FDA Denies Amneal Petition Seeking to Block Generic Versions of Osteoporosis Treatment

Capping a string of recent citizen petition denials, the US Food and Drug Administration (FDA) has rejected Amneal Pharmaceuticals' citizen petition asking the agency to refrain from approving any abbreviated new drug applications (ANDAs) for the blockbuster osteoporosis treatment Forteo (teriparatide).

The decision by FDA was not unexpected and followed recent denials of citizen petitions filed by Novo Nordisk and Allergan.

Bernstein biotech analyst Ronny Gal said in a note to investors in November when Amneal filed the petition, noting that the company was "arguing that without fermentation, the impurity profile will change ... This is very similar to the Novo CP on Liraglutide drugs (mostly Victoza). Both follow on FDA decision that synthetic products are fine."

In its denial of Amneal's citizen petition, FDA pointed to October draft guidance on ANDAs for certain highly purified synthetic peptide products, noting, "The draft guidance proposes that submission of an ANDA for a synthetic peptide that references a peptide of rDNA origin would be generally appropriate if, among other things, the applicant can: (1) show that, for each peptide-related impurity that is found in both the proposed generic synthetic peptide and the RLD, the level of such impurity in the proposed generic synthetic peptide is the same as or lower than that found in the RLD; (2) show that the proposed generic synthetic peptide does not contain any new specified peptiderelated impurity that is more than 0.5 percent of the drug substance; (3) characterize each new specified peptide-related impurity; and (4) justify for each new specified peptide-related impurity that is no more than 0.5 percent of the drug substance why such impurity does not affect the safety of the proposed generic synthetic peptide and does not affect its effectiveness."

Meanwhile, Antares Pharma said its ANDA with Teva Pharmaceuticals is under review at FDA. In Europe, two biosimilars from Stada Arzneimittel and Gedeon Richter have already been approved.

2016 sales of Forteo totaled $1.5 billion in 2016, according to Eli Lilly.