May 30 (Reuters) - Novo Nordisk said on Thursday it had sued nine more medical spas, wellness clinics and pharmacies in the U.S. for selling products claiming to contain semaglutide, the key ingredient in its popular weight-loss drug Wegovy.

The Danish drugmaker first filed lawsuits over the sale of copycat versions of semaglutide last June, later amending one after samples it tested were found to be as much as 33% impure.

The nine new suits name Aesthetic Maison, BOF Medical Center, DoctorsRx, G2 Telemedicine, GenericOzempic.com, MD Exam, MediOAK Pharmacy, Midtown Express, and Weight Loss MD as defendants.

They were filed in federal courts in Colorado, Florida, Illinois, Montana, Texas and Tennessee.

“Non-FDA approved compounded drugs claiming to contain semaglutide with high levels of known impurities and unknown impurities pose significant risks to patients and may lead to serious and life-threatening reactions,” said Doug Langa, Novo's head of North America operations.

Novo said in its lawsuit against Aesthetic Maison that the company was selling products claiming to contain semaglutide directly to patients without any prescription from a medical professional.

Testing showed Midtown Express's drug contained no semaglutide and MediOAK's product was of a far lower strength than advertised, Novo claimed in its lawsuits against those entities.

Novo also filed new allegations against Florida-based pharmacies TruLife and WellHealth, which it first sued in July.

The drugmaker said that when it tested the products being sold by WellHealth, it found impurities of up to 24%, including formaldehyde adduct, dimers, and other unknown impurities. Novo said it found impurities in TruLife's products as well.

The company said it has now filed 21 lawsuits in total against entities selling products claiming to contain semaglutide, five of which have led to them being barred from selling their disputed products.

Novo's biggest rival in the obesity drug market, Eli Lilly, has also sued several medical spas, weight-loss clinics and compounding pharmacies over the past year to stop them from selling products purporting to contain tirzepatide, the active ingredient in its weight-loss drug Zepbound.

At least four of those lawsuits from Lilly have either been settled, withdrawn or dismissed. (Reporting by Patrick Wingrove; Editing by Chizu Nomiyama)