The cancer center has continued running critical trials that are well underway, including through virtual checkups. “This morning I walked into the clinic with my stethoscope and iPad,” Herbst says.

Fears abound over exposing patients to the virus, especially because many cancer drugs weaken the immune system to the point where it can’t mount a counterattack. Drugmakers, doctors, and ethics committees must weigh the risk of a clinical trial patient contracting Covid-19 against the benefits of a therapy. It’s not always clear-cut. “We’ve had to think about, how essential are these study visits?” asks Susanna Naggie of Duke University School of Medicine, who provides oversight of trials there. “Is the participant already receiving a medication that they cannot otherwise get? Is this a potential lifesaving medication?”

Sometimes, patients voluntarily drop out of studies that are midway through or in late stages to cut down on exposure to the new coronavirus, raising the specter of costly clinical trial reboots. (I recently covered this in an article about Covid-19 scrambling the biotech industry.)

Emma Meagher, chief clinical research officer for Perelman School of Medicine at the University of Pennsylvania, says there’s no telling when clinical trials will go back to normal. It depends on the severity of the outbreak–and how hard-hit a particular region is. And in the future, things won’t necessarily be the same. “I think we will become more careful and more thoughtful about what actually requires in-person visits versus remote visits,” she says.

For Sharon Terry, her 25-year quest to find a cure for her two kids’ rare disease just entered an unwelcome phase: navigating clinical trial headaches. In 1994, Terry suspected a reoccurring rash on her daughter indicated something more serious. Confirming Terry’s instincts, a dermatologist diagnosed both her daughter and her son with pseudoxanthoma elasticum, or PXE. The slow-onset disorder can obscure vision and cause a host of cardiovascular issues.

When scientists had few answers, Terry and her ex-husband formed PXE International, a nonprofit that orchestrates research into the disease. By 2000 the organization’s scientific partnerships successfully pinpointed the gene behind the mutation that causes PXE, but it took years to understand the disruption that ensues. It turns out, those with PXE have lower levels of an enzyme called pyrophosphate, causing calcification of elastic tissues.

Terry has long dreamed of the next step: early-stage clinical trials to assess a pair of potential PXE treatments. One study led by PXE International will analyze whether simply ingesting pyrophosphate–already approved as a food additive by the US Food and Drug Administration–helps PXE patients. The group also plans to support a biomarker study, followed by an early-stage clinical trial to assess whether an existing drug from Japanese pharmaceutical Daiichi Sankyo can fight PXE. But the pandemic has pushed back the studies, possibly by six to nine months. “When it was 1999 and 2000, we knew we were many years from a treatment,” Terry says. “And now, everybody was pretty hyped up, geared up and excited that we might be on the verge.”

But tacking a delay onto what’s already been a lengthy search comes at a cost. “Pushing it back means some people are going to have vision loss when we could have potentially had a treatment sooner,” says Ian Terry, Sharon’s son, now 30 years old. Ian describes himself as healthy but says he keeps his fingers crossed: The disease progresses with age.

With a surge in clinical trial disruptions, doctors who are still running studies are turning to desktops and tablets, virtual screenings, and uploading paperwork remotely. When possible, medications are being mailed, and health care workers travel to deliver home care. The FDA recently encouraged the pivot, noting that some trials could go virtual. Suddenly there’s willingness to “adopt technology that exists to run clinical trials in the 21st century,” says Greg Dombal, the chief operating officer of Halloran Consulting, which advises companies on clinical trials.