As part of a new clinical trial, Pfizer, the world’s largest pharmaceutical company, has begun giving people doses of a pill that fights COVID-19, National File reported.

Pfizer said it would submit for emergency permission between October and December this year if the study is successful.

“Success against #COVID19 will likely require both vaccines & treatments,” Pfizer CEO Albert Bourla said on Wednesday, Sept. 1. “We’re pleased to share we’ve started a Phase 2/3 study of our oral antiviral candidate-specifically designed to combat SARS-CoV-2-in non-hospitalized, low-risk adults.”

Pfizer also issued a press release the same week proclaiming “If successful, [the drug] has the potential to address a significant unmet medical need, providing patients with a novel oral therapy that could be prescribed at the first sign of infection, without requiring hospitalization.”

The company described the drug as an “investigational orally administered protease inhibitor antiviral therapy designed specifically to combat COVID-19—in non–hospitalized, symptomatic adult participants who have a confirmed diagnosis of SARS–CoV–2 infection and are not at increased risk of progressing to severe illness, which may lead to hospitalization or death.”

Adults with COVID-19 symptoms who have not been treated in hospital and are not at risk of becoming extremely ill are being examined in a mid-to-late-stage trial for the company’s oral antiviral treatment, per Sky News.

Pfizer is one of several pharmaceutical companies working on the first antiviral pill to treat early signs of the illness.

The treatment, PF-07321332, will be used with a low dose of ritonavir, which has previously been used with other antiviral medications, in research that included 1,140 people.

Patients will be given either the treatment or placebo orally every 12 hours for five days.

PF-07321332 is a treatment that works by blocking the key enzyme required for virus replication.

Pfizer is so confident that the pill will be quickly approved and mandated by governments that it has already launched a production line before clinical trials are completed.