Trials of coronavirus antibody drugs taking longer than expected

NEW YORK • As the coronavirus pandemic continues to wreak havoc in the US 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 have said 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.

Regeneron, which earlier 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 end-September.

Eli Lilly's chief scientific officer, who said in June that its antibody treatment might be ready next month, last week said he now hopes for something before the end of the year. "I wish we could go faster, there's no question about that," said Dr Daniel Skovronsky. "I guess in my hopes and dreams, we enrol the patients in a week or two, but it's taking longer than that."

A spokesman for Regeneron, Ms Hala Mirza, said all clinical trials involved an early learning period and that it 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 on 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 coronavirus in sick patients or prevent infections in those who have been exposed.

Although the Trump administration favours investment in vaccines, Regeneron has won deals from the federal government worth more than US$500 million (S$685 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.

As the number of infections mounted in states such as 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.

One major hurdle has been testing. In both of the outpatient trials run by Eli Lilly and Regeneron, doctors must compete with a ticking clock. According to the rules of the Regeneron trial, a patient must be treated with the antibodies within seven days of the onset of symptoms. Both the Regeneron and Eli Lilly trials require giving a patient 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, director of research at Arizona Clinical Trials, a Regeneron trial site, said there was a rush of people wanting to volunteer for the outpatient study earlier this summer, when the outbreak was peaking in her state. But as labs were flooded with samples, straining supply chains and delaying results, Dr Kohli said enrolling patients became difficult. "If people are getting tested at these facilities, but they don't have the results, then how do we enrol them in trials?" she pointed out.

NYTIMES