SAN DIEGOUSPlabs LLC, the manufacturer of such sports supplements as Jack3d and OxyElite Pro, is facing a growing number of lawsuits over its products thanks to an outbreak of hepatitis and liver failure.

In the latest development, a proposed class action lawsuit was filed Thursday in California federal court against USPlabs and GNC Corp., which sells USPlabs supplements.

"Defendants' claims of safe and effective weight loss and energy health benefits are false, misleading, reasonably likely to deceive the public, and constitute an unfair business practice," alleged the complaint, which was filed by the Desai Law Firm P.C. in Costa Mesa.

The suit proposed to represent a nationwide class of "All persons who purchased OxyElite Pro and Jack3D in the United States for personal use." It alleged violations of the Consumer Legal Remedies Act and California Business & Professions Code as well as breach of express warranty, breach of implied warranty and unjust enrichment.

Dallas-based USPlabs did not immediately respond Friday to a request for comment. Pittsburgh-based GNC declined comment, citing its policy.

Both companies previously were named as defendants in two lawsuits that were filed on behalf of victims of a non-viral hepatitis outbreak in Hawaii. The outbreak has been associated with one death, two liver transplants and dozens of other illnesses.

USPlabs has consistently proclaimed its supplements are safe. It also believes counterfeit products of OxyElite Pro have been sold. Asked whether FDA has found evidence of any counterfeit products, a spokesperson for the agency, Marianna Naum, declined comment Thursday, citing an ongoing investigation. 

Naum said the agency is reviewing 37 medical records that involve consumers who reported ingesting OxyElite Pro before they fell ill. She said 27 patients are from Hawaii, while the remainder live in the continental United States.

Patients reported taking the recommended dosage of OxyElite Pro and local health officials were unaware of any conditions that would predispose the individuals to liver failure, Sarah Park, M.D., State Epidemiologist with the Hawaii State Department of Health, told Natural Products INSIDER in an October 2013 interview. 

The hepatitis outbreak is the latest crisis to rock USPlabs, whose supplements containing a stimulant known as DMAA have been linked to deaths and other illnesses and were later seized by the government in an enforcement action. The products, valued at roughly USD $8.5 million, were subsequently voluntarily destroyed.

USPlabs reformulated OxyElite Pro and Jack3d to exclude DMAA. And last month, the company advised FDA it would remove the ingredient aegeline from its products after the agency claimed the substance was not proven to be safe.