Coumadin 5mg availability in Australia

[billD]

The pharmacies I tried in Sydney are not able to supply 5mg Coumadin. There is a supply problem that appears to have been caused by a change in suppliers. The TGA is reporting that the supply issues will not be resolved until July Medicine Shortages Information Initiative)
Have other Coumadin users in experienced this availability issue?
Also, has anyone changed from Coumadin to Marevan? If so, what do i need to be aware of?
The advice is that you should stay with one brand.
BTW, I take 11mg per day and doing this with 2mg tablets for the next 4 months won't be fun and there is a high likelihood that these tablets will quickly end up in short supply if everyone is using them (instead of the 5mg).

Cheers, Bill

 

[pellicle]

Good morning Bill

I take Marevan, and I had an issue with being not able to obtain the 1mg tablets at one stage which I needed to make my dose up conveniently to 6.5mg daily without engaging in too much giggery pokery.

For us as the PBS makes these all about the same price (1, 3 and 5mg in my case) it no more or less costly for me to have needed extra bottles to make my dose (PBS).

I believe this is a temporary situation caused by the various global supply issues, but as the War (not special operation) waged by Russia in Ukraine is driving the next round of "the system hits its just in time managed edges".

It is unwise without testing to change brands, this has been discussed before here many times. The short answer however is that the Australian government recognises this (even if a member or two here doesn't) and that is why your script is not for "any coumarin" but for your brand. So a doctor will be needed for you to change brands.

In theory this should not be needed, but actual evidence does not support the theory (I have my own theory on why that is so), but this article makes clear why (Note the source is the Australian pharmacy organisation hosted by the Australian Commission on Safety and Quality in Health Care, not just some random poster on the internet).

https://www.nps.org.au/australian-prescriber/articles/bioequivalence-of-coumadin-and-marevan
Key point in that is this paragaraph segment

Our experience with a single patient indicates that the brands are not bioequivalent. The patient was on a dose of 4 mg of warfarin, initially provided by 1 x 1 mg, 1 x 3 mg Marevan, and had an INR = 2.7. Upon completion of that supply, the patient was given Coumadin (2 x 2 mg) and subsequently presented with an INR = 4.4. After questioning, we established that the patient was well and that brand substitution had occurred. The Coumadin was stopped and replaced with Marevan and the INR returned to an acceptable level. It was fortunate that the initial INR was not higher as the brand substitution could easily have placed the patient at risk of haemorrhage. It is reasonable to suggest from this patient that the brands are not bioequivalent. There is a report of similar instability in 15 patients who had their brand of warfarin substituted.4​

So I strongly advise you to "work around this" not just "mix n match"

My theory is that the racemic mix isn't always perfectly racemic and that the factors of S and R entaniomers of warfarin are key to understanding of this. S is approximately 5 times more potent than R but R has about double the half life, which drastically changes what the outcomes are in obtaining a steady state. I am discussing this exact point in my book on managing INR but that's not yet completed (watch this space).

Enantiomers is a chemistry term for mirror images of compounds but like gloves they only fit one hand, they have therefore entirely different actions within the body.

S is so named after the latin for Left as is R for Right

HTH

 

[dick0236]

It is my understanding that Bristol, Myers, Squibb, the owner of the drug Coumadin discontinued the manufacture of the Brand Coumadin last year........due to a decline in the demand for that brand name drug. I would make the switch to Marevan, Warfarin, or other warfarin-based anti-coagulant as the inventory of remaining Coumadin continues to decline.

I made the switch from Coumadin to Warfarin (Taro brand) several years ago with no change to my INR. You are correct that once you find a replacement warfarin.......stay with that brand.

 

[pellicle]

PS: @billD , if you've still got the urge to know more see my post in this thread (direct link below)
https://www.valvereplacement.org/th...-thinners-mechanical-valve.887935/post-904322
Best Wishes

 

[pellicle]

It is my understanding that Bristol, Myers, Squibb, the owner of the drug Coumadin discontinued the manufacture of the Brand Coumadin last year..

to my knowledge its still marketed here in Australia provided by Jantoven ... amusingly the Australian Prescriber says this:

https://www.nps.org.au/australian-prescriber/articles/warfarin-brands

... In Australia we have two brands − Coumadin and Marevan. Both are manufactured by Aspen Pharmaceuticals, and are available in different strengths and tablet colours.​

which is even more interesting given the above post on metabolic differences within a patient (s). This suggests to me that there are indeed various "formulations" of "racemic" if not that there are other factors changing metabolic reactions that are inherent in the various formulations.

