As Gilead Sciences embarks on its own quest to widen the scope of its COVID-19 fighter Veklury—also known as remdesivir—a handful of researchers and biotechs are taking the fight into their own hands. Melbourne, Australia's Starpharma is the latest to join the fray, armed with a nanoparticle formulation of the antiviral that could help it move beyond the hospital.
Starpharma has developed a long-acting, water-soluble version of Veklury—still the only antiviral approved to tackle the novel coronavirus—using its drug delivery platform DEP.
Centered on dendrimers—a type of synthetic nanoparticle the company has used to develop (PDF) a suite of antibody-drug conjugates targeting solid tumors—Starpharma's "DEP remdesivir" boasts controlled release properties and is 100 times more soluble than standard Veklury, making it possible to deliver the med via subcutaneous injection, the company said in a release.
Gilead's version of Veklury is given as an infusion, a process that can take up to two hours each day for the duration of the five- or 10-day treatment courses COVID-19 patients are prescribed. By cutting out the need for trips to the infusion chair and prolonging Veklury's effects, Starphama thinks its formulation could reduce the number of treatments patients require and make them more convenient, too.
The subcutaneous dosing option could also help remdesivir move into the outpatient setting, where it could reach people at home or in care facilities, as well as those living in countries with less-developed healthcare systems, Starpharma CEO Jackie Fairley, B.V.Sc., said. That, in turn, could free up overburdened hospitals.
Meanwhile, Gilead has its own expansion efforts underway, racking up an expanded authorization for its Veklury formulation in the U.S. and advancing an inhaled version into the clinic to potentially tackle earlier-stage disease.
At the end of August, Veklury's emergency green light was upgraded to cover all hospitalized COVID-19 patients; previously, the antiviral only had an OK to treat patients hospitalized with severe disease. The expanded nod came on the heels of phase 3 data showing moderate patients on a five-day course of the drug, plus standard care, were 65% more likely to see improvement than patients on standard care alone.
That said, for patients on a 10-day course in that same study, the chances of improvement were not statistically significant, and JAMA experts, in an editorial accompanying the data release, argued that the readout was difficult to interpret. They went on to suggest the best patient population for the antiviral and the ideal length of time for Veklury treatment remain unclear.
Gilead has also advanced an inhaled version of Veklury into the clinic in hopes it could curb patients' early symptoms. “An inhaled formulation would be given through a nebulizer, which could potentially allow for easier administration outside the hospital, at earlier stages of disease,” Gilead CEO Daniel O’Day said in late June.
In July, two weeks after the FDA granted the big biotech the OK, Gilead kicked off a phase 1b trial to test its inhaled Veklury in 60 healthy U.S. volunteers. In addition to taking the treatment beyond the hospital, Gilead has advanced its nebulized Veklury in the hopes that it could curb certain side effects linked to the IV treatment, such as anemia, acute kidney injury and elevated liver enzymes, an indicator of liver damage.
Separate from Gilead's efforts, a team out of the University of Texas at Austin has also leveraged a drug delivery platform to develop an inhaled formulation of Veklury.
Led by department head Robert O. Williams III, Ph.D., researchers at the school's Division of Molecular Pharmaceutics and Drug Delivery pivoted their patented thin-film freezing tech—a platform used to improve the solubility of drugs—to create a dry powder version of the antiviral that could be administered through commercially available inhalers.
The department has licensed its thin-film freezing platform to neighboring Austin, Texas, biotech TFF Pharmaceuticals, which is also developing a dry powder formulation of the tapeworm med niclosamide, which has demonstrated some benefit in COVID-19 and other coronaviruses like SARS and MERS.