Shelf life of platelets

[Liz]

Is anyone out there on planet earth keeping platelets in storage for 7 (seven) days?

Thank you

Liz

[David Saikin]

not at this point in time

[Liz]

Am I right in saying that it went back and forth and then the 7 days was a liscened FDA trial for 2 years started in 2008. Do you have the document ref stating that the trial was over?

Thanks

Liz

[David Saikin]

Liz

7 day platelets started in the mid1980's (as I recall) - there was such a problem with reactions (due to bacterial growth) that the FDA determined (prior to 1987) that the product, though viable for 7 days, could only be stored for 5. The current Circular of Information on p43 does say that some 7 day platelel pheresis products may be available if facility producing them is in a post-marketing program which allows for the 7 day product.

[Liz]

What is a post-marketing program?

If I collect apheresis platelets, and I perform the Bacterial culture, can I, according to the agency, store my platelets for 7 days?

Thanks.

[SMW]

Gambro and Fenwal pulled the plug on the Passport Study in January 2008. The Passport Study was a clinical trial that allowed blood centers to label apheresis platelet products with a 7-day expiration if the protocol, which included repeat cultures at product outdate, was followed. I am unaware of any currently approved/active study in the US. When the Circular was revised, the committee attempted to provide information if any new study protocols were initiated.

[Liz]

TRANSFUSION, vol 50, Oct 2010 page 2199 has one study on plasma rich plts.

So does the EU approve of 7 days?

Why did they stop the Passport Study?

thanks

[SMW]

The Passport study was d/c based on the sponsor’s assessment of approximately two year’s of interim data which showed a positive culture rate at day 8 of 2 true positives out of 2,571 tested (rate of 778 per million; 95% CI 94-2807 per million) for SDP that had tested negative on an initial culture after 24 hours of storage. This raised concerns about the possibility of the occurrence of clinically significant septic reactions in recipients of SDP, despite negative initial cultures.

Many of the EU products are pathogen inactivated but this technology is not currently licensed in the US.

[Liz]

Thanks. I think I am gloomy now. When the 7 day study was on did you participate and if so did you have encouraging results.

[Colin Barber]

Liz in the UK NHSBT have a product called extended life platelets which have a 7 day shelf life, these products are usually produced during long bank holidays or when there are acute shortages. They are are screened for bacteria prior to issue.

The NHSBT product portfolio is at: http://hospital.blood.co.uk/library/pdf/components/SPN223_version3.pdf

[Liz]

Dear Colin,

Am I happy or what!

Thank you so much for this info and the ref.!

Liz

[rravkin@aol.com]

Colin,

What kind of testing is used for the screening study?

[Colin Barber]

Rravkin@aol.com,

I am sorry I don't the exact methodology our colleagues in the Blood Service use to test for the presence of bacteria in the packs. They have recently announced that from next year they will roll out bacterial testing of all platelets they issue. If any of the UK NHSBT staff who subscribe to Blood bank talk pick up on this thread they will I am sure be able to answer. The link to changes to platelets is:http://hospital.blood.co.uk/library/pdf/The_Update_Nov_2010.pdf

[Liz]

Colin, exactly what I have been hoping for. Thank you so much for sharing. The reference is very important for back up of one's practice.

Ron, I can see from the document that the UK NHSBT staff perform BactAlert (or similar) culture for Bacterial screening, because they hold the unit for 36 hours, and later release as negative -to- date.

What would CAP say if I implemented this? We are CAP accredited....

[Colin Barber]

Liz glad to have been able to help.

[LaraT23]

I loved the 7 day platelets! Our blood supplier had no issues at all during the pass port study, and thinks that there may have been other factors involved that were specific to the site with the pos cultures. It is just sad that the FDA would just put the kibosh on a 7 day platelet without really looking into the results. It now a waste of a valuable and sometimes difficult to get product. The holidays are going to be a challenge to keep pheresis donors coming in.

[Frances Haas]

We buy our products from UBS and we did use the 7 day shelf life platelets. UBS decided to go the safest route and get and go back to a 5 day shelf life. I understand the concern, but the longer shelf life was worked very well for us. We all liked it and no patient had adverse affects from these platelets.

[SMW]

What would CAP say if I implemented this? We are CAP accredited....

If you're in the US, it would not be acceptable.

[SMW]

..... It is just sad that the FDA would just put the kibosh on a 7 day platelet without really looking into the results. ......

