Sick elderly person wearing surgical face mask and being cared for by a clinician with stethoscope

A new COVID-19 treatment made by GlaxoSmithKline now is the third federally authorized monoclonal antibody therapy meant to help prevent severe disease outcomes in high-risk patients. But gene variants are interfering with the effectiveness of similar drugs previously approved for the same use.

The Food and Drug Administration on Wednesday issued an emergency use authorization for GSK’s investigational drug sotrovimab for use in patients aged 12 or more years who have mild-to-moderate COVID-19 and are at high risk for progression to hospitalization or death, the agency announced. This includes individuals aged 65 or more years who have certain medical conditions, it added.

In clinical tests, sotrovimab has been shown to neutralize gene virus variants first found in Britain, South Africa, Brazil, California, New York and India, according to the New York Times. The drug is delivered by infusion, as are the other therapies authorized by the FDA.

The federal government, meanwhile, has halted shipments of Eli Lilly’s authorized combination of monoclonal antibody drugs to six states where variants threaten to lessen their effectiveness. Those states include Arizona, California, Florida, Indiana, Oregon and Washington, where the frequency of variants identified in Brazil and South Africa have reached 10%, according to Endpoints News. 

The Department of Health and Human Services in March had halted nationwide distribution Eli Lilly’s single-drug monoclonal antibody infusion using bamlanivimab, also for lack of effectiveness against emerging virus variants, although its combination therapy remained in use at the time.

The FDA has encouraged healthcare providers in the six states to use Regeneron’s drug cocktail as an alternative monoclonal antibody therapy because it is more effective against the newer variants, Endpoints reported.

Monoclonal antibody therapies have been heralded by some geriatricians and industry advocates as a boon for long-term care — especially after Eli Lilly reported success in an unusual clinical trial conducted in nursing homes. Assisted living communities have been some of the most prolific users of the treatment, which has proven highly successful in keeping mild to moderate COVID-19 from progressing into a severe form, McKnight’s has reported.

The therapy has many strong points in its favor: clinical utility and approval for emergency use by the Food and Drug Administration. There also is no out-of-pocket cost-sharing for Eli Lilly’s and Regeneron’s authorized therapies, stores of which were purchased by the federal government. HHS allocates the drugs weekly based on each state’s share of confirmed COVID-19 cases, as well as the total number of hospitalized patients over a seven-day period. An initiative by HHS has been set up to funnel the infusion product directly to pharmacies serving long-term care facilities. 

There is no indication yet that federal agencies will move to purchase GSK’s drugs, however, according to the New York Times.