Gilead, Moderna Candidates Ramp Up Coronavirus Drug, Vaccine Testing

Xconomy National — 

An investigational antiviral drug Gilead Sciences has been developing to treat infections caused by the Ebola virus will be tested in about 1,000 adults diagnosed with COVID-19, the novel coronavirus that has infected tens of thousands of people and killed more than 2,500.

On Wednesday, Foster City, CA-based Gilead (NASDAQ: GILD) announced the start of two Phase 3 clinical studies of the drug, a broad-spectrum antiviral called remdesivir, in countries with high numbers of diagnosed cases.

The trials, slated to kick off in March, will evaluate the safety and efficacy of two dosing durations of intravenously delivered remdesivir. One study will enroll about 400 patients with severe cases of coronavirus infection and randomize them to receive a five-day or a 10-day dose. In the other, about 600 patients with moderate manifestations of the viral infection will be randomized to receive one of the two dosing regimens or standard of care.

Gilead says the preclinical data on remdesivir in MERS and SARS, viral pathogens that are structurally similar to COVID-19, lead it to believe it could be effective against this latest pandemic. To date, only healthy volunteers, people infected with the Ebola virus, and a “small number” of coronavirus patients to whom Gilead has provided the experimental drug as an emergency treatment on a compassionate use basis have received it.

“Individual compassionate use cases are not sufficient to determine the safety and efficacy of remdesivir in treating COVID-19, which can only be determined through prospective clinical trials,” the company emphasized.

Other research into remdesivir as a potential treatment for coronavirus includes two clinical trials in China’s Hubei province, led by the China-Japan Friendship Hospital, which began enrolling patients earlier this month. Results are anticipated in April. And the National Institute of Allergy and Infectious Diseases (NIAID) on Tuesday said it has begun enrolling adults diagnosed with the disease in the first US clinical trial of the potential treatment at the University of Nebraska Medical Center in Omaha, NE. (The first person enrolled was previously quarantined on the Diamond Princess cruise ship, which earlier this month hosted the highest concentration of coronavirus cases outside of China, where the virus was first identified.)

Finding a safe and effective treatment isn’t the only challenge. So too is figuring out how to produce enough of it. Gilead says it is working through a stockpile of remdesivir—and the materials needed to create it—it had built in response to the Ebola outbreaks in West Africa in recent years. But supplies are limited, and the company says it is taking measures, including expanding its network of manufacturing partners. It has also started to produce it internally, to be better prepared in the case the drug does improve patients’ condition, and is OK’d as a treatment.

Also this week, Moderna (NASDAQ: MRNA) announced it had prepared an investigational vaccine aimed at preventing coronavirus infection. The vaccine is one of a slew of potential medicines the Cambridge, MA-based biotech is testing that use messenger RNA (mRNA) technology.

Moderna recently shipped the first batch of mRNA-1273 it made for human use to NIAID for use in a Phase 1 study. Making the batch was funded by the Coalition for Epidemic Preparedness Innovations (CEPI). Norway-based CEPI (pronounced “seppy”) is also providing funding to Pennsylvania-based Innovio (NASDAQ: INO) to advance a vaccine candidate.

The investigational vaccine against the novel coronavirus encodes for a form of the “spike” protein the virus uses to invade healthy cells. Once injected, the vaccine is designed to “train” the immune system to recognize those molecules. Were the vaccinated person to be infected, his or her immune system would know to respond to the pathogen.

The Moderna vaccine trial, which doesn’t have a firm start date, will take place at the Kaiser Permanente Washington Health Research Institute in Seattle, according to a NIAID spokesman. The institution is home to one of nine NIAID-supported Vaccine and Treatment Evaluation Unit sites nationwide.

Moderna is developing investigational drugs and vaccines designed to treat or prevent a slew of conditions, ranging from rare diseases to autoimmune conditions and cancers, by directing the body’s cells to make proteins to treat disease. Of the dozen programs it has advanced to the clinic, four are in or being readied for Phase 2 studies. And although the company hasn’t commercialized any treatments or vaccines, it noted it has had six positive Phase 1 clinical readouts from trials in which more than 1,000 patients were collectively enrolled across six different vaccines over the past four years.

Image: iStock/Daniel Chetroni