AstraZeneca has expanded its respiratory portfolio with the addition of an inhalable drug that may compete with Merck’s recently approved treatment for chronic obstructive pulmonary disease (COPD).
The drug, TQC721, originates from Sino Biopharmaceutical, based in Hong Kong. On July 8, the developer announced that AstraZeneca had agreed to pay $200 million in an upfront fee to one of its subsidiaries for the rights to this clinical-stage asset.
TQC721 is a small molecule that employs a dual mechanism: PDE3 inhibition expands airways, while PDE4 inhibition tackles inflammation. This approach mirrors that of Merck’s Ohtuvayre, an inhalable medication delivered via nebulizer. In 2024, Ohtuvayre became the first PDE3/4 inhibitor approved by the FDA for COPD. Last year, Merck added Ohtuvayre to its portfolio through a $10 billion acquisition of its developer, Verona Pharma. Merck has reported $178 million in sales for Ohtuvayre for 2025, with the product generating $131 million in revenue for the first quarter of this year.
Sino describes the TQC721 inhibitor as potentially the best PDE3/4 blocker in its class, offering balanced inhibition of both targets. Alongside a nebulized formulation, the company is developing a dry powder inhaler version. They assert that both formulations provide a wide range of products to target different patient segments, disease severities, and commercial contexts. The nebulized formulation is currently in Phase 3 trials in China, while the dry powder inhaler is in Phase 2.
Respiratory and immunology are AstraZeneca’s third-largest therapeutic areas by revenue. The company’s leading respiratory product, Symbicort, which is an inhalable combination drug approved for asthma and COPD, generated over $2.8 billion in revenue last year. Although its patents have expired, AstraZeneca retains patents on the inhaler for this medication. With several other respiratory product patents having either expired or set to expire in the coming years, AstraZeneca has invested in its respiratory drug pipeline.
The internally discovered tozorakimab, an antibody targeting IL-33, showed preliminary results in April indicating it achieved its primary endpoint in a Phase 3 clinical trial for COPD. Tezspire, an antibody blocking TSLP approved for asthma treatment, is undergoing advanced clinical trials for COPD. Nevertheless, AstraZeneca faced setbacks with COPD treatment; Fasenra, an antibody initially approved for asthma, reported disappointing Phase 3 results in COPD last September. Although the data indicated numerical improvement, it was insufficient to meet the primary endpoint of reducing COPD exacerbations compared to a placebo. AstraZeneca’s COPD R&D efforts also include small molecules such as AZD6793, an IRAK4 inhibitor that is currently midway through clinical testing.
AstraZeneca’s agreement with Sino grants it global rights to TQC721, excluding China. The pharmaceutical company also has rights to certain unspecified future development programs. The inhibition of PDE3 and PDE4 has potential applications in other respiratory disorders. For instance, Merck is evaluating Ohtuvayre for the treatment of non-cystic fibrosis bronchiectasis. Should AstraZeneca’s research on TQC721 achieve significant milestones, Sino could receive up to $1.9 billion in milestone payments, in addition to royalties on sales of approved drugs.
Illustration: CIPhotos, via Getty Images
