June 25 (Reuters) - U.S. health officials on Friday paused the distribution of Eli Lilly's COVID-19 antibody cocktail therapy as it failed to show effectiveness against the coronavirus variants that were first identified in Brazil and South Africa.

The decision by the U.S. Department of Health and Human Services (HHS) is based on laboratory analyses that showed Lilly's dual-antibody therapy - bamlanivimab and etesevimab - was not active against either variant.

The department also halted the distribution of standalone etesevimab to be paired with existing supply of bamlanivimab.

"As variants continue to evolve and their patterns of transmission and prevalence shift, we will continue our work with governments and regulators worldwide to ensure our antibodies are available to appropriate patients," Lilly said in an email to Reuters.

The Centers for Disease Control and Prevention (CDC) said the Gamma variant, first seen in Brazil, and the Beta variant, first found in South Africa, together made up for more 11% of infections in the United States and that the number is growing.

The U.S. health regulator in April revoked the emergency use authorization for Lilly's bamlanivimab and required it to be used along with etesevimab to achieve greater effectiveness against emerging variants.

Lilly in April expected the combination to bring in sales of $1 billion to $1.5 billion this year, trimming its previous forecast of as much as $2 billion, as the rollout of vaccines dealt a blow to demand for the therapy.

The HHS also said Regeneron's antibody therapy, REGEN-COV, and GlaxoSmithKline Plc and partner Vir Biotechnology's sotrovimab are likely to be effective against the variants.

The FDA recommended hospitals to use Regeneron and GSK/Vir therapies instead of Eli Lilly's combo therapy until further notice. (Reporting by Manojna Maddipatla and Mrinalika Roy in Bengaluru; Editing by Arun Koyyur and Ramakrishnan M.)