Update on the PEGylation Wars: Schering Plough vs Roche
There are currently two injectable products on the market that are used to treat chronic Hepatitis C infections. Both products, PEG-INTRON (Schering Plough) and Pegasys (Roche) are PEGylated versions of the cytokine interferon-alpha that are used in combination with ribavarin (an orally-delivered small molecule drug) to treat patients infected with Hepatitis C virus.
PEG-INTRON (peginterferon alpha-2b) was co-developed by Schering Plough and Enzon in the early 1990s and brought to market in 2000. Pegasys (peginterferon alpha-2a) , which use a different chemistry to attach PEG to interferon-alpha, was approved in early 2002 and quickly supplanted PEG-INTRON as a treatment of choice for Hepatitis C infections. Pegasys also gained approval in 2005 to treat chronic Hepatitis B infections.
The knock on PEG-INTRON was that it appeared to lose potency in liquid form (a claim that has always been denied by Schering and Enzon). Nevertheless, PEG-INTRON was supplied to patients as a sterile powder which had to be reconstituted prior to injection. In contrast, Pegasys was supplied in liquid form in pre-filled self injection pens to infected patients. This was possible because the PEG chemistry used to create Pegasys was found to be extremely stable (as compared with PEG-Intron?) in liquid form. Although there appeared to be no real differences in efficacy between PEG-INTRON and Pegasys to treat Hepatitis C infections, patients tended to prefer Pegasys over PEG-INTRON because it was easier and more convenient to use.
Schering Plough has been struggling for the past 5 years or so to recapture the market share that it lost following Pegasys’ introduction in late 2002. To that end, in 2003 the company received FDA approval for a pre-filled injection pen to administer PEG-INTRON. Further, to dispel any rumors regarding PEG-Intron’s efficacy relative to Pegasys, Schering decided to conduct two large head-to-head clinical studies that compared PEG-Intron or Pegasys in combination with ribavarin as treatments for Hepatitis C patients. Today, Schering-Plough announced the results of the first of these two large scale clinical studies called IDEAL. The results from the IDEAL study showed that PEG-Intron was just as effective as Pegasys for treating patients with Hepatitis C. Further, it appeared that fewer patients taking PEG-INTRON relapsed after treatment.
It is not clear whether Schering will win the war but the company certainly appears to have won this most recent skirmish!
Until next time…
Good Luck and Good Job Hunting (try Schering Plough)!!!!!!!!!
