Benzinga | Jan 13, 2022 11:48AM EST

GSK And Vir Submit Emergency Use Authorization Application To FDA For Intramuscular Administration Of Sotrovimab For The Early Treatment Of COVID-19

GlaxoSmithKline plc (NYSE:GSK) and Vir Biotechnology, Inc. (NASDAQ:VIR) today announced the submission of an application to the US Food and Drug Administration (FDA) requesting an amendment to the Emergency Use Authorization (EUA) for sotrovimab, an investigational monoclonal antibody for the early treatment of COVID-19, to include intramuscular (IM) administration. The EUA for sotrovimab was granted by the FDA in May 2021 as an investigational single-dose intravenous (IV) (500 mg) infusion SARS-CoV-2 monoclonal antibody for the early treatment of COVID-19, and the companies are requesting an expansion to the EUA to also include IM administration (500 mg).

Under the current EUA, sotrovimab can be used for the treatment of mild-to-moderate COVID-19 in adults and pediatric patients (12 years of age and older weighing at least 40 kg) with positive results of direct SARS-CoV-2 viral testing, and who are at high risk for progression to severe COVID-19, including hospitalization or death.

This submission is based on the Phase 3, randomized, open-label, non-inferiority COMET-TAIL trial, which achieved its primary endpoint, demonstrating that 500mg IM administration of sotrovimab (n=376) was non-inferior and offered similar efficacy to 500 mg IV administration (n=378) for the early treatment of mild-to-moderate COVID-19 in high-risk, non-hospitalized adults and adolescents. Low rates of serious adverse events (?1% in both arms) were observed in the headline data.

About Sotrovimab

Sotrovimab is an investigational SARS-CoV-2-neutralizing monoclonal antibody. The antibody binds to an epitope on SARS-CoV-2 shared with SARS-CoV-1 (the virus that causes SARS), indicating that the epitope is highly conserved, which may make it more difficult for resistance to develop. Sotrovimab, which incorporates Xencor, Inc.'s Xtend(tm) technology, has also been designed to achieve high concentration in the lungs to ensure optimal penetration into airway tissues affected by SARS-CoV-2 and to have an extended half-life.

About the Sotrovimab Clinical Development Program

* COMET-ICE: a Phase 3, multi-center, double-blind, placebo-controlled trial investigated IV infusion of sotrovimab in adults with mild-to-moderate COVID-19 at high risk of progression to severe disease, who are not hospitalized and not requiring oxygen. The final COMET-ICE trial results in the full trial population of 1,057 participants demonstrated a 79% reduction (adjusted relative risk reduction) (p<0.001) in hospitalization for more than 24 hours or death due to any cause by Day 29 compared to placebo, meeting the primary endpoint of the trial. Interim data were published in The New England Journal of Medicine on October 27, 2021 and final data were pre-published on November 8, 2021 on medRxiv.

* COMET-TAIL: an ongoing Phase 3, randomized, multi-center, open-label, non-inferiority trial of IM versus IV administration of sotrovimab for the early treatment of mild-to-moderate COVID-19 in high-risk non-hospitalized adult and pediatric patients (12 years of age and older). The trial's primary endpoint was met, and headline data demonstrated that 500mg IM-administered sotrovimab was non-inferior and offered similar efficacy to IV administration for high-risk populations. In the IM administration (500mg) arm of the trial, there was a 2.7% rate of progression to hospitalization for more than 24 hours or death through Day 29 of the trial, compared to 1.3% in the IV administration arm (also 500mg). The adjusted difference between the IM and IV arms of the trial was 1.07% with a 95% confidence interval (CI) of -1.25% to 3.39%. The upper bound of the 95% CI is within the predetermined 3.5% non-inferiority margin set for the trial's primary endpoint. Low rates of serious adverse events (?1% in both arms) were observed in the headline data. The trial originally included three arms: 500mg of sotrovimab given intravenously, and two intramuscular arms, consisting of 500mg and a low dose of 250mg. An independent safety monitoring committee recommended enrollment in the 250mg arm be discontinued after a greater number of hospitalizations in that arm was noted. The 500mg dose arms were recommended to continue with enrollment as planned. The companies plan to submit the complete COMET-TAIL data set to a peer-reviewed journal for publication in the first quarter of 2022.

* COMET-PEAK: a Phase 2, randomized, multi-center, parallel group trial evaluating IV and IM administration of sotrovimab in outpatients with mild-to-moderate COVID-19. The companies plan to submit the full COMET-PEAK data set to a peer-reviewed journal for publication.

* Additionally, GSK and Vir are partnering to investigate the use of sotrovimab in uninfected immunocompromised adults to determine whether sotrovimab can prevent symptomatic COVID-19 infection. GSK and Vir are supporting investigator sponsored studies and fostering scientific collaborations with both experienced investigators and networks, who are involved in the continuum of care of immunocompromised patients, to understand the role sotrovimab for prophylaxis could play in this population. Discussions with regulatory authorities regarding the prophylaxis program will occur in due course.

* Sotrovimab is also being studied by the University of Oxford among patients hospitalized with COVID-19 in the United Kingdom as part of the Randomized Evaluation of COVID-19 Therapy (RECOVERY) Trial.

Sotrovimab in the United States

The following is a summary of information for sotrovimab. Healthcare providers in the US should review the Fact Sheets for information about the authorized use of sotrovimab and mandatory requirements of the EUA. Please see the Food and Drug Administration (FDA) Letter of Authorization, full Fact Sheet for Healthcare Providers and full Fact Sheet for Patients, Parents, and Caregivers.

Sotrovimab has been authorized by the FDA for the emergency use described below. Sotrovimab is not FDA-approved for this use.

Sotrovimab is authorized only for the duration of the declaration that circumstances exist justifying the authorization of the emergency use of sotrovimab under section 564(b)(1) of the Act, 21 U.S.C. ? 360bbb-3(b)(1), unless the authorization is terminated or revoked sooner.

Authorized Use

The FDA has issued an EUA to permit the emergency use of the unapproved product sotrovimab for the treatment of mild-to-moderate coronavirus disease 2019 (COVID-19) in adults and pediatric patients (12 years of age and older weighing at least 40kg) with positive results of direct SARS-CoV-2 viral testing, and who are at high risk for progression to severe COVID-19, including hospitalization or death.

Limitations of Authorized Use

Sotrovimab is not authorized for use in patients:

* who are hospitalized due to COVID-19, OR

* who require oxygen therapy due to COVID-19, OR

* who require an increase in baseline oxygen flow rate due to COVID-19 (in those on chronic oxygen therapy due to underlying non-COVID-19 related comorbidity)

Benefit of treatment with sotrovimab has not been observed in patients hospitalized due to COVID19. SARS-CoV-2 monoclonal antibodies may be associated with worse clinical outcomes when administered to hospitalized patients with COVID-19 requiring high flow oxygen or mechanical ventilation.