Today Teva Pharmaceuticals announced the receipt of a Complete Response Letter from the FDA for their Biological Licence Application (BLA) for Neutroval. Neutroval is a treatment to reduce the duration of severe neutropenia and the incidence of febrile neutropenia in patients treated with myelosuppressive chemotherapy for cancer similar to Amgen's Neupogen.
Generic drugs are, of course, copies of original drugs that come to market after a patent expires. Drugs are made from chemical recipes that can be replicated. Biologics, however, come not from chemical recipes, but are instead derived from living cells, which means exact copies are an oxymoron. However, something similar can be made and these are called biosimilars. They are similar, but not the same – like a snowflake.
For a long time there has been a regulatory pathway established for the approval of generic drugs. There has, however, been lacking one for biosimilars. That was until health care reform which, among other things, charged the FDA with a very broad directive to create a pathway and giving the agency a lot of discretion into deciding what that would look like.
There are a huge number of variables that figure into the equation. One of the most important is the issue clinical trials for biosimilars. Some say that there is the potential for enough difference between a biosimilar and the original product to which it is similar (called the innovator product) that mean that clinical trials are necessary to demonstrate both safety and efficacy.
But the appeal of generic drugs is that they are much cheaper than the original drugs and part of that is because the manufacturers don't have to put on new clinical trials -. With biosimilars, if a manufacturer has to go through a set of expensive clinical trials, the cost of bringing the biosimilar to market naturally increases. It also adds to the length of time before approval. Therefore the question of clinical trials is a very important one.
Teva had submitted their BLA for their similar product before the process for biosimilar approval has been clarified. In fact, the FDA is reportedly holding a two-day public meeting about the entire subject in November, putting into action its glacial process for guidance development and rule making. In the meantime, if a manufacturer wants to seek approval, the only way it would seem available would be filing a BLA based on what you have in hand.
And that is the interesting part. According to the very brief update from Teva on the matter, the one thing that perhaps spoke volumes was the fact that new clinical trials was specifically the statement that the FDA was not seeking additional pre-marketing clinical trials prior to approval. That one sentence may be shedding light onto FDA's current thinking, as the November meeting approaches, to the entire matter of additional clinical trials for biosimilars.