Last week, the US Food and Drug Administration (FDA) granted additional exclusivity to Eagle Pharmaceuticals’ cancer medicine Treanda (bendamustine hydrochloride), a decision that effectively halts the introduction of generic versions of the injection until 2022, which one analyst said could cost the public $3 billion.

The decision by FDA comes as the company’s other bendamustine hydrochloride product, known as Bendeka, won seven years of orphan drug exclusivity last summer because of a US district court win for the company against FDA.

FDA said in its conclusion last week that because of the court's decision, "the scope of Bendeka's exclusivity extends to all applications containing the same active moiety as Bendeka, bendamustine, and bars the approval of any application containing bendamustine for any exclusivity-protected indication starting on the date of Bendeka's approval for seven years, i.e., from December 7, 2015 until December 7, 2022, unless a sponsor establishes clinical superiority or an exception to exclusivity applies."

Both Bendeka and Treanda are approved in the US for the treatment of patients with chronic lymphocytic leukemia and patients with indolent B-cell non-Hodgkin’s lymphoma that has progressed during or within six months of treatment with rituximab or a rituximab-containing regimen.

According to an Eagle SEC filing Friday, FDA's decision in favor of the company ensures that no bendamustine product (including generic versions of Bendeka and Treanda) may launch in the US until that date set by FDA -- 7 December 2022. 

In making its decision, FDA explained how its hands were tied by the court's decision. "If Bendeka had been clinically superior to Treanda, its exclusivity would not have blocked ANDAs [abbreviated new drug applications] referencing Treanda. Now that it has obtained exclusivity pursuant to a court order without establishing clinical superiority to Treanda, even though it is not a different drug from the previously approved drug, Treanda, its exclusivity extends to block any drug for the same active moiety."

Generic versions of Treanda, meanwhile, were poised to enter the market in November 2019, Eagle said.

Bernstein analyst Ronny Gal took issue with the FDA’s decision, noting to investors: “This is poor performance by FDA which shows that even in the Gottlieb era, the risk-averse bureaucracy can get lost in its own maze of regulations. The illogical decision will cost the public some $3B in added costs.”

However, one of the generic companies seeking to bring its own bendamustine product to market may sue over the decision, Gal noted.

Teva Pharmaceuticals, Eagle’s partner, also said FDA has appealed the district court’s decision from last summer. However, barring a reversal by the appellate court, drug applications referencing Bendeka also will not be approved by FDA until the orphan drug exclusivity expires in December 2022.

Gal said that there are at least five generic companies pursuing generic versions of Bendeka and Treanda.