A poison capable of killing in a few days from a simple seed of a common plant: ricin fascinates experts as much as it worries them. Subtle, invisible, it leaves doctors little time when it penetrates deep into the lungs. Until now, no targeted treatment existed.
However, France has just reached a strategic milestone. On January 12, the government announced the marketing of Ricimed, the first antidote against ricin, designed by the Lyon SME Fabentech, specializing in immunotherapies against biological threats. It remains to be understood what this really changes.
Ricin: the poison of a common plant which raises fears of an attack
Extracted from the seeds of the castor plant, a widely cultivated plant, ricin is formidable when inhaled. Inserm recalls that it “quickly reaches the lungs, then the alveoli. From there, it destroys the host cells and successively causes pulmonary edema, acute respiratory failure, then death within a few days.“.
The Orphanet website summarizes a rare but extremely serious poisoning. “Early signs and symptoms are nausea, vomiting, diarrhea, hematemesis and melena (if ingested), cough, wheezing, dyspnea, sore throat and congestion (if inhaled), and erythema, induration, blisters, capillary leak syndrome and localized necrosis (if injected). Signs and symptoms may progress to seizures, shock, organ failure, pulmonary edema and respiratory failure“.
Ricimed, the French antidote against ricin presented as a feat
The marketing of Ricimed marks a political as well as a scientific step. A “technological feat”, assures the State. “This is a world first in a key area for national sovereignty“, greets the government, which recalls that ricin is considered a “bioterrorist” threat.
To achieve this, the State supported the Lyon SME Fabentech. “cThis success is thus the fruit of the joint mobilization of public and private, military and health actors, which confirms France’s pioneering position in the field of biotherapies.“, insist ministers Catherine Vautrin and Stéphanie Rist in a joint press release. French stocks already exist and the company is preparing export deliveries.
From military laboratories to Fabentech: a decade of research against ricin
The Armed Forces Biomedical Research Institute has developed a monoclonal antibody against ricin and asked the Inserm laboratory in Tours to create a suitable aerosol. “Aerosolization stresses antibodies, which become denatured and may lose function or be poorly tolerated due to aggregate formation“, clarifies Nathalie Heuzé-Vourc’h in an Inserm article. “Every detail had to be specific to the product and was designed for effective deposition in the alveoli: the size of the droplets, their number, the technology of the aerosol generator, the composition of the antibody, etc.“, she explains, after tests where 100% of poisoned animals were saved up to six hours after exposure.
This journey, from the first antibodies tested in animals to the authorized drug, illustrates an assumed strategy of sovereignty in the face of biological threats. For health and military authorities, having a specific antidote against ricin in France now changes the scale of preparation for a possible attack.