Clinical Trials of Coronavirus Drugs Are Taking Longer Than Expected

As the coronavirus pandemic continues to wreak havoc in the United States and treatments are needed more than ever, clinical trials for some of the most promising experimental drugs are taking longer than expected.

Researchers at a dozen clinical trial sites said that testing delays, staffing shortages, space constraints and reluctant patients were complicating their efforts to test monoclonal antibodies, man-made drugs that mimic the molecular soldiers made by the human immune system.

As a result, once-ambitious deadlines are slipping. The drug maker Regeneron, which previously said it could have emergency doses of its antibody cocktail ready by the end of summer, has shifted to talking about how “initial data” could be available by the end of September.

And Eli Lilly’s chief scientific officer said in June that its antibody treatment might be ready in September, but in an interview this week, he said he now hopes for something before the end of the year.

“Of course, I wish we could go faster — there’s no question about that,” said the Eli Lilly executive, Dr. Daniel Skovronsky. “I guess in my hopes and dreams, we enroll the patients in a week or two, but it’s taking longer than that.”

A spokeswoman for Regeneron, Hala Mirza, said that all clinical trials involved an early learning period, and that the company was “seeing positive momentum in recent days” as it has sent testing machines to some research sites and has broadened criteria to allow more patients to participate.

While much of the world’s focus has been on the race to create a coronavirus vaccine, new drugs could also help curb the pandemic by making the disease less deadly. Because drugs are typically tested in sick patients in smaller clinical trials, they can also be developed more quickly than vaccines. ...