Why are the generics not pushing the prices down more? All they have to do to replicate this drug is to HPLC it to find out the chemicals and amounts, and it is so easy to inject a 5 year old can do it.
These generics should be pushing the price down way more. I don't understand why remicade doesn't have 5 other generics.
This is incorrect. Biologics such as Remicade and Humira are antibodies which are large and complex proteins that are grown in either living cells or cell-free protein expression systems. They are not simple molecules that can be easily sorted out on an HPLC and synthesized in a flask.
To give some idea of the relative size and complexities we are talking about here let's consider two different IBD drugs: azathioprine and Remicade. Aza is a typical small-molecule drug with a molecular weight of 277. Remicade is a typical protein biologic drug with a molecular weight of approximately 149,000. Remicade is therefore about 538 times the size of azathioprine. Since it's also an antibody Humira is close to the same size as Remicade.
In part this difference in degrees of size and complexity is why the FDA invented the whole concept of "biosimilar" - because it's easy to prove that your generic copy of azathioprine is chemically identical to the original. But for a molecule over 500 times larger it becomes impossible to prove that every one of the thousands of carbon, nitrogen and, hydrogen atoms that comprise your candidate generic copy of Remicade molecule is put together in exactly the same chemical arrangement as the original. If FDA had not come up with the biosimilar category there would never be any generic versions of biologic drugs at all. It would be an impossible task.
Thus, instead of proving that your generic is identical, drug makers only have to prove it is "similar." But even proving similar is still a huge and expensive undertaking. The FDA tends to be a very skeptical and risk-averse organization. They require a lot of data to be convinced of anything, especially with serious diseases like Crohn's and potentially risky drugs like injectables. Add that to the huge technical hurdles of making the drug in the first place and you get some idea why the biosimilars are only a little cheaper than the originals - because even though it's a copy, it's still a very long and difficult process to make, test, and validate that the large, complex, generic has the same or very similar structure, function, and biological effects as the original. If it were cheap and easy to make and cheap and easy to get through the FDA there would be dozens of generic Remicades already.