Generic drug maker Sandoz has received the regulatory go-ahead to market growth hormone Omnitrope, and its unprecedented application has ignited debate about whether the approval could open the door for biogenerics.
FDA, for its part, has refrained from calling Omnitrope a "biogeneric," instead preferring the term "follow-on protein." The difference is related to how the drug was approved as well as its "substitutability" at the pharmacy.
Sandoz, which is a division of Novartis, filed a new drug application for Omnitrope; the Office of Generic Drugs did not review the submission, according to Ajaz Hussain, Sandoz's vice president and global head of biopharmaceutical development.
Hussain, who was previously deputy director of FDA's Office of Pharmaceutical Science, noted that the company submitted details of its manufacturing operations as well as studies demonstrating safety, efficacy, and how the drug compares to Pfizer's Genotropin.
"What is different is that [Sandoz received additional] indications without having to do clinical trials in those populations," said Hussain, who described the company's submission as a "hybrid application."
He called FDA's decision a "precedent-setting approval," and noted that Sandoz expects to use this process for other drugs in its pipeline.
Yet not everyone agrees that the approval broke new ground.
Consulting firm Wood Mackenzie noted that Genotropin -- and only a handful of other biologics -- were approved under the Food, Drug, and Cosmetic Act (FDCA), which has a provision for generics. Most biologics were approved under the Public Health Services Act (PHSA), which does not.
"We believe the company has used Omnitrope as a bludgeon to force FDA and Congress into considering ways of approving generic versions of recombinant proteins approved under the PHSA legislation," the report stated. "Until such a pathway becomes available, which is unlikely to happen for several years yet, we believe recombinant protein drugs are safe from generic attack in the US."
Nevertheless, FDA's decision could expand the number of follow-on proteins on the market, according to Robert Bell, president of Drug and Biotechnology Development, a consulting firm. These products include insulin, peptides, calcitonin, and Interferon, which were also approved under the FDCA.
But he questioned whether these biogenerics would see the drastic price reduction that small molecule generics enjoy. Because of labeling differences, pharmacists can't substitute bio-similar Omnitrope for brand name Genotropin -- which means Sandoz must still detail the product.
"There should be a savings that should be passed on to consumers," Bell said. "Right now there's a very high barrier to entry."
Yet Hussain noted that, because biologics are more expensive to produce than small molecules, even a modest price reduction could make a big difference. "The cost savings are not going to be the same compared to small molecules but the dollar value saved can be very significant," he said.
The US has so far lagged behind Europe in establishing a process for approving biogenerics -- but both FDA, through its Critical Path Initiative, and members of Congress have prioritized the issue.