Human trials to commence using SARS-CoV-2 antibodies from cow's blood

By Angela Betsaida B. Laguipo, BSNJun 19 2020

The coronavirus pandemic has sparked a sense of urgency as it actively spreads across the globe. The number of reported cases has now surpassed 8.46 million people, with a death toll of more than 453,000. Scientists and pharmaceutical companies are racing to develop an effective treatment and vaccine against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Now, a South Dakota biopharmaceutical company is developing an antibody treatment for the novel coronavirus using cow’s blood. Based in Sioux Falls, SAb Biotherapeutics has injected genetically engineered cows with a non-infectious part of the novel coronavirus, which causes COVID-19. In turn, the cows produce natural antibodies against the contagion.

Genetically engineered cows are making human antibodies that neutralize SARS-CoV-2. Image Credit: SAb Biotherapeutics

Producing natural antibodies

The cows have been given genes from the human immune system that makes antibodies. They are injected with a specific amount of the non-infectious parts of the novel coronavirus, enough to trigger the production of antibodies to fight off the infection. Further, they will produce a specifically targeted high-neutralizing antibody that is hoped can be used in COVID-19 patients.

The scientists used cows because the antibodies circulate in their plasma, and they have between 30 and 45 liters of plasma each month from each animal.

SAb’s therapeutic candidate, SAB-185, is a new immunotherapy generated from the company’s propriety technology, the DiversitAbTM platform, which aims to produce fully human polyclonal antibodies that target SARS-CoV-2.

The company has the unique capability to produce fully human polyclonal antibodies without the need for human donors.

“SAB has developed a unique system to naturally, rapidly, and consistently produce large amounts of targeted human antibodies without human donors, as we have done with MERS and Ebola,” Eddie Sullivan, SAB Biotherapeutics president, CEO, and co-founder said.

“Our targeted high-potency immunotherapies leverage the natural immune response, thereby providing a highly-specific match against the complexity, diversity, and mutation of a disease. We have data in other indications demonstrating that our therapies are much more potent than those produced from convalescent plasma from recovered patients and data showing SAB’s therapies remain effective when other therapeutics may develop resistance,” he added.

Efficacy tests

The scientists said they have already shown the same concept can work for the Middle East Respiratory Syndrome (MERS), a disease caused by a virus akin to the one that causes COVID-19.

Dr. Sullivan said that whether the antibodies will work against SARS-CoV-2 still has to be shown. To do that, the team partnered with William Klimstra at the University of Pittsburgh. The scientists plan to show that the antibodies will not cause more problems than they solve; hence, there is a need for human trials.

The team also plans to conduct efficacy tests to show whether the antibodies prevent disease in animals exposed to the coronavirus. They will look at virus production, signs of infection, weight loss, and other potential side effects to evaluate how sick the cows will get.

SAB-185 is the resulting drug generated from the antibodies produced by the genetically modified cows. It is expected to begin human trials next month, but the company has not revealed how many people will be recruited for the clinical trials and how long they would take.

If the human trials are successful, the new therapy could potentially treat people who are severely ill because of COVID-19. It could also provide protective antibodies for high-risk populations, such as front-liners, mission-critical staff, the elderly, and those with underlying medical conditions.

“The current pandemic is shining a light on the direct need for new and innovative therapies in addition to being prepared to react quickly for global health security,” Sullivan said.

“This initiative is solidifying a place for targeted human polyclonal antibodies in the immunotherapy space, showcasing the power of the native human biological immune response,” added Sullivan. “More importantly, we’re providing an innovative solution, to address COVID-19 and be responsive to future emerging threats,” he added.