1 Incubation in Nantes
Head of the infectious and tropical diseases department at Nantes University Hospital, Prof. François Raffi is chasing time. Just like Dr. Benjamin Gaborit, a 36-year-old infectious disease specialist, who has been coordinating with him, since the summer of 2020, an unprecedented clinical trial. The aim is to test Xav-19, this new generation molecule designed by the Nantes start-up Xenothera. It would block the multiplication of the covid-19 virus and would become, if it works, a reference drug in the treatment of the disease. Phase 2B of the Polycor clinical trial started on Monday January 11, following the green light from the National Medicines Safety Agency (ANSM) at the end of December 2020. 400 patients from around 40 French hospitals, including six in the Great West, should quickly integrate this protocol, coordinated by the Nantes University Hospital. Rennes, Vannes and Quimper are already there. Five administrations of the test dose took place last week, including three in Nantes.
“Faced with the health crisis, the challenge is to participate in the war effort”
2 “A happy combination of circumstances”
“All this is linked to a happy combination of circumstances,” recalls Professor Raffi. In March 2020, the young company Xenothera, also from Nantes, approached us saying that it was developing specific polyclonal antibodies, different from already existing industrial products against coronaviruses. Apart from respiratory supportive care, we were at a loss for the care of the first patients with covid-19. The management of the CHU validated the partnership. We took this opportunity to propose a coherent scientific project to evaluate this molecule. Faced with the health crisis, the challenge is to participate in the war effort ”.
3 The first conclusive phase
The drug candidate Xav-19 was tested on 18 first patients (14 in Nantes), from September to December 2020. “It was administered for serious forms of covid-19, on patients hospitalized in infectious disease departments, pneumology or geriatrics, rather outside intensive care, ”says the team. Different schedules and doses were studied, in a “randomized” manner (with half of placebos, in physiological serum). “There was no hypersensitivity or allergy. It was also possible to verify that the high dose of Xav-19 significantly and lastingly increased the antibody concentrations in the patient. It’s encouraging, ”says Prof Raffi. The second phase can now begin on a larger scale. “Always according to the same criteria, excluding minors, pregnant women or people over 85 years old. Increasing the number will allow us to multiply the profiles and standardize the results, explains Dr Gaborit. The aim is for the worsening of symptoms to be stopped until the fifteenth day after taking the candidate drug ”.
“At the Nantes University Hospital, we have already carried out numerous tests in partnership with laboratories. But clinical application has never gone so far ”.
4 National research priority
This unprecedented consortium between a private company (Xenothera), public university hospitals, virology and immunology laboratories, a faculty and researchers, figures in the 15 clinical studies on covid-19 labeled “national research priority” by the government. “It is the only one that brings together so many people, with a new therapeutic avenue,” applauds Professor Raffi. “At Nantes University Hospital, we have already carried out numerous tests in partnership with laboratories, there is a long-standing culture of research and innovation,” confirms Dr Gaborit. But clinical application has never gone so far ”.
5 “It’s not just vaccination”
If all eyes are now on the start of vaccination, Professor Raffi recalls the importance of developing, in parallel, a therapy. “First, because prevention and treatment are two complementary axes in the fight against disease. Secondly, because even the most effective vaccine is only 95% effective. we must be able to treat the 5% who will have a covid, despite everything ”.
6 And after?
“The challenge is to be fast, efficient and relevant”, notes Dr Gaborit, who hopes for a possible conclusion “by the summer of 2021”. What if Xav-19 turns out to be disappointing? “We are experimenting with a new technology never before applied to humans. She will provide us with any leads, whether for covid-19 or for other treatments ”.