Re: changing immunotherapy vaccines

emma o'connor — Sun, 12 Jun 2011 10:24:31 GMT

Thanks all for such speedy replies and a big thanks to you Graham for all your information which has proved very helpful. This dog has been clinically stable for a long time, and as such, if there is a chance that I may 'rock - the- boat' by changing product I think I will have to have a full and frank discussion with the owner first.

Emma

Re: changing immunotherapy vaccines

Graham Bilbrough — Sun, 12 Jun 2011 09:28:55 GMT

Hi, Emma

There is no short answer to this question. Sorry.

As I understand the prescribing cascade, unless you have clinical justification supported by peer-reviewed papers, you should select a product that has Marketing Authorisation (MA) from another EU member state before one that no MA. There are no UK products with MA for allergen specific immunotherapy (ASIT); Artuvetrin has the only MA within the EU; and the two big US brands, Greer (as used by Axiom) and Heska, do not have MA. I believe that Artuvetrin, Greer and Heska are all have very good and similar clinical efficacy. Meanwhile, Artuvetrin has an easier-to-do induction protocol.

At this time, if you have clinical justification, you can use Greer and Heska immunotherapy, but you need to obtain an STC (Special Treatment Certificate; each pet's initial application must be done in paper and paid for). As Artuvetrin (as offered by IDEXX, SENSITEST and others) has MA from the Netherlands, you should use the other type of import certificate, known as a Special Import Certificate (SIC). This is free-of-charge and available immediately on-line.

In my humble opinion, for a new patient the situation is clear: use Artuvetrin, either directly or by one of the reference labs offering their products.

But, for a patient on existing therapy, I think things get somewhat more complex. For me, the biggest problem is that each year a proportion of those dogs doing well on immunotherapy will "step backwards" for reasons unrelated to their immunotherapy e.g. the dog comes into contact with fleas again, the owner changes the shampoo etc. However, if you have changed the ASIT that has worked for years, the owner will doubtless blame your new bottle.

The manufacturers of ASIT all recommend that you go back to the induction protocol when changing supplier. The Artuvetrin immunotherapy induction protocol is relatively painless, but this still needs to be considered--it means more visits to the clinic for the pet owner. Many vets are using an abbreviated protocol and I would be happy to discuss these on the telephone, but I cannot make a recommendation to use them as they are not detailed on the product's datasheet.

The decision to switch needs to be based on the allergens in the immunotherapy. For example, if it is a order of 3 or 4 commonly used allergens, it will be a simple task: Artu will be able to match them and will likely use the same source allergens--I'd have little concern about the switch. However, there are occasions when an exact match cannot be found, and then there are more questions to ask. Also, the two companies have different pricing structures.

When Heska's ALLERCEPT testing moved from CVS Axiom to IDEXX Reference Laboratories, many customers moved their allergy testing services and, although the approach varied from practice to practice, here is the commonest policy on immunotherapy:

1. All new patients start on the product with MA i.e. Artuvetrin

2. Switch clients with an "easy list" of allergens

3. Continue to use CVS Axiom for orders of >8 allergens or where Artuvetrin does not offer a complete match. Continue with Axiom for clients where you would be very nervous to "rock the boat". However, you would need to ask the VMD for clarification as to whether this counts as clinical justification. But, the most important thing here is your patient and nobody wants to see the dog scratching again for the sake of bureaucracy..

This is a complex area and I'd be happy to chat on the telephone, even if you're not an IDEXX client. If you ring the Wetherby lab (01937 544 000) they will put you through to me.

A few years back, CVS Axiom changed their supplier of immunotherapy from Heska to Greer. Many vet clients were seemingly unaware that this had happened and lots of dogs were switched from one brand to another (the bottles look very similar) and I am not aware of that causing any clinical problems. Switching immunotherapy is not quite as scary as the above text may make it appear!

I'd be interested to hear the thoughts of others.

All the best

Graham

Re: changing immunotherapy vaccines

Anthony Todd — Sun, 12 Jun 2011 09:26:07 GMT

[quote user="Emily Nightingale"]I would re-order the Axiom though. If it aint broke, don't fix it.[/quote]

I strongly agree. We changed from Axiom and the new one it didn't work at all!

Re: changing immunotherapy vaccines

Emily Nightingale — Sun, 12 Jun 2011 09:16:40 GMT

ooo that's a tricky one. I would be tempted to stick to the Axiom ( only ever used Artu myself), as you may be rocking the immunology boat by adding in different allergens ( I know you would choose same profile but allergen sources and make up may differ eliciting a different and new immune response)

Ultimately re cost and STC etc, if the client can afford axiom then should be able to afford the STC- and ordering new Artu can take up to 3 weeks which may put your protocol out of kilter.

Call Artu and Axiom for advice also- Artu are always really helpful when I have been stuck.

I would re-order the Axiom though. If it aint broke, don't fix it.

Good luck!