The Swiss antibody specialist Neurimmune and the German RNA biotech Ethris are collaborating to develop inhaled messenger RNA (mRNA) antibodies that can treat the catastrophic respiratory effects of coronavirus disease, also known as Covid-19.
The therapeutic mRNA would be delivered directly into the lungs of symptomatic patients via nebulizers with nanoparticle aerosols. The mRNA could then trigger the lungs to produce high local levels of antibodies that neutralize SARS-CoV-2, the coronavirus responsible for Covid-19.
In situ expression of these anti-SARS-CoV-2 antibodies would then act as an acute treatment for the 14% of infected patients reported to experience severe disease, including shortness of breath and hypoxia
The companies say they hope to begin clinical testing of their first candidate product in the last quarter of this year, depending on regulatory approval.
“To cure Covid-19, the virus has to be cleared systemically,” Ethris’ CEO, Gita Dittmar, explained to me. “This may eventually be achieved by the patients’ natural immune response against the virus, or, once developed, by systemic treatments against the virus.
“Our goal is to rapidly treat lung disease in patients with Covid-19 to gain time for systemic clearance of the virus and to reduce major lung complications.”
Dittmar said a significant advantage of mRNA-encoding antibody therapies was the speed with which they could move from lead antibody discovery to the production of a drug for clinical trials.
To develop the treatment, Neurimmune is currently identifying relevant antibodies from immune cells taken from recovered coronavirus patients. Ethris will then generate mRNA that can drive the expression of these antibodies directly in the lungs.
Dittmar pointed out that their vision was different to the preventative vaccine-based mRNA approach being developed by companies such as BioNTech, CureVac, and Moderna.
“We aim to develop a therapeutic for patients that are infected by SARS-CoV-2 and suffering,” she explained.
This antibody-encoding mRNA strategy is also being taken for a test drive in other indications by companies such as the US giant Moderna, which entered phase I for the treatment of the insect-borne disease chikungunya in February 2019. Additionally, a recent collaboration between the German mRNA company CureVac and the Danish antibody developer Genmab aims to develop cancer treatments using similar mRNA technology.
While acknowledging the newness of the field and that there are no approved mRNA therapies yet, Dittmar said that a number of vaccines and treatments were moving through clinical evaluation in the EU and US and had demonstrated safety as well as initial signs of efficacy.
Other companies are using different approaches in an attempt to tackle coronavirus, including antiviral therapy, virus-neutralizing antibodies, virus-neutralizing RNA, and anti-inflammatory treatments.
Dittmar said: “In the current situation, it is very important that many different treatment approaches be developed in parallel and tested clinically so that we rapidly reach a range of therapeutic approaches. Some of these treatments may even be useful in combination.”