April 1 (Reuters) - Eli Lilly LLY.N said on Tuesday it had sued two mass compounders for selling unapproved products that contain tirzepatide, the main ingredient in its popular weight-loss and diabetes medicines.

This comes after a U.S. federal judge last month refused to allow compounding pharmacies to keep making copies of these drugs in the United States.

Compounders had been allowed to produce hundreds of thousands of doses of copies of obesity drugs only while the FDA said there was a shortage of them.

Lilly has already sued more than two dozen medical spas, wellness centers and compounding pharmacies for selling products claiming to contain tirzepatide.

The new lawsuits from Lilly name Strive Pharmacy LLC and Empower Clinic Services LLC. Lilly said the companies were selling unapproved drugs and making false claims about efficacy and safety.

Lilly said Strive's tirzepatide products, which come in standard doses added with vitamin B12 or glycine, are falsely suggested to be safer and more effective than FDA-approved medicines.

Empower offers compounded tirzepatide as an oral pill and an injectable version with a form of vitamin B3 added to it, falsely suggesting their efficacy by citing Lilly's own clinical studies, according to Lilly.

The complaint against Empower was filed in the district court of New Jersey and the one against Strive was filed in the district court of Delaware.

The drugmaker will also send about fifty cease and desist letters to compounders and telehealth companies, asking them to confirm that they have already ceased mass compounding.

(Reporting by Christy Santhosh in Bengaluru; Editing by Saumyadeb Chakrabarty)

((Christy.Santhosh@thomsonreuters.com;))