As a reminder, the FDA approved the PASSPORT study, but it was the vendors of the collection systems that pulled the plug when preliminary results showed study criteria would/could not be achieved.

[Liz]

Unfortunately, very true..

**REVISED** 06/17/2010

TRM.44950

Platelet Component Storage

Phase II

Platelet components are stored at 20-24° C with appropriate agitation and transfused within the FDA-approved storage time for the particular container and collection method used.

NOTE: Storage of Platelets above 24° C may result in undesirable metabolic changes. Platelet storage below 20° C, even for brief periods, may cause irreversible declines in platelet function. . Platelet bags currently approved and used for 5-day storage maintain adequate platelet viability and function for up to 7 days. However, concerns that contaminating bacteria may proliferate to dangerous levels during prolonged storage have reduced the allowable dating period to 5 days. Agitation during storage is necessary to ensure optimal gas exchange and maintenance of pH.

Data in the literature suggest that platelets may be stored up to 24 hours without agitation. However, platelet bag manufacturer instructions must be followed if more stringent.

REFERENCES

1)

Shelton JB, et al. The effects of early agitation on the viability of stored platelets. Am J Clin Pathol. 1997;108:352-353

2)

Silberman S. Platelets. Preparations, transfusion, modifications, and substitutes. Arch Pathol Lab Med. 1999;123:889-894

3)

Moroff G, George VM. The maintenance of platelet properties upon limited discontinuation of agitation during storage. Transfusion. 1190;30:427-430

[Colin Barber]

Liz,

Bacterial contaimination of platelets is always a potential problem as they are stored at a controlled 22oC and I do remember a very sad case when I work for the National Blood Service in the UK which resulted in a patient death - this was using standard 5 day expiry pooled platelets.

I have to say it's sad if we can't move on though, surely we can learn and adapt our procedures to reduce risk - with transfusion of blood and components from one human to another there is never zero risk.

In medicine if we allow historical poor outcomes stop development and inhibit change we will ultimately not benefit our patient's. No one wants to have unsafe or dangerous procedures, products or medicines but I think sometimes the regulatory authorities concentrate on the wrong area's of risk. I so often feel we are put under intense survalence to justify, check, train, record keep in the Lab and then our products go out into the clinical area's and anything can happen and often does which puts patients at more danger.

I have contacted colleagues in our National Blood Service to try and get more details of the methods they use for bacterial screening and will share their reply, which sadly does sound like it will help you.

Best Wishes,

Colin

[Liz]

Dear Colin,

Thank you so much for furthering the investigation. I just adressed my chair to have his thoughts.

Merry Christmas.

Liz

[Colin Barber]

Liz,

NSHBT in the UK have just relaesed this information on Bacterial testing of Platelets.

Regards,

Colin

Information to hospital transfusion teams about bacterial testing of platelets17111.pdf

[Liz]

Liz,

NSHBT in the UK have just relaesed this information on Bacterial testing of Platelets.

Regards,

Colin

Hello Colin,

Nice news.

Thank you very much. I just sent it to the chair. I hope, but strongly doubt, that I can apply it as we are CAP accredited.

Liz

[rravkin@aol.com]

Collin,

In the article you present it seems that much of the predictability of contamination of a unit of platelets rely on the initial culturing (when the unit is first established) for bacteria which is not complete by the time the platelet unit is distributed and/or transfused. As such there is still a question of contamination prior to transfusion, especially when the shelf life is extended to 7 days. The article does not seem to address this issue as the initial culture may remain incubated at this time. So, is it possible that the initial concentration of bacteria potentially present in a unit of platelets will fall below the initial culture sensitivity capability for greater than seven days and yet increase to clinically significant levels in the unit itself on the seventh day where bacterial testing is or is not performed? I thought that recommendations stated that testing for bacterial contamination prior to transfusion was the primary focus. If we test for bacteria using culturing methods their detection capability inherently can not always, or reliably, identify clinically significant levels prior to transfusion. Furthermore I would ask if the platelet unit is capable of becoming contaminated during it's shelf-life? If it can then the initial culturing is again potentially incapable of preventing the transfusion of contaminated platelets. In closing there still seems to be a need for a testing system that will detect clinically significant concentrations of bacteria immediately prior to transfusion. I thank you in advance for any consideration and response.

I cann't wait for the day when we can use a handheld scanning device, like on Star Treck, to detect clinically significant levels of bacteria in units of platelets.:)

Edited January 19, 2011 by rravkin@aol.com