Free Republic
Browse · Search
General/Chat
Topics · Post Article

Skip to comments.

New direction for flu drugs
Chemistry World ^ | 21 February 2013 | James Urquhart

Posted on 02/23/2013 11:14:06 PM PST by neverdem

An international team of researchers has developed a new class of anti-flu drug that could prevent new virus strains developing resistance and help control future pandemics while more effective vaccines are prepared. Each year, flu viruses cause up to five million cases of severe illness worldwide, resulting in up to 500 000 deaths.

The preferred drug treatments for flu – neuraminidase inhibitors including Tamiflu (oseltamivir) and Relenza (zanamivir) – treat infection by stopping the viral surface enzyme neuraminidase from interacting with its natural substrate, sialic acid. It is this interaction that releases the virus from an infected cell and allows it to spread to other cells.

The problem, however, is that influenza viruses are constantly evolving and therefore strains have emerged that are resistant to these drugs. There is therefore a pressing need for new drugs that work in different ways.

Now, researchers in Canada, Australia and the UK have developed a new class of mechanism-based covalent compounds that inhibit neuraminidase in such a way that they think it could reduce the chances of flu viruses developing resistance.

'Our plan was to design a molecule that was as close as possible in structure to the natural substrate (sialic acid), because viruses will develop resistance most readily against drugs that radically differ in structure from the natural substrate,' says Stephen Withers, who led the study at the University of British Columbia, Vancouver.

Structure of new flu drug candidates

The drugs mimic the sialic acid target of neuraminidase, then covalently attach to block its activity © AAAS

The team describe the new compounds as ‘Trojan horses’ because they look very much like the natural substrate. But once acted upon by neuraminidase they form a very long-lived covalent intermediate species with the enzyme, thereby blocking the active site from the binding of the natural substrate.

The upshot is the virus cannot mutate its key catalytic residues to stop this covalent attachment. 'If it did so, it would no longer be able to carry out its normal function. Consequently we believe that development of resistance will be much slower, if it occurs at all,' explains Withers.

The compounds have been tested on infected mice, which were completely protected against lethal infection. 'We have already shown that they work well against viral strains that are resistant to Tamiflu or Relenza. We are now embarking on tests to probe whether resistant mutations ever develop against our compounds,' says Withers.

William DeGrado, a pharmaceutical chemist at the University of California, San Francisco, US agrees that this mechanism-based covalent strategy could offer a reduced risk of developing resistance as compared to other existing neuraminidase inhibitors. 'It will be interesting to see whether robust oral bioavailibility can be obtained within this new class of mechanism-based inhibitors,' he comments.

'Oral bioavailability is something we are working on through a pro-drug approach,' says Withers. 'I am very optimistic we can do it.'

References

J-H Kim et al, Science, 2013, DOI: 10.1126/science.1232552




TOPICS: Health/Medicine; Science
KEYWORDS: influenza; microbiology; virology

1 posted on 02/23/2013 11:14:13 PM PST by neverdem
[ Post Reply | Private Reply | View Replies]

To: neverdem

obamacare will not permit this. Too many old people will not die as he is prescibing and this will continue their miserble lives.


2 posted on 02/23/2013 11:22:02 PM PST by DISCO
[ Post Reply | Private Reply | To 1 | View Replies]

To: Mother Abigail; EBH; vetvetdoug; Smokin' Joe; Global2010; Battle Axe; null and void; ...
A Passport to Nanomedicine Success

FReepmail me if you want on or off my combined microbiology/immunology ping list.

3 posted on 02/23/2013 11:25:11 PM PST by neverdem ( Xin loi min oi)
[ Post Reply | Private Reply | To 1 | View Replies]

To: 2ndreconmarine; Fitzcarraldo; Covenantor; Mother Abigail; EBH; Dog Gone; ...

Ping... (Thanks, neverdem)


4 posted on 02/24/2013 1:45:39 AM PST by Smokin' Joe (How often God must weep at humans' folly. Stand fast. God knows what He is doing)
[ Post Reply | Private Reply | To 1 | View Replies]

To: 2ndreconmarine; Fitzcarraldo; Covenantor; Mother Abigail; EBH; Dog Gone; ...

Ping... (Thanks, neverdem)


5 posted on 02/24/2013 1:46:38 AM PST by Smokin' Joe (How often God must weep at humans' folly. Stand fast. God knows what He is doing)
[ Post Reply | Private Reply | To 1 | View Replies]

>> The problem, however, is that influenza viruses are constantly evolving and therefore strains have emerged that are resistant to these drugs.

I’m not contributing to that problem.


