Company officials enter the headquarters of NorthStar Medical Radioisotopes, a Beloit radioisotope producer and supplier. The company announced that it and a Chicago company plan to develop new drugs to treat patients with severe symptoms of COVID-19.


Beloit’s NorthStar Medical Radioisotopes is partnering with a Chicago pharmaceutical company on medicines that could treat patients with life-threatening symptoms of COVID-19.

NorthStar and Monopar Therapeutics announced Tuesday that they plan to develop hybrid medicines that pair antibodies with medical radioisotopes. The drugs would target and destroy a type of rogue human immune cell that is thought to cause severe lung and organ inflammation in some people with COVID-19, the disease caused by the novel coronavirus.

Jim Harvey, NorthStar’s chief science officer, said the two companies have filed for patents for drugs they believe could destroy cytokines, protein-based immune cells that can overtake the bodies of patients with weakened immune systems.

In response to COVID-19, those patients’ immune systems appear to create “cytokine storms,” in which legions of rogue cells attack healthy body cells instead of the virus causing the infection.

Harvey said drugs that pair antibodies with radioisotopes have been used for more than two decades in treatments that target and destroy certain body cells. But the drugs NorthStar and Monopar seek to develop would be designed specifically to invade cytokine cells.

“We’re taking an antibody and we’re putting a therapeutic radionuclide on that antibody to target those really, really sick patients,” Harvey said. “These are the ones that are unable to fight infection on their own, the 15% of people that end up in the intensive care beds around the world and around the country.

“If you look at that same population, that 15% is where the vast majority of the (COVID-19) deaths are coming from. These are the people that need a treatment.”

The two parts of the drug would act in tandem to locate rogue immune cells, get inside them and destroy them, Harvey said.

NorthStar is among the first companies in the U.S. to launch domestic production and distribution of medical radioisotopes used in medical testing. The new partnership with Monopar comes as the pharmaceutical industry scrambles to develop vaccines for COVID-19, which is reported to have killed about 114,000 people in the U.S. since February.

Harvey said NorthStar believes a parallel course—the development of a treatment—is needed because it could take time, perhaps a few years or longer, before workable vaccines are created and approved for use.

In the meantime, people will continue to get infected with COVID-19 or other strains of coronavirus.

“This is not a vaccine,” he said. “We’re working toward a true therapeutic because, regardless of how many different vaccines might come on the market that could be successful, there will always be these types of inflammatory respiratory diseases that don’t respond to vaccines. COVID-19 just happens to be the current one that everyone’s so familiar with, but it’s causing so many deaths.”

Chandler Robinson, CEO of Monopar, said the two companies first must determine which medical antibodies could pair best with radioisotopes. Harvey said part of the task, too, will be to find out which type of radioisotope—and what dosage—will be effective in stemming the damaging immune response caused by cytokine storms.

Harvey said it’s too early to lay out a timeline for a new COVID-19 treatment because it would face the same regulatory hurdles as any new drug.

“There will be some development work. There will be some clinical trials. There will be an evaluation by the FDA and necessary trial results before there’s an approval,” Harvey said.

“You can’t predict how long the FDA will review that type of an application. They could come back and say, ‘This is absolutely beautiful, stamp of approval,’ or they could come back and say, ‘We need some more data.’ But we hope that we’re speaking in terms of a very short number of years.”