Gilead slides as second Chinese trial of remdesivir is stopped

Two investigator-led phase 3 trials of Gilead Sciences’ coronavirus candidate remdesivir have now been halted because they weren’t able to enrol enough subjects.

Updates posted on the clinicaltrials.gov database today say that the two trials – one in mild-to-moderate patients and another in those with severe COVID-19 – were stopped because “the epidemic of COVID-19 has been controlled well in China [and] no eligible patients can be enrolled at present.”

The trial in mild and moderate patients (NCT04252664) has been suspended, while the study in severely-ill subjects (NCT04257656) has been terminated, according to the updates.

Shares in Gilead slid after the news emerged, amid disappointment that there will be a further delay before clinical readouts will become available to show whether remdesivir will have a role to play in treating the coronavirus pandemic. Both Chinese studies were due to generate results this month.

In a research note published after news of the suspension of the mild-to-moderate trial emerged, analysts at RBC Capital said the lack of information from the investigators was worrying.

All told, 237 out of a target study population of 300 were enrolled before it was placed on hold, they said, and with no data being revealed “any benefits were likely inconclusive,” they suggested.

Gilead-sponsored trials in severely-ill patients are due in late April, followed by a readout in mild and moderate patients in May. However the severe study doesn’t have a control arm which could make the results difficult to interpret, says RBC.

Meanwhile, there’s also some speculation that remdesivir is more likely to work in patients with less severe COVID-19.

GlobalData suggested recently that remdesivir’s antiviral mechanism means it “has the potential to decrease viral load in less-severe patients” with COVID-19, but that in those who are more critically ill “the disease’s inflammatory impact becomes the more significant factor to address.”

The extended timeline for results is undeniably a blow, as remdesivir remains the front runner among antiviral drugs for COVID-19, with the pandemic steadily gathering pace outside China. At last count, the number of confirmed cases worldwide had risen above the 2 million mark, with deaths approaching 130,000.

So far the only data on the drug in this setting comes from an open-label study of the drug in a varied group of compassionate-use patients, which pointed to a benefit but was difficult to interpret.

With the two Chinese studies looking defunct, the number of remdesivir trials has been cut from seven to five.

Aside from the two company-sponsored studies, there are also trials ongoing at National Institute of Allergy and Infectious Disease (NIAID) in the US and France’s INSERM research institute, while the World Health Organization (WHO) is including remdesivir in its multidrug SOLIDARITY trial.