When a surge of new COVID-19 patients three months ago strained the University of Pittsburgh Medical Center’s ability to give monoclonal antibodies intravenously, the health system tried a different way to give the drug that it says has proven to be easier and just as effective.

In a new study, which has not yet been peer-reviewed, researchers from UPMC and the University of Pittsburgh School of Medicine report that giving monoclonal antibodies by a series of four injections under the skin instead of IV infusion can help busy hospitals effectively treat more people, because a wider array of employees can give shots and injections are quicker.

Only nurses with special training in placing intravenous lines can give infusions, but more nurses, pharmacists and pharmacy interns can give shots, said Erin McCreary, an infectious diseases pharmacist at UPMC and lead author of the study. Giving monoclonal antibodies by injection allowed her health system to more than double outpatient appointments for the treatment.

UPMC said this is the first study to examine different methods of giving monoclonal antibodies. It was published this month in medRxiv, a preprint journal.

The drugs received emergency approval for IV use, but the FDA said the cocktail made by Regeneron can be given by injection when infusion is “not feasible and would lead to delay in treatment,” UPMC said. In clinical trials, the Regeneron treatment was given only by infusion.

The drug is most effective when given early in the course of a patient’s disease — no later than 10 days after symptoms appear. McCreary said that increased demand after Labor Day meant that many patients would face delays or would not get monoclonal antibodies at all. So UPMC switched to monoclonal antibody injections at most of its outpatient infusion centers from Sept. 9 to Oct. 26. The centers then returned to IV administration when possible. Injection and infusion patients received the same dose, McCreary said.

The switch to injections allowed UPMC to increase appointments for monoclonal antibody treatment from 400 to 1,000 patients a week with the same number of staff, the study said.

Demand for monoclonal antibodies is still high, McCreary said, and UPMC is still using injections as the country experiences a wave of infections from the delta variant. The system is now averaging about 300 referrals for monoclonal antibodies a day. “For the past three or four weeks, every week has broken our record,” she said.

The researchers compared three groups of patients: 969 who received injections, 1,216 who received infusions and 4,353 similar patients who were not treated. They measured hospitalizations and deaths for 28 days.

COVID-19 patients who received subcutaneous injections had a 3.4% chance of being hospitalized or dying compared to 7.8% for the untreated patients. The odds were slightly better for patients who received IV monoclonal antibodies, but that difference was not statistically significant. “There was a slight difference that we don’t think is clinically meaningful,” said Kevin Kip, vice president of clinical analytics at UPMC.

While vaccines are usually injected straight into muscles, these shots are generally given at a 45-degree angle under the skin into fatty tissue on the underside of patients’ arms or their stomachs. The injections require smaller needles than vaccines and can be given one right after the other. Infusion takes 21 to 31 minutes. All patients are monitored for 30 minutes for drug reactions. McCreary said patients have had surprisingly few complaints about getting four shots and there were almost no adverse events.