A German trial finds that azelastine nasal spray, a common hay fever treatment, reduces SARS-CoV-2 and rhinovirus infections. Could this cheap, accessible spray be a new tool against respiratory diseases
German study finds hay fever medication lowers risk of SARS-CoV-2 and other respiratory viruses
A common hay fever nasal spray may help protect against COVID-19, according to a new clinical trial led by Professor Robert Bals, Director of Internal Medicine V at Saarland University Medical Center.
The randomized, double-blind Phase 2 trial, known as CONTAIN, tested the antihistamine azelastine nasal spray on 450 participants over 56 days. Half of the participants (227) received azelastine three times daily, while the control group (223) used a placebo spray.
The results were striking:
- 2.2% of the azelastine group tested positive for SARS-CoV-2
- 6.7% of the placebo group tested positive three times higher
- All infections were confirmed with PCR tests
“These findings show that azelastine significantly reduced the risk of coronavirus infection,” said Professor Bals. “This is the first clinical trial to demonstrate a protective effect in real-world conditions.”
Beyond COVID-19: Protection Against Other Viruses
The study also revealed unexpected benefits:
- Participants using azelastine had fewer symptomatic COVID-19 cases
- They reported a lower overall number of respiratory infections
- The treatment group had a reduced incidence of rhinovirus infections (1.8% vs. 6.3%), a major cause of the common cold
Azelastine has been available for decades as an over-the-counter treatment for hay fever, but earlier laboratory studies suggested antiviral activity against SARS-CoV-2 and other respiratory viruses.
A Potential New Layer of Protection
According to Professor Bals, azelastine could serve as an accessible preventive tool, especially for high-risk groups during infection surges or before travel.
“Azelastine nasal spray could provide an additional, easily accessible prophylactic to complement existing protective measures,” said Bals. “However, larger, multicentre trials are needed to confirm these results and explore its effectiveness against other respiratory pathogens.”
Collaboration Behind the Breakthrough
The trial was a collaborative effort involving:
- The Institute of Clinical Pharmacy (Professor Thorsten Lehr, Dr. Dominik Selzer)
- The Institute of Virology (Professor Sigrun Smola)
- The pharmaceutical company URSAPHARM Arzneimittel GmbH, which sponsored and manufactured the investigational product
- The Helmholtz Institute for Pharmaceutical Research Saarland (HIPS)
The project is being hailed as a model of academic, industrial, and public health cooperation in the Saarland region.
Why It Matters
If confirmed in larger studies, azelastine could provide a simple, low-cost preventive option to reduce COVID-19 spread and other viral respiratory illnesses without needing to develop new drugs from scratch.
