A patient who recovered from COVID-19 donates convalescent plasma in Missouri in 2020. New research suggests plasma could best help patients if given early. (Michael B. Thomas, TNS/The Minnesota Star Tribune)

COVID-19's omicron variant spelled trouble in multiple ways.

It is highly transmissible. It weakened vaccines' defense against infection, though the shots still confer strong protection against severe illness. In addition, two of three widely used monoclonal antibody treatments for those infected with it are essentially ineffective.

The virus's ability to surprise requires a medical arsenal that adapts nimbly as well. Given that, it's time for the World Health Organization (WHO) and other officials to take a fresh look at a historic infectious disease treatment — convalescent plasma.

Minnesota's political leaders could — and should — should join the call for re-evaluation.

In 2020, Sen. Amy Klobuchar, D-Minn., introduced legislation to raise awareness of convalescent plasma's importance. In 2022, this high-profile senator and one-time presidential candidate has an opportunity to act again, this time by aiding physicians at Johns Hopkins, Mayo Clinic and the University of Minnesota.

Doctors from these medical centers are urging health officials to consider and smooth the way for this naturally generated therapy to play a different role in treating COVID.

During the early pandemic, it was given to the very sickest patients in the hospital. While research ultimately didn't support that use, there is solid new data from Johns Hopkins-led researchers backing its value in early treatment. Like the monoclonal antibodies, convalescent plasma could be given promptly to reduce the risk of hospitalization.

A letter from Klobuchar and others to key agencies could spotlight this new research. It could also help address a bureaucratic snag contributing to a supply bottleneck.

Convalescent plasma has a long history helping combat disease. Before there were antibiotics and antivirals, physicians recognized that recovering patients could help others from becoming seriously ill. The reason: the antibodies they naturally manufactured.

Blood donated by these patients can be "processed to remove blood cells, leaving behind liquid (plasma) and antibodies,'' according to the Mayo Clinic. The antibodies can then be infused into the newly ill. It's like having a seasoned platoon show up to assist immune system soldiers.

Doctors like Mayo's Dr. Michael Joyner were on the front lines in researching this treatment against COVID-19. Their work inspired hope early in the pandemic before vaccines.

The WHO recently reviewed pooled research data on the therapy's effectiveness in treating COVID. On Dec. 7, it updated its guidelines, recommending against its use, but said clinical trials should continue for severely ill patients.

But on Dec. 21, Johns Hopkins-led researchers posted their findings from a multicenter trial involving 1,181 patients. Unlike many other studies, they were given concentrated convalescent plasma early, not when seriously ill. The research, posted to the preprint website MedRxiv, found:

"With early administration of high-titer SARS-CoV-2 convalescent plasma reducing outpatient hospitalizations by more than 50%, our findings suggest that this is another effective treatment for COVID-19 with the advantages being low cost, wide availability and rapid resilience to the evolving SARS-CoV-2," Johns Hopkins researcher Dr. Kelly Gebo stated.

Dr. Claudia Cohn, a University of Minnesota Medical School professor and transfusion medicine researcher, called the new findings "really good strong data." She said it would be helpful for leaders in Washington, D.C., to ask questions about the new findings and how to boost plasma supplies.

A spotlight is especially needed on foot-dragging by the U.S. Centers for Medicare and Medicaid Services. It has yet to set a reimbursement policy for outpatient treatment with convalescent plasma despite a recent plea by three leading blood banking organizations. Doing so could help spur blood banks to collect more plasma.

A Klobuchar spokeswoman lauded the scientific community's "remarkable work" and said the senator believes "regulatory agencies should vet new treatments with urgency and make them available to the public as soon as scientific evidence shows it is safe to do so."

We hope Minnesota's senior senator and others heed this call for help from leading medical researchers. This promising treatment deserves another look.