Sanofi has backed Altesa BioSciences in a US$75m series B round for the rhinovirus-focused biotech led by former acting FDA commissioner Brett Giroir.
The funding will mainly support a phase 2b study, a mid-stage clinical trial, of vapendavir, an oral antiviral pill for patients with chronic obstructive pulmonary disease (COPD), a long-term lung condition that makes breathing difficult.
Vapendavir was originally developed by Aviragen for the common cold but missed its primary endpoint, the trial’s main goal, in a phase 2b trial in asthmatic patients with rhinovirus in 2017.
Giroir said: “We are honoured to have Forbion as our lead investor, a global leader with an unmatched track record for developing companies and products across multiple therapeutic areas.
“In addition, Altesa will benefit greatly from the participation of Sanofi, given its ongoing expertise in COPD therapeutics.
“By focusing on the true medical need, patients most at risk for hospitalisation, death, and long-term decline, we hope to radically improve outcomes and reduce overall healthcare burden.”
Altesa in-licensed the broad-spectrum antiviral and is developing it in COPD.
The latest study will build on a trial last year of 40 COPD patients, where Altesa said it saw improved upper and lower airway symptoms, reduced illness durations and lower inflammatory markers, which are signs of inflammation in the body.
At that stage, the company said vapendavir, taken as a pill, was the only direct-acting antiviral targeting rhinovirus in human clinical trials.
The planned study aims to enrol 900 COPD patients in the US and UK, who will be randomised when they experience rhinovirus infection.
Rhinovirus is the most common cause of respiratory flare-ups in patients with COPD and other chronic lung diseases.
The trial is expected to begin in the second quarter and will be overseen by chief medical officer Katharine Knobil, who joined Altesa in May 2025 and previously held the same role at GSK.
Altesa was founded in 2022 with US$4m in seed funding to build on the work of Emory University scientists behind Merck & Co.’s Covid-19 antiviral molnupiravir and a billion-dollar HIV treatment.
The oversubscribed series B was led by Forbion, with previous investors Medicxi, Pitango and Atlantic Partners returning alongside Sanofi.
Knobil said: “Our trial’s objective is to demonstrate that treatment of rhinovirus respiratory infections can improve symptoms, hasten resolution of illness, and maintain quality of life, while potentially avoiding advanced medical interventions.
“For many COPD patients, even a simple cold can lead to an exacerbation, hospitalisation, and worsening quality of life, vapendavir has the potential to change that trajectory.”
Beyond COPD, Altesa hopes to apply vapendavir to other high-risk respiratory populations, such as patients with asthma.
