Rene Roach fired off a quick email in late March for an update on a colorectal cancer clinical trial for which she hoped to qualify.

Worried about the coronavirus, she asked, almost as an afterthought, whether the study had been put on hold because of the pandemic.The answer crushed her: It had been.

"That's when COVID-19 shut down everything," says Roach, 50, of Germantown, Md.

Roach assumed that there would be workarounds for patients like her, who have stage IV cancer. These patients often depend on clinical trials as their best chance to knock cancer out when other therapies have failed.

For now, she's being treated with traditional chemotherapy, but she was counting on the drug cocktail from the clinical trial. She figures if chemo was going to rid her body of cancer for good, it would have done so already.

"It's buying time. But how much time is that? I don't know," she says. "And so if this stops working, what else do I have?"

The COVID-19 pandemic has forced hundreds of clinical trials to grind to a halt, stalling research into cancer, strokes, dementia and more, an NPR analysis of federal clinical trials data has found.

As Americans have been told to stay home to prevent spreading the novel coronavirus, people enrolled in clinical trials are being notified that those trials have been suspended or won't begin as originally planned.

NPR has identified 440 studies that have been suspended since March 1 because of the outbreak. About a quarter of the studies put on hold were for cancer treatment. The studies involved as many as 200,000 people, though it's hard to know precisely how many were active in the studies at the time they were halted.

"It's a whole cascade of effects occurring here that is really interrupting the ability of patients to obtain treatment in clinical trials," says Dr. Richard Schilsky, chief medical officer of the American Society of Clinical Oncology. "We're hearing at least anecdotally that enrollment is falling."

Drugmakers, university medical centers, hospitals and community research centers have all suspended various research projects because of the outbreak, says Dr. Lindsay McNair, chief medical officer for WIRB-Copernicus Group, a company that offers ethical and regulatory review of clinical trials.

Many institutions try to keep studies going if they have a "direct benefit" for patients, but where to draw that line can be unclear, she says. As a result, organizations are weighing whether to shut down on a case-by-case basis.

A key consideration is whether study participants' extra visits to health care facilities are worth the risk of catching the coronavirus. Another factor is whether health care staff are available to continue running trials despite the added burden COVID-19 is putting on hospitals and clinics.

It's incredibly difficult for patients, McNair says. "A lot of these people have waited a long time to get into a clinical trial."

Schilsky says he's heard about studies that require biopsies being stymied because hospital radiology suites have closed, for example.

"It creates a real conundrum," he says, particularly if the biopsy was needed to determine whether the treatment worked for patients. "Data from many studies that were eagerly anticipated is going to take a lot longer to develop. It's going to just slow down the whole cancer research enterprise."

Freezing these trials will have long-term effects, too, says Ken Kaitin, who directs the Tufts Center for the Study of Drug Development.

"If you're hoping and praying for a brand-new drug, likely you will have to wait longer than expected," Kaitin says.

Cancer patient Roach doesn't know when the trial she's hoping to take part in will reopen. It could be months or longer. There's a chance that when it does her cancer could have progressed to the point where she's no longer eligible to participate.

"I know right now we're ... living in this world of uncertainty. And many people are dying from this disease and from the virus," she says. "You know, we're out here dying from cancer. And just to have things stopped. I don't know. It's not really fair."

Clinical trials can be crucial for patients with cancer and other serious conditions. Sometimes, it's the only care they can access. Other times, it's their best shot at keeping a disease at bay.

"For many patients, being enrolled in a clinical trial is the difference between staying alive to get to their next birthday or their child's next birthday," says Rena Conti, a health economist at Boston University. "And this new reality that we're living in has some really serious implications for people's health, but also their ability to take care of their families and ultimately their ability to work."

Conti is the principal investigator in a study on the financial burden of cancer. It's survey-based, which means patients don't need to go to health care facilities for blood draws and other tests. But because recruitment involved seeing patients in the clinic, enrolling new patients has come to a stop.

And it's not just cancer trials that are feeling the effects of COVID-19.

Craig Leppert, who lives in Los Angeles, was looking forward to a clinical trial that would allow him to spend long stretches of time outside in the sun for the first time in his life. He has erythropoietic protoporphyria, a rare enzyme abnormality that causes a chemical to build up in the blood and skin and makes people who have it sensitive to sunlight.

The pain is like "a combination of having a broken bone, cutting yourself by accident and burning yourself on a hot stove," says Leppert, 29. "If there's some terrible bartender who would mix those three things together, it kind of feels a little bit like that. There's nothing to subdue the pain."

He's participated in the first two clinical trials for a drug that would prevent this reaction, but he was in the placebo group, meaning he didn't get the drug.

In the upcoming phase III clinical trial, everyone gets the drug after six months. He admits he'd started to hope that he would be able to do things this summer that he'd normally have to avoid, like going to the beach.

But Leppert is resigned to waiting. "Hey, this is the rules of the game," he says. "Another summer we're just going to ride it out."

While he's disappointed, he knows it's even more crushing for children with this disease, who need to face another summer indoors while their friends play outside. They'll also have more nights ahead unable to sleep through pain because of a few minutes in the sun, he says.

"People could be waiting a lifetime for a therapy that will be stalled or delayed," says Pamela Gavin, chief strategy officer at the National Organization for Rare Disorders. "But the community is full of hope."

The rare disease community is used to rolling with the punches, she says. "It's a really resilient group of people."

Some studies are able to adapt, however. The Food and Drug Administration published guidelines allowing for more flexibility during the COVID-19 pandemic.

Cedron WIlliams, who directs the office of clinical trials for East Carolina University in Greenville, N.C, says the agency's move has allowed him to have conversations with study sponsors to keep trials going for patients who depend on them.

In some studies, even a slightly delayed checkup is a deviation from protocol, so he has his work cut out for him.

"I do think that it's really really important that the federal guidance has allowed room for immediate changes," he says. "Had it not been for the COVID-19 response, I don't think we would have had the room to be as flexible."

Some studies are being adjusted to send patients pharmaceuticals in the mail or rely on telemedicine instead of in-person consultations, McNair says.

Others have continued with more minor changes.

Beth Anastasia, who has stage IV non-small cell lung cancer and lives in Mount Laurel, N.J., went to her first clinical trial infusion without her husband last week. The facility instituted a new policy to prevent the spread of COVID-19: no more companions.

"I have a wonderful husband who goes to every stinkin' infusion with me, sits in the crappy guest chairs ... and then spends six hours every other Thursday with me," she says. "He can't do that anymore."

They don't normally talk much during the infusions, but the company had been a source of comfort. "It was just the support of someone being there — for both of us — that's important," she says. "And it was odd not having him there."

But Anastasia knows the policy is in place for a good reason.

"I have an extraordinary care team," she says. "And I want to keep them safe because they keep me safe."

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