplete statistics, approximately 10 domestically developed long-acting siRNA formulations have entered clinical development, including RBD7022 (licensed from Ribobio by Qilu Pharmaceutical), SGB-3403 (Shengyin Biotechnology), SYH2053 (CSPC Pharmaceutical Group), RP910 (Junshi Biosciences), and YKYY015 (Yuekang Pharmaceutical). Most of these candidates are currently in Phase I clinical trials.

In the field of AGT siRNA drug development, in addition to Gowell Biopharmaceutical, Bowang Pharmaceutical’s BW-00163, CSPC Pharmaceutical Group’s SYH2062, IBI3016 (SGB-3908) co-developed by Innovent Biologics and Shengyin Biologics, and HitGen’s LDR2402 have all entered the clinical trial stage.

As global R&D of siRNA drugs continues to advance and clinical data are progressively validated, siRNA therapeutics in the field of chronic diseases will enter a “Golden Age,” ushering in a broader market.

References:

The Eve of the siRNA Drug Boom: MNC Giants Hit “Crazy Acceleration” — YaoChuangXin