 

[MdaPA]

It is my understanding that Bristol, Myers, Squibb, the owner of the drug Coumadin discontinued the manufacture of the Brand Coumadin last year........due to a decline in the demand for that brand name drug.

Perhaps this is the reason for the price increase of 250% I'm seeing for my wife's Warfarin Rx from last year (from $11.96 to $42 for a 90-day supply/pills of 5mg)?

 

[pellicle]

(from $11.96 to $42 for a 90-day supply/pills of 5mg)?

just for reference a bottle of 50 5mg is about AU$20 (in Australia) ... I never think of them in terms of "days supply" but as there are about 30 days in a month and I usually need a 5mg and (some combination of one or a whole of either) a 3 or a 1mg I often need two bottles each time

out of interest how much is either of the "alternatives" like rivaroxaban, apixaban or edoxaban (which are not validly usable for valve related ACT anyway, but just pretending)

 

[billD]

Found a small pharmacy with 5mg Coumadin. Hopefully the current supply issues are resolved wthin the next couple of months.
I didn't want to change brands but this may have been the option if supplies of Coumadin weren't available.
Thanks everyone for your informative responses. I am still getting used to the vagaries of warfarin therapy. The factors influencing my INR readings seem to include exercise intensity, stress and to a lesser extent diet. With self-testing I am staying in range for over 90% of the time

 

[MdaPA]

I never think of them in terms of "days supply" but as there are about 30 days in a month

Unless it's a one-time thing (e.g. antibiotics), maintenance/on-going medications are normally sold in the U.S. as a 30-day or 90-day supply. Of course, the Rx can be written with more than 1 pill per day (e.g. 180, 1 mg tablets of warfarin in a 90-day supply.)

out of interest how much is either of the "alternatives" like rivaroxaban, apixaban or edoxaban (which are not validly usable for valve related ACT anyway, but just pretending)

www.goodrx.com
Here is a "good" site for finding local drug prices here in the U.S (not sure if you can use in other locations/countries). Simply search on the name of the drug and enter a U.S. zip code (you can try "19067" for example) and you will get a list of places to buy from with their corresponding price. Prices will naturally vary depending on if it's a stand-alone pharmacy, a mail order facility, wholesale club, if there is a coupon, etc. These prices are also excluding any Rx insurance you may have.

e.g. the price of a 90-day supply of Warfarin (5mg) through my wife's Rx supplier is U.S. $42 and her insurance pays 75% of this cost so her out-of-pocket or co-pay is $10.50.

 

[tom in MO]

Wow there's a lot of conjecture here!

I checked the United States Pharmacopeia (I have access through my job). The USP tests for warfarin used as an active pharmaceutical ingredient (API) does not include a test for chiral purity. If chiral purity is important it would be controlled and if variable it would be tested to assure compliance to specifications. Often chiral purity of a API is controlled by the chiral purity of a starting material. In the US, if chiral purity is important, bioequivalence testing would require its evaluation for any new maker of warfarin and related drug products to be able to market the drug in the US. This may not apply to Australia.

I use generic warfarin. Personally, I have not had any problems when my generic warfarin has switched suppliers. My prescribing doctor has not said the manufacturer needs to be monitored. Even if you stay with one manufacturer of the drug, they can change the active pharmaceutical ingredient supplier and one would never know. FDA regulates who can manufacture the API and the drug product.

My warfarin through Blue Cross Blue Shield is a <$10 copay for 30-90 tablets. The doctor's nurse asks me how many tablets I want the script written for. I keep about a 2 month supply on hand for all drugs in case we have to "shelter in place" again

 

[carolinemc]

Wow there's a lot of conjecture here!

