Gilead Sciences wasted no time beginning testing of an inhaled formulation of its COVID-19 drug remdesivir.
Two weeks after securing an FDA go-ahead, the biotech on Wednesday said it had kicked off a phase 1b trial to evaluate the safety of inhaled remdesivir in 60 healthy volunteers in the U.S.
The hope is that the inhaled formulation—as compared with the drug’s currently available intravenous form—could reach the outpatient setting, where patients have less severe disease, and that early treatment could help them avoid hospitalization.
In the large-scale ACTT-1 study conducted by the National Institutes of Health, intravenous remdesivir already showed it could cut recovery time by four days, or about 31%, among hospitalized patients. But its benefits appear less significant for patients with mild or moderate disease.
Gilead argues that delivering the antiviral directly to the lungs, where the viral infection is worst, might lead to better outcomes for early-stage COVID-19 patients who don’t need to be hospitalized.
“Based on current scientific understanding, the upper respiratory tract is the most prevalent site of SARS-CoV-2 infection early in disease,” Gilead’s chief medical officer, Merdad Parsey, said in a statement.
Then there’s the safety concern. In the ACTT-1 trial, some patients who got intravenous remdesivir experienced side effects such as anemia, acute kidney injury and elevated liver enzymes—an indicator of liver damage—though none of them seemed to be much more frequent than the rates seen in the placebo group. Nevertheless, Gilead hopes inhaled remdesivir could reduce the side-effect burden.
“Delivering remdesivir directly to the primary site of infection with a nebulized, inhaled solution may enable more targeted and accessible administration in non-hospitalized patients and potentially lower systemic exposure to the drug,” Parsey explained.
What more, while intravenous infusion by a healthcare practitioner may work in the inpatient setting, outpatient care requires a more convenient administration method.
However, as GlobalData analyst Angad Lotay noted in a recent analysis, the inhaled formulation has its own hurdles, including cost and practicality.
“Although there are chronic conditions that permit training to reconstitute medication for self-administration by injection or nebulizer, it is uncommon to see this in acute infections without the assistance of trained staff,” Lotay said. “Supplying equipment to each patient would certainly raise concerns regarding costs and supply, which would bare a significant barrier.”
Gilead didn’t immediately respond to a FiercePharma request for clarification on whether the inhaled version can be self-administered by patients at home or still requires doctor’s supervision.
Besides the inhaled formulation, Gilead has also said it will test the IV version in outpatient settings such as infusion centers and nursing homes. A clinical trial for children is being planned. Combination studies with anti-inflammatory agents—including Roche’s Actemra and Eli Lilly’s Olumiant—are also underway.