[ RadSafe ] Fwd: Ra-223 Chloride - FDA Approval

[Chris Alston]

Mike

Prostate Ca "feeds" on testosterone.  There is no effective direct
chemotherapy for it (though there are trials).  So, in pts with
distant metastatic disease, palliative care includes depriving the
tumor of as much testosterone as possible.  It can be by means of an
orchiectomy.  There are also chemical means of "castration".  I
imagine that if you can turn off the gonadotropin-releasing hormone
(GnRH, aka LHRH), that will shut down the testes (the kidneys, I don't
know, may be a separate pathway).  But natural selection eventually
has its way, and the tumor cells figure out how to do what they want
to do: proliferate and metastasize, or "divide and conquer", without
the benefit of testosterone.  Caveat: this is all a layman's take on
it.

I am ashamed to say that I don't remember the means of production of
Ra-223.  I'll look around for it.  FYI, it might be in one of the
ACMUI reports on this topic, or in another NRC document.

Cheers
cja


---------- Forwarded message ----------
From: Brennan, Mike  (DOH) <Mike.Brennan at doh.wa.gov>
Date: Wed, May 15, 2013 at 5:30 PM
Subject: Re: [ RadSafe ] Ra-223 Chloride - FDA Approval
To: "The International Radiation Protection (Health Physics)
MailingList" <radsafe at health.phys.iit.edu>


"The U.S. Food and Drug Administration today approved Xofigo (radium Ra
223 dichloride) to treat men with symptomatic late-stage (metastatic)
castration-resistant prostate cancer that has spread to bones but not to
other organs. It is intended for men whose cancer has spread after
receiving medical or surgical therapy to lower testosterone."

Note to self: don't get "castration-resistant prostate cancer".

How do you get Ra 223?  No path leaps out when I look at the chart of
the nuclides.

-----Original Message-----
From: radsafe-bounces at health.phys.iit.edu
[mailto:radsafe-bounces at health.phys.iit.edu] On Behalf Of Chris Alston
Sent: Wednesday, May 15, 2013 2:03 PM
To: The International Radiation Protection (Health Physics) Mailing List
Subject: [ RadSafe ] Ra-223 Chloride - FDA Approval

Radsafers

Please see:

http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm352363.htm

It is hard to tell from the notice.  But I thought that this drug (did
they change the name from Alpharadin, or is that a competitor still in
IND?) was  in trials for the relief of pain from metastases to bone, and
that, incidentally, the investigators showed that pts had extensions of
life (I hope, sincerely, of decent quality, relatively speaking).  Is it
approved for the latter use, or is the FDA just saying that was why they
fast-tracked it?

Cheers
cja