I checked the United States Pharmacopeia (I have access through my job). The USP tests for warfarin used as an active pharmaceutical ingredient (API) does not include a test for chiral purity. If chiral purity is important it would be controlled and if variable it would be tested to assure compliance to specifications. Often chiral purity of a API is controlled by the chiral purity of a starting material. In the US, if chiral purity is important, bioequivalence testing would require its evaluation for any new maker of warfarin and related drug products to be able to market the drug in the US. This may not apply to Australia.

I use generic warfarin. Personally, I have not had any problems when my generic warfarin has switched suppliers. My prescribing doctor has not said the manufacturer needs to be monitored. Even if you stay with one manufacturer of the drug, they can change the active pharmaceutical ingredient supplier and one would never know. FDA regulates who can manufacture the API and the drug product.

My warfarin through Blue Cross Blue Shield is a <$10 copay for 30-90 tablets. The doctor's nurse asks me how many tablets I want the script written for. I keep about a 2 month supply on hand for all drugs in case we have to "shelter in place" again

They have stopped selling Coumadin in the USA some time ago. I believe it was the copyright ran out. I pay $4.00 for it through a new med cover with Medicare. I am now getting 30 to 90 day for that low price. i love the 90 day due to in the winter, I also have problems getting out in my city in the snow and ice.

 

[aussiemember]

Hi all,

Thanks for this very informative thread. There was an article in the Age (newspaper) on line this morning so I went out to my local chemist and was able to get their last bottle of 5 mg. Seems to be plenty of the 2 mg around so can just substitute that if needed. I was interested to read Pellicle that you are now on Marevan as I hadn't heard there was another Warfarin substitute here in Australia.

 

[pellicle]

Hi

Pellicle that you are now on Marevan as I hadn't heard there was another Warfarin substitute here in Australia.

yep

been on it since November 2011

Conveniently its the main brand in Finland too ... which I had no thought about at all till I went back there in 2013

 

[aussiemember]

Hi


yep
View attachment 889135

been on it since November 2011

Conveniently its the main brand in Finland too ... which I had no thought about at all till I went back there in 2013

Thanks so much for that and for the picture of what it looks like. Very reassuring to know that I can get that as a substitute - I realise there may be variations in INR with the change but as I have been home testing for 14 years that doesn't concern me - once again this site and the wonderful members on it prove invaluable

 

[ATHENS1964]

For the reason that at any moment there may be a shortage, I have that in stock for about a year, I also don't have everything in one place, I have some boxes at work, some at home and some at friends' houses.
warfarine and acetocoumarol are taken today by those who have a mechanical valve Warfarin was also taken by those who had AFIB, who were a large percentage of the elderly. It is estimated that one in four middle-aged people will suffer from atrial fibrillation during their lifetime.
However, these patients are now taking the new and much more expensive pills, and the companies will raise the prices of our cheap pills, as well as the INR strips.
Another issue is what happens in case we are in another country and we lose our pills or they are destroyed, if any forum member is in Greece and faces a problem with pills or INR strips he can contact me so I can help him find them.

 

[pellicle]

Very reassuring to know that I can get that as a substitute

well you sort of can't without consulting your Dr and getting a different script for it because of the INR changes, but if you can reassure your Dr about it then it'll be no problem. As long as we don't start getting shortages of CoaguChek strips ;-)

 

[LondonAndy]

Just been catching up on this issue, which currently appears to be specific to Australia. I have a Google Alert setup for Warfarin news stories, and the Sydney Morning Herald suggests supply issues will continue until July at least, and in some areas supply is so bad they are resorting to Heparin injections.

 

[pellicle]

Hi

I'll nip into town tomorrow and see what the situation is like for Marevan

its troubling but some small part of me suspects incompetence in the part of journalists

Just been catching up on this issue, which currently appears to be specific to Australia. I have a Google Alert setup for Warfarin news stories, and the Sydney Morning Herald suggests supply issues will continue until July at least, and in some areas supply is so bad they are resorting to Heparin injections.

not least because SMH ...

 

[aussiemember]

well you sort of can't without consulting your Dr and getting a different script for it because of the INR changes, but if you can reassure your Dr about it then it'll be no problem. As long as we don't start getting shortages of CoaguChek strips ;-)

I‘d be lost without my strips - much better than regular visits to pathology

 

[aussiemember]

member

One year is impressive - I always keep some extra but after this will be even more careful