This article is provided to FT.com readers by Pharmawire—a news service focused on providing insight into the most price sensitive issues in the global pharmaceutical market. www.pharmawire.com
--------------------------------------------------------------------------------------------------------
Insmed has indeed demonstrated bioequivalency for its biogeneric white blood booster, but the FDA is unlikely to approve the drug until a regulatory pathway is in place, legal and scientific sources told Pharmawire, drawing a distinction between the science and politics that are shaping the biosimilar debate.
There is currently no FDA approval process in place for approving generic versions of protein-based drugs. Nevertheless, the Virginia-based company is pressing on in developing biogeneric versions of Amgen’s blockbuster G-CSF drugs Neupogen and Neulasta, which treat a low white blood cell condition called neutropenia. The company today announced that tests have shown that its INS-19 product is bioequivalent to reference product Neupogen.
In an interview , president and CEO Dr Geoffrey Allan confirmed that the company will likely need to conduct additional tests in order to gain FDA approval - including immunogenicity studies. The company is requesting a meeting with regulators to plan Phase III studies as well as Phase I bioequivalence studies for INS-20, a biogeneric of Neulasta.
Insmed compared blood samples from 32 volunteers who received first one drug and then, after a washout period, the other. Allan noted that the company performed the same test used to determine bioequivalence for a small molecule.
Narinder Banait, a partner at law firm Fenwick & West, noted that the FDA has not issued any guidance to companies looking to market biogeneric products. ”The study design appears to be good, and the results are good as well,” he said. ”However, I do not believe the FDA will accept the data because it does not have the regulatory authority yet. Biologics do not fall under the Hatch-Waxman Act, so showing bioequivalency will not allow Insmed to market a generic G-CSF product.”
Neupogen was approved under the Public Health Services Act, which does not have an avenue for generic approval. ”It seems like they’re taking a shot in the dark,” Banait said.
Yet he stressed that his reservations were not with the data itself, which he said could be ”used as evidence” that biogenerics can be bioequivalent to innovator products.
A legal source on the Hill noted that European regulators have already answered the question of how to determine bioequivalence - and the debate is no longer about science. The source added that the European approval model is based on the FDA’s own comparability standards for biologics.
”Everyone has admitted the science is possible,” the source said, adding that data exclusivity issues - how long generics makers will need to wait before they can use an innovator’s clinical data in their own dossier - are holding up the legislation in Congress. ”You’re essentially buying a pathway with exclusivity.”
European regulators currently require a level of assessment and length of assessment for biogenerics that is ”in the same league” as new chemical entities - but that the generics industry is still grappling with ”fear, uncertainty and doubt,” Dr Sandy Eisen, chief medical officer at Teva Europe, told this news service in April.
”No one can dismiss the potential for immunogenic concerns; this is not something that is peculiar to biosimilars,” he said. But he noted, ”We have a lot of experience in monitoring and testing for it post-marketing.”
Allan expressed confidence that the US would pass a regulatory pathway before the product comes up for review over the next four years. He added that G-CSF is not a very immunogenic product, and immunogenicity tests are not expensive to perform. He placed the cost of development program as USD 30m - 40m.
The legal source noted that Insmed’s optimism is not misplaced, but emphasized that the FDA is torn between its aversion to risk and a desire to catch up to Europe. ”Given the safety environment, it’s going to come down to quality of data,” the source said. ”If they’ve got good data, then irrespective of the pathway … they’re going to be a step ahead.”
Insmed has a market cap of USD 56m. Amgen’s market cap is 55.86bn.
--------------------------------------------------------------------------------------------------------
For more information or to inquire about a trial please email sales@pharmawire.com or call Americas: +1 212-500-1384 or Europe: + 44 (0)20 7059 6251