6 posted on 02/24/2013 2:19:29 AM PST by Gene Eric (The Palin Doctrine.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: neverdem

Good article.

Never had a flu shot. I must have the immune system of an elephant. Everyone in the house had flu last month but me. Sick all the time as a kid though. Another mystery.


7 posted on 02/24/2013 2:29:28 AM PST by poobear (Socialism in the minds of the elites, is a con-game for the serfs, nothing more.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: neverdem

Iatrogenesis

http://en.wikipedia.org/wiki/Iatrogenesis

Never had a flu shot and most likely never will. I see no compelling reason to screw around with a perfectly working immune system for no reason.


8 posted on 02/24/2013 2:34:51 AM PST by Fzob (In matters of style, swim with the current; in matters of principle, stand like a rock. Jefferson)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Fzob

Plus you never know what new “attributes” they may introduce to your body in the form of a flu shot nowadays. In years past thiswoukd be tin foil hat category but not anymore with the AC sitting on his throne / teeing offa t the nearest golf course. I’d like to see Jeus come back and wrap a 9 iron around his scrawny neck but that wouldn’t be very Christian of me would it? Oh well at least I get some points for honesty...sigh...


9 posted on 02/24/2013 4:34:23 AM PST by jsanders2001
[ Post Reply | Private Reply | To 8 | View Replies]

To: Fzob

Plus you never know what new “attributes” they may introduce to your body in the form of a flu shot nowadays. In years past thiswoukd be tin foil hat category but not anymore with the AC sitting on his throne / teeing off at the nearest golf course. I’d like to see Jeus come back and wrap a 9 iron around his scrawny neck but that wouldn’t be very Christian of me would it? Oh well at least I get some points for honesty...sigh...


10 posted on 02/24/2013 4:34:52 AM PST by jsanders2001
[ Post Reply | Private Reply | To 8 | View Replies]

To: poobear

My one and only flu shot was during the Ford administration. I figured since I commuted by NYC subway and worked as a field tech, in and out of many different offices, it was a good idea. Got deathly ill for a week. Since then I’ve had the flu on occassion, but nothing so bad as when I got that shot. This year, at 68, I had a two day fever, a cough and aches. One more day of weakness and I was back to normal.

Conclusion....NO flu shots for Roccus!


11 posted on 02/24/2013 5:05:58 AM PST by Roccus
[ Post Reply | Private Reply | To 7 | View Replies]

To: Roccus

Good decision. :)


12 posted on 02/24/2013 5:15:20 AM PST by poobear (Socialism in the minds of the elites, is a con-game for the serfs, nothing more.)
[ Post Reply | Private Reply | To 11 | View Replies]

To: Roccus

No flu shots for me either.


13 posted on 02/24/2013 5:19:00 AM PST by bmwcyle (People who do not study history are destine to believe really ignorant statements.)
[ Post Reply | Private Reply | To 11 | View Replies]

To: Fzob
Never had a flu shot and most likely never will. I see no compelling reason to screw around with a perfectly working immune system for no reason.

You gain the most benefit from a flu shot when your immune system is, in fact, working perfectly. A shot "educates" your immune system by "showing" it what the pathogen "looks" like; later, when your immune system encounters that pathogen, it is ready to protect you.

If your immune system does not work perfectly, then a vaccine might not "educate" it very well and the pathogen can still make you sick. Maybe not quite as sick as you would become without the vaccine, but still sick.

14 posted on 02/24/2013 6:16:04 AM PST by exDemMom (Now that I've finally accepted that I'm living a bad hair life, I'm more at peace with the world.)
[ Post Reply | Private Reply | To 8 | View Replies]

To: neverdem; Smokin' Joe

Thanks for posting this and for the ping! I will have to look up the original research report; I find that articles targeted for lay-people leave out crucial details.


15 posted on 02/24/2013 6:19:09 AM PST by exDemMom (Now that I've finally accepted that I'm living a bad hair life, I'm more at peace with the world.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: exDemMom
You gain the most benefit from a flu shot when your immune system is, in fact, working perfectly. A shot "educates" your immune system by "showing" it what the pathogen "looks" like; later, when your immune system encounters that pathogen, it is ready to protect you. If your immune system does not work perfectly, then a vaccine might not "educate" it very well and the pathogen can still make you sick. Maybe not quite as sick as you would become without the vaccine, but still sick.

Don't forget the millions of flu strains out there. If you get vaccinated for the wrong strain you won't necessarily have a strong cross immunity to the unlike strain. You are certainly better off with it(the vaccination) than without it but CDC has guessed wrong in the past.

