NEW YORK – The clinical trials of antibody drugs developed to fight against COVID-19 are taking longer than expected for pharmaceutical companies Regeneron and Eli Lilly, according to a report in the New York Times on August 14.

The slow start is due to “a dearth of tests, overwhelmed hospitals and reluctant patients,” the Times reported, adding that “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.”

Ambitious deadlines set by the companies have had to be pushed back as “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,” the Times reported, adding that “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, the Times reported, “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,” the Times reported.

While “the race to create a coronavirus vaccine” has garnered the most attention worldwide, “new drugs could also help curb the pandemic by making the disease less deadly,” the Times reported, noting that “because drugs are typically tested in sick patients in smaller clinical trials, they can also be developed more quickly than vaccines.”

“Eli Lilly and Regeneron are pursuing two of the most closely watched treatments: lab-engineered antibodies that could either fight off the virus in patients who are already sick or prevent infections in those who have been exposed,” the Times reported, adding that “although the Trump administration has heavily favored investment in vaccines, Regeneron has won deals from the federal government worth more than $500 million to ramp up manufacturing of its antibody treatment.”

“Both companies rushed to develop their products in record time and began large studies this summer at dozens of hospitals and clinics around the country,” the Times reported, noting that “they are testing various groups of patients, such as those who are positive but not yet sick enough to be hospitalized, and those who have been exposed to the virus from someone already infected,” and “all of the trials compare the experimental drugs to a placebo.”

The rapid spread of COVID-19 “has presented opportunities and challenges for the researchers testing antibodies,” the Times reported, adding that “as the number of infections mounted in states like Florida, Texas and Arizona, there was no shortage of patients who would be eligible for trials, but at the same time, the outbreaks overwhelmed the very hospitals that would be overseeing the studies.”

Dr. Skovronsky told the Times that during virtual meetings with doctors across the country, “some had to step out to care for patients who required emergency intervention,” and “That doesn’t happen when you’re setting up diabetes trials or cancer trials. We’ve had investigators say: ‘Look, I’d love to do research, but I don’t have time to set up a new trial. I’ve got an I.C.U. full of patients.’”

“One major hurdle has been testing,” the Times reported, adding that “in both of the outpatient trials run by Eli Lilly and Regeneron, doctors must compete with a ticking clock,” and “according to the rules of the Regeneron trial, a patient must be treated with the antibodies within seven days of the onset of symptoms,” while “both the Regeneron and Eli Lilly trials require giving the drug within three days of taking a positive test, but with turnaround times in some areas lagging for five days or more, keeping within those time frames has proved difficult.”

Dr. Anita Kohli, the director of research at Arizona Clinical Trials, a Regeneron trial site in Mesa, AZ, said she “got a rush of people wanting to volunteer for the outpatient study earlier this summer, when the outbreak was peaking in her state,” the Times reported.

“Our phones were ringing, probably off the hook the first two weeks,” she told the Times, adding that “as labs were inundated with samples, straining supply chains and delaying results, … enrolling patients became difficult.”

“If people are getting tested at these facilities, but they don’t have the results, then how do we enroll them in trials?” Dr. Kohli told the Times, noting that “Regeneron sent her a rapid-testing machine to speed up the results, and Eli Lilly did the same for its trial, which she is also running.”

A spokeswoman for Regeneron said that “the company had sent out ‘a few dozen’ testing machines to clinical trial sites, and was planning to send more in the coming days,” the Times reported, adding that “Eli Lilly said it was working with state health departments and other local authorities to help speed up testing in certain areas, in addition to supplying some sites with testing machines.”

The Eli Lilly outpatient trial aims to include 400 patients, while “the similar Regeneron study has a goal of enrolling about 1,500 patients,” the Times reported.

Concerning the reluctance of some patients to join the clinical trials, the Times reported that “many people associate clinical trials with treatments that are given in life-or-death situations, and don’t want to risk taking an experimental drug for an illness they may overcome on their own,” while “others have the opposite rationale: They don’t want to go through the hassle of a trial only to receive a placebo.”

Doctors running studies are also not allowed to make a “hard sell” to get patients to join in, the Times reported.

Dr. G. Marshall Lyon III, who is leading the Regeneron clinical trials at Emory University in Atlanta, told the Times, “We can’t sort of paint it as a positive or a negative. We don’t know if it’s going to be directly beneficial to you; we don’t know if it’s going to be harmful to you,” adding that “enrollment in the trial was going more slowly than he expected,” and that “most people ended up ‘taking a wait-and-see attitude.’”