Methadone for cancer? Patent natural compounds?

[Guest guest]

Greetings, Thought the following correspondence would be of interest

to some list members. It's about an assumed obstacles to finding

cancer cures: the inability to patent natural compounds.

==

re: " Methadone joins a long list of molecules that have shown

activity in the lab but will never see the light of day as drugs as

either they were not patentable in the first place (naturally

occuring molecules) or their patient has expired. The list is endless

and includes over the counter compounds such as resveratrol, curcumin

and even tetracycline antibiotics. " - comment from list member.

Hi,

I've heard this reason cited often as the reason natural compounds

are not developed - and believed it for quite a while. But there are

many examples of cancer drugs derived from plants, vincristine and

etoposide to name but two. And many other drugs for other conditions.

Also, those in the field will tell you that the original compounds

often don't have the highest affinity to the target, and need to be

modified to improve activity ,or bioavailability, or decrease

toxicity.

Also, it does seem that patent protection is a challenge for natural

products development, but not an insurmountable obstacle as described

here:

" You cannot patent a natural compound as a structure (but you can

make the simplest semisynthetic analog - and if it was never

disclosed you can stake your claim on it). With a natural compound

you can patent its use, a process of isolation/manufacture, a

specific drug formulation, etc but it is obviously a much weaker

protection. " http://totallysynthetic.com/blog/?p=956

I don't know for sure, but strongly suspect that the so-called

patent obstacle is a false argument used to justify unproven

alternative practices ... the reason this and that natural " cure " is

not FDA approved and never will be. That's not to say nature doesn't

provide useful compounds of course, but I think we should take such

arguments with a grain of salt, particularly when doses and blood

levels are not even accounted for in alt med promotions.

Regarding product development: " Only five in 5,000 compounds that

enter preclinical testing make it to human testing. One of these five

tested in people is approved. " ~ Food and Drug Administration: From

Test Tube to Patient

=

But I wrote to an expert to confirm:

Many things to say here Karl. The highlights would be:

1. Methadone is not a natural product although it binds opiate

receptors - it is a synthetic diphenyl compound developed by the

Nazis in WWII because of fears that opium extract (the source of

morphine and codeine) would be subject to Allied blockade from SE

Asia.

2. Regardless of whether methadone is natural, natural products are

indeed patentable but, as the writer notes, use patents are weaker.

However, there are some cases where strong patents can be used to

protect natural products. Taxol (paclitaxel) is a great example: one

could not extract enough taxol from Pacific yew trees without sending

them (and a species of spotted owl) into extinction. Bob Holton at

Florida State came up with a 5-step synthesis satrated with 10-DAB, a

chemical precursor derived from European yew needles (a renewable

resource). Bristol-Myers Squibb licensed Holton's patented synthesis

for their manufacture of Taxol and Dr, Holton is now a very wealthy

man.

3. I would pay very close attention to the final statement by

Kaufmann from Mayo Clinic - is a MD/PhD who treats cancer

patients and has his own basic science laboratory. Many, many

compounds kill all kinds of cancer cells in flasks (i.e., cell

culture) yet few people (and medical writers) consider that the

concentrations of drug required to do so are either unable to be

achieved in patients and/or are so high as to be even more toxic than

conventional chemotherapy. Hence, Dr. Kaufmann's point is that the

concentrations of methadone required to kill leukemia cells are so,

so high that the patient would be dead from a major side effect of

opiate drugs: respiratory depression (i.e., the patient's breathing

center in the brainstem would be depressed such that one would stop

breathing).

~ Kroll, PhD, cancer pharmacologist at North Carolina Central

University