District Judge Amy Berman Jackson in Washington, D.C. made the decision a month after the company filed for bankruptcy protection, blaming inaction by the Food and Drug Administration.

K-V had filed the lawsuit in July in an unsuccessful last-gasp attempt to stay afloat, saying it would not have enough revenue from Makena sales to pay its creditors if the FDA did not take action against the unapproved versions.

The injectable hormonal drug reduces the risk of pre-term birth in women who have delivered early in the past.

Pharmacies had already been compounding such a drug for years at far lower prices than Makena, using an active ingredient, hydroxyprogesterone, available on the market without formal FDA approval.

K-V gained approval to sell Makena last year.

"The central issue for K-V Pharmaceutical ... has always been to ensure that pregnant women have access to Makena, the only drug approved by the FDA for their condition," company spokesman Tony Herrling said.

K-V had claimed in its lawsuit that the FDA had decided not to crack down on the pharmacies out of concern for insurance companies' costs, rather than patients' needs.

But Jackson said in her ruling that the FDA's move was within its discretion and by law is not subject to judicial review.

"This case is fundamentally an effort to get the court to direct and oversee the FDA's enforcement activities, and that it cannot do," she wrote.

FDA representatives could not immediately be reached for comment Thursday evening.

The case is K-V Pharmaceutical Company v. FDA, U.S. District Court, District of Columbia, No. 12-01105.

(Reporting by Joseph Ax; Editing by Richard Chang)

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