Antibody therapy promoted amid Minnesota COVID-19 spike, 2,553 new infections

State health officials are promoting an underutilized outpatient therapy amid rising pandemic activity in Minnesota, which has reported 6,864 deaths from COVID-19 and 524,203 infections with the coronavirus that causes the respiratory disease.

The totals include four deaths reported Friday by the Minnesota Department of Health along with 2,553 diagnosed infections — the highest single-day case count since Jan. 4. The number of Minnesota hospital inpatient beds filled with COVID-19 cases increased on Thursday to 439 — including 112 cases requiring intensive care.

Minnesota has a supply of 9,000 doses of synthetic monoclonal antibodies and can conduct 2,000 infusion therapies per week, but people haven't taken advantage of this outpatient therapy that can prevent hospitalizations and severe COVID-19, said Dr. Ruth Lynfield, state epidemiologist.

"The drug may prevent the need for hospitalization in people who have risk factors for severe disease, but must be given early in the course of COVID-19 — within 10 days of the onset of symptoms, sooner if possible," Lynfield said.

Three monoclonal antibody therapies, which mimic the body's natural virus-fighting capabilities, have received federal emergency use approval since November. Their uptake was slowed by greater promotion of COVID-19 vaccines and some questions about whether they worked against certain variant strains of the virus that causes COVID-19, but Lynfield said they could play a valuable role against the latest increase in pandemic activity.

Minnesota's positivity rate of COVID-19 diagnostic testing increased to 5.5% and remains above the 5% caution threshold that suggests broad viral spread in the state. The rate was only 3.5% on March 1.

On the encouraging side, the state on Friday reported that 1,720,811 people 16 and older have received at least a first dose of COVID-19 vaccine and 1,088,332 of them have completed the one- or two-dose series. The number who have received at least a first dose constitutes 39% of the 4.4 million Minnesotans 16 and older and almost 82% of the state's senior citizens.

COVID-19 death numbers are typically higher on Fridays because of the increased reporting and verification of death records that occurs later in the workweek. Friday's total of four deaths is the lowest in months, underscoring hopes among state health officials that vaccination progress will reduce the level of severe COVID-19 caused by the latest increase in infections. Reporting also can be artificially lower entering a holiday weekend.

Even if they are under­utilized, monoclonal antibodies could be contributing to Minnesota's improving COVID-19 outcomes as well, said JP Leider, a University of Minnesota public health researcher and a coordinator of the Minnesota Resource Allocation Platform, which oversees the equitable distribution of these therapies.

"There's a ton in reserve, which is great," Leider said. "I just wish it would get used to help more folks — especially if this surge keeps up."

Federal approval was granted for three monoclonal antibody products — bamlanivimab; a combination of bamlanivimab and etesevimab; and a combination of casirivimab and imdevimab — with data showing they reduced hospitalizations from 15% of COVID-19 cases to less than 4%.

Of 4,620 recipients of the therapies in Minnesota, 104 have later been hospitalized for COVID-19 — a rate of 2.3%.

Genomic sampling of roughly 5% of all positive COVID-19 test samples in Minnesota suggests that B.1.1.7 is now responsible for more than half of new infections in the state.