16 posted on 02/24/2013 6:25:13 AM PST by Cowman (How can the IRS seize property without a warrant if the 4th amendment still stands?)
[ Post Reply | Private Reply | To 14 | View Replies]

To: Roccus
Back in the dark ages (Ford administration) flu shots contained a live virus (it made you sick) that has not been the case for many years.

As we age catching the flu is more dangerous because it can leave you with pneumonia which can easily kill you.

I have not had the flu since I began taking flu shots every year for about 20 years. I don't miss my flu shot and you should reconsider yours.

17 posted on 02/24/2013 6:35:01 AM PST by Ditter
[ Post Reply | Private Reply | To 11 | View Replies]

To: Roccus
My one and only flu shot was during the Ford administration. I figured since I commuted by NYC subway and worked as a field tech, in and out of many different offices, it was a good idea. Got deathly ill for a week. Since then I’ve had the flu on occassion, but nothing so bad as when I got that shot. This year, at 68, I had a two day fever, a cough and aches. One more day of weakness and I was back to normal.

There are a lot of possibilities here.

Did you have an allergic reaction to that shot? Were you exposed to the flu before the shot had time to work (it takes about 2 weeks to develop immunity following a shot)? Did you catch a flu or flu-like illness that was not contained in the shot?

For people who are allergic to the flu shot, there are now flu shots available that are not made in eggs.

The flu vaccine can only protect against 3 (4, in some newer vaccines) kinds of flu. But there are many kinds of flu. Whether or not the shot will protect you depends on how similar the flu you are exposed to is to the (dead) flu contained in the shot.

At your age, the immune system is becoming weak. People over the age of 60 are especially prone to influenza and its complications. One common complication is secondary infections; your body's fight against the influenza virus leaves you susceptible to bacterial infection.

18 posted on 02/24/2013 6:36:12 AM PST by exDemMom (Now that I've finally accepted that I'm living a bad hair life, I'm more at peace with the world.)
[ Post Reply | Private Reply | To 11 | View Replies]

To: Roccus
Back in the dark ages (Ford administration) flu shots contained a live virus (it made you sick) that has not been the case for many years.

As we age catching the flu is more dangerous because it can leave you with pneumonia which can easily kill you.

I have not had the flu since I began taking flu shots every year for about 20 years. I don't miss my flu shot and you should reconsider yours.

19 posted on 02/24/2013 6:39:37 AM PST by Ditter
[ Post Reply | Private Reply | To 11 | View Replies]

To: neverdem

http://www.freerepublic.com/focus/f-chat/1929828/posts


20 posted on 02/24/2013 6:56:08 AM PST by bert ((K.E. N.P. N.C. +12 .....The fairest Deduction to be reduced is the Standard Deduction)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Smokin' Joe

Thanks for the ping.


21 posted on 02/24/2013 7:16:04 AM PST by GOPJ (To be free is to own one's risk - Jonathan Levy)
[ Post Reply | Private Reply | To 5 | View Replies]

To: DISCO
obamacare will not permit this. Too many old people will not die as he is prescibing and this will continue their miserble lives.

Should be:

obamacare will not permit this for ordinary citizens. Too many old people will not die as he is prescibing and this will continue their miserble lives.

22 posted on 02/24/2013 7:17:41 AM PST by null and void (Gun confiscation enables tyranny. Don't enable tyranny.)
[ Post Reply | Private Reply | To 2 | View Replies]

To: jsanders2001
that wouldn’t be very Christian of me would it?

1) Someone once said "if you don’t have a sword, sell your cloak and buy one."

2) Ask some moneychangers what Christianity can look like...

23 posted on 02/24/2013 7:23:18 AM PST by null and void (Gun confiscation enables tyranny. Don't enable tyranny.)
[ Post Reply | Private Reply | To 10 | View Replies]

To: null and void

Then there’s going to be a lot more tables not only just turned over but chopped up and turned into firewood this time ‘round...lol


24 posted on 02/24/2013 8:02:48 AM PST by jsanders2001
[ Post Reply | Private Reply | To 23 | View Replies]

To: exDemMom

I understand the potential benefits of a flu shot, but I would rather not put myself at risk for no reason. I am 54 years old and perhaps had a bothersome case of the flu 2 or 3 times during my life On the other hand medical treatment especially when not actually needed is pretty risky

From my link above.

