I have recently signed up for the StemCellPatents.com weekly newsletter, and it is great to keep updated on all the patents that get issued in regenerative medicine. In the most recent newletter, they reported on two patents that issued last week that strengthen Celgene’s patent estate in adult stem cells. Celgene got into the stem cell business in late 2002 when they aquired Anthrogenesis (also see Celgene’s History graffic from their website below). Anthrogenesis had technology for harvesting placenta-derived stem cells from post-birth placentas, as well as biomaterial fabrics that were also placenta-derived. Pre-Celgene, Anthrogenesis was looking for ways to utilize their cells and biomaterials therapeutically. The patent applications around the Anthrogenesis technology are beginning to issue, so Celgene must be patting themselves on the back right now. While looking at these two patents, I also found 2 others that recently issued, as well as a host of pending applications.

The History of Celgene – graphic, with minor modifications, from http://www.Celgene.com

So far, it looks like four of the patents around Anthrogenesis’ technology have issued. Click on the thumbnail to the left if you want more details. The claims for patent US7311905 are centered around a cell composition that has been isolated by a particular method. The primary claim of the patent reads:

1. A composition comprising human stem or progenitor cells and isolated human placental stem cells that are SH2⁺, SH3⁺, SH4⁺ and OCT-4⁺, wherein said placental stem cells are obtained from a placenta that has been drained of cord blood and flushed to remove residual blood.

In general, composition claims are the strongest when they are not tied to a process, but it looks like these claims were limited during prosecution to include that last part “wherein said placental stem cells are obtained from a placenta that has been drained of cord blood and flushed to remove residual blood”. That means if I could figure out how to isolate those exact cells without draining the cord blood first or flushing to remove the blood, I could get around this patent. Therefore, Celgene won’t be able to prevent other placenta companies from using the same cells (using this patent), as long as those cells are isolated outside of this method. I am not familiar with other placenta-derived stem cell patents that have good composition claims that would prevent Celgene from having freedom to operate (a very good thing for Celgene), but that doesn’t mean there aren’t any out there. It is also possible that Celgene has access to earlier patents that provide them full freedom to operate with these cells.

The other 3 issued patents, and their multiple pending applications, outline a nice claim strategy around the placenta stem cell technology. The portfolio is organized around:

1. the starting material (perfused placentas),
2. methods to perfuse the placentas and collect the cells,
3. compositions around the cells that come out of the process (although I am sure they are arguing for pure composition claims),
4. biomaterials that are derived from placentas, and
5. “methods of use” claims where they are claiming the use of their biomaterials and cells for immunomodulation (think Osiris’ GVHD product) and treating diseases such as critical limb ischemia and cancer.

It looks like Celgene is getting some traction with their stem cell technology, but I am a little surprised with their lack of (public) clinical activity. I have been looking for announcements of clinical trials, but Celgene has been very quiet on what is going on with their Cell Therapuetics subsidiary. You can tell with the most recent published patent applications that they are continuing to push the technology forward, and they recently gave a presentation at the last WillBio conference that I unfortunately couldn’t attend. I look forward to hearing more about where they are going with the technology.

Note: I am a shareholder in Celgene.