Iatrogenesis is a major phenomenon, and a severe risk to patients. A study carried out in 1981 more than one-third of illnesses of patients in a university hospital were iatrogenic, nearly one in ten was considered major, and, in 2% of the patients, the iatrogenic disorder ended in death. Complications were most strongly associated with exposure to drugs and medications.[16] In another study, the main factors leading to problems were inadequate patient evaluation, lack of monitoring and follow-up, and failure to perform necessary tests.[citation needed]

In the United States, figures suggest estimated deaths per year of: [17][18] [19][20]

12,000 due to unnecessary surgery
7,000 due to medication errors in hospitals
20,000 due to other errors in hospitals
80,000 due to nosocomial infections in hospitals
106,000 due to non-error, negative effects of drugs
Based on these figures, iatrogenesis may cause 225,000 deaths per year in the United States (excluding recognizable error).[17]


25 posted on 02/24/2013 8:11:15 AM PST by Fzob (In matters of style, swim with the current; in matters of principle, stand like a rock. Jefferson)
[ Post Reply | Private Reply | To 14 | View Replies]

To: bmwcyle
Never had a flu shot...take d3 daily...can't remember the last time I was sick...it's literally been decades.

Hospitals are the most dangerous place on earth.

26 posted on 02/24/2013 8:16:41 AM PST by who knows what evil? (G-d saved more animals than people on the ark...www.siameserescue.org.)
[ Post Reply | Private Reply | To 13 | View Replies]

To: Fzob
I understand the potential benefits of a flu shot, but I would rather not put myself at risk for no reason. I am 54 years old and perhaps had a bothersome case of the flu 2 or 3 times during my life On the other hand medical treatment especially when not actually needed is pretty risky

You have to weigh the risk vs. the benefit for each procedure separately.

For example, the concern of having iatrogenic complications is reasonable if you are contemplating something like undergoing cosmetic surgery without a clear medical need. However, the risk of complication is extremely low with vaccines (of any kind, not just influenza), making vaccination a very reasonable precaution to take against the real risk of illness, permanent complications, and even death from the diseases they prevent.

Even if you are allergic to eggs, there may not be that much risk with flu vaccines. Recent studies have shown that most people with egg allergies tolerate the vaccines well.

The only other complication that is definitively linked to vaccines is slight pain and tenderness at the injection site, lasting a day or so. I've never had this from a flu shot, but I know people who do have that complication. They still get the shot.

Most strains of flu cause higher levels of mortality of young children (because their immune systems are still developing) and elderly people (because the immune system starts to senesce after about age 60). But even healthy adults and teens succumb to the flu. (An exception was the 1918 or "Spanish flu" which killed a disproportionately high number of young adults.) Flu kills directly, and indirectly by leaving you susceptible to bacterial infections. In many cases, you are already carrying around bacterial pathogens; they are unlikely to cause an infection until your immune system is weakened or a cut allows them to penetrate through the skin. You may have had the flu a couple of times and recovered just fine, but that is no guarantee you'll do as well the next time.

This is hard to say, but one of your best precautions against needing hospitalization (with its risk of iatrogenesis) is to avail yourself of available vaccines.

27 posted on 02/24/2013 1:34:41 PM PST by exDemMom (Now that I've finally accepted that I'm living a bad hair life, I'm more at peace with the world.)
[ Post Reply | Private Reply | To 25 | View Replies]

To: DISCO
Well, screw you, Obama, I don't need your stinkin flu drugs. I don't expect anyone to believe me but we are doing just fine at our house with no drugs and no vaccines.

I wouldn't trade my Vit D, and kombucha for a drug store full of drugs.

A couple of weeks ago, I deliberately went to visit my friend with the flu to test my theory that we are pretty much immune to colds and flu now. She had had the flu vaccine--we won't touch them.

Each night and am. I take a glass of water with 1/2 tsp baking soda and a TBS Braggs vinegar. We do the kombucha and we're going to outlive those who spend their time going to doctors and buying expensive drugs with side effects.

28 posted on 02/24/2013 3:54:06 PM PST by Conservativegreatgrandma (The perfect is the enemy of the good..............Voltaire)
[ Post Reply | Private Reply | To 2 | View Replies]

To: Smokin' Joe

Thanks for the ping!


29 posted on 02/24/2013 8:22:22 PM PST by Alamo-Girl
[ Post Reply | Private Reply | To 4 | View Replies]

To: exDemMom; Ditter

Thank you for your concern, but.... no thanks.


30 posted on 02/25/2013 9:21:29 AM PST by Roccus
[ Post Reply | Private Reply | To 18 | View Replies]

To: neverdem

bookmark


31 posted on 03/02/2013 9:27:04 PM PST by delacoert
[ Post Reply | Private Reply | To 1 | View Replies]

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
General/Chat
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson