Melanoma - Oncept - July 2023 - Update post 216

[iberianfan]

Just chiming in for the record. We had our 6 month dose of Oncept and thorough check for melanomas. The remains the same one on his sheath as was present after the loading phase. And two tiny bumps under his tail. That’s it.

For those that haven’t read upthread, this horse had surgery with full anesthesia almost two years ago to remove about 14 melanomas on his sheath and little ones under his tail. when we checked him 4 months later, he already had 4-5 on his sheath. That’s when I started him on Oncept. This last dose was a year after the loading doses.

So it remains a a success story for me. I hope you guys are having as much success.

[iberianfan]

How is your horse doing??

[oldernewbie]

A good but kinda boring update from Mr Ay-rab’s visit to OSU yesterday. Everything looks stable and he got his injection. He did have to have some extra work done because he’s been having trouble lifting his hind feet for the farrier. Of course I went immediately into worst case scenario mode (he’s neurologic! there’s a melanoma pressing on his spinal cord! eeekeeeekeeeek!) but the problem seems to be just garden variety arthritis in his hocks. Whew!

I reeeeeally need to take it easy on the ruminating!

[Kyrabee]

No kidding oldernewbie. My mare is 20 with the run of the mill melanomas on her tail. A couple weeks ago, I went to the barn and found her to be bleeding rectally . WTH? I immediately went to an internal melanoma that ruptured some blood vessels. Whisk her to the vet and near as she could tell, she had a hemorrhoid (varicose vein) that had ruptured then closed off. Say what? She had quit bleeding by the time we got to the vet. She found no masses or tears. But yeah, I went right to the big nasty internal melanoma. I haven’t really got the $$ to do Oncept right now. I think I will have to do something soon to at least de-bulk the worst ones. Nothing is that large or interfering with any bodily function so far. She has had no recurrence of any bleeding thank goodness and fingers crossed it stays that way.

Susan

[oldernewbie]

Rumblings of supply chain issues with both the vaccine and the injector. Will post more when I know more! But since Mr Ay-rab is due for another injection in Dec/Jan, this makes me slightly panicky!

[iberianfan]

We are due at that time, too. Ugh.

[oldernewbie]

Mr Ay-rab got his latest injection on Christmas Eve in the comfort of his own stall! It is a huge help to have a family member who is a vet and who was able to get an injector and the vaccine. He is doing well - his lumps are doing their usual waxing and waning but nothing is causing any problems at this point. I think the growth in his eye is larger but he still seems to see well. The ocular melanoma still looks nothing like some of the images I found when I googled equine ocular melanoma - those are truly scary.

There is a new injector for Oncept for horses. It is still intradermal but does not make such a loud bang and does not need an adaptor.

If the universe cooperates, I do plan to take Mr A back to OSU in the summer for a complete lookover.

Just a side note - it’s now been 9 (!) years since Mr A’s first Oncept injection. I know he wouldn’t be with us today if it weren’t for Oncept and I am thankful!

Happy New Year!!!

[iberianfan]

We are having continued success as well. Had our 6 month dose Monday and virtually no change. So we are 2 years in from starting Oncept. Even if it stops working, that’s 2 healthy years added. I, too,am super grateful.

[WavyRider]

Just want to pop in and say thank you all for sharing your experiences! I am the owner of a wonderful 9yo gray gelding who has some small melanomas and I will definitely be referencing this thread as I continue to monitor and possibly treat them.

[MeghanC]

I’m also a newbie in this world of melanomas. I have a 10 year old grey ISH who had a few sarcoids cryo-ed a couple of years ago but now he has what looks to be dermal melanomas on his back. I was considering joining a trial at UGA vet school for another agent but my interest has waned when I heard that there will be “wound beds” that may take 1-2 months to heal. Does Oncept also produce wound beds in its action? Has it resulted in melanomas disappearing over time or does it just halt their growth typically? There is a LOT to learn! Thanks for any insight!

[oldernewbie]

Hi @MeghanC!

The only “wound” with Oncept is a small area shaved to the skin for the vaccine administration and a 1/2" diameter (maybe) round impression from the injection. The injection is intradermal (through the skin) so there are a few dots in the impression where the vaccine is shot into the skin with air. This round area has been very slightly raised when the vaccine has been administered to my horse. The raised area lasts a few days? With more than 20 injections so far, my horse has never had a negative reaction to the injection.

Yes, Oncept does cause some of the melanomas to disappear, apparently if they aren’t too large to begin with. I think it has been less successful with large erupting melanomas. It also halts or slows the growth of others. My horse has some that have gotten slowly larger, but very very slowly over 9 years. Others did disappear and never came back. OSU reports that about 50% of the horses they use the vaccine on show improvement. No way to know which ones will be helped until you give it a try - I think the standard trial is 4 injections.

Hope that helps. OSU (Ohio State U) has 50+ horses on Oncept now so they are a great resource if you’d like to get more info.

Good luck and ask away, always happy to help if I can.

[iberianfan]

What @oldernewbie said!! My horse had a half dozen or so fairly small ones when we started . All but one was gone after the initial doses. That one remains but with no noticeable growth. My horse has had no reaction to the vaccine and no sores/ wounds.

[Luska]

Hello @oldernewbie!
I found this conversation while I was looking for any possible treatment for my 15 yo PRE. A week ago we found melanoma in a right guttural pouch. I’m not sure how advanced it is… It was a preventive examinations, while we found such a ‘surprise’. He is in a very good condition with no signs of any disease in a body.
Today we start Cimetidine treatment.
I would also like to try Oncept. Would do anything for him no matter the cost…
Do you think you can help me to contact any vet for the diagnostics? I hope it is possible to send Oncept to Poland…

I hope you and Ay-rab are doing well
Joanna

[Fiesta01]

No personal knowledge, just wanted to send jingles for your boy. I’m sure others with experience with Oncept will chime in soon. Hang in there.

[NaturallyHappy]

I believe The Ohio State University Veterinary Medical Center in Columbus, OH does work w melanoma. I think Purdue University in Indiana may, as well.

[oldernewbie]

Hello @Luska!

Some time ago a fellow gray with melanoma owner from Austria posted here. So I know vets in Europe can obtain Oncept. Let me see if I can find her name…

Just for the record - cimetidine was tested on a very small population (3 horses I think?) with weak results. I used it for a while on Mr Ay-rab but discontinued it once he was on Oncept. It maybe worked a little? for a short time? but my advice to people since then has been to save their money and use Oncept.

Also, if you look upthread I link to a couple of review articles that cover all of the treatment options for melanoma. You have to pay to look at the older article but the more recent one is free. I would
recommend reading those.

Good luck and let me see if I can find the person from Austria.

ETA: Here’s the reference for the recent article. The authors are from Switzerland so that might be a good place to start. Google this:

Equine Melanocytic Tumors: A Narrative Review
José Pimenta, Justina Prada and Mário Cotovio

ETA2: The person from Austria is @Boerlin27. She hasn’t posted for a long while, but maybe worth sending her a message?

[Luska]

Thank you a lot. I will try Oncept if only possible.
The very first problem is to find a horse oncologist in the US who may help me send it to any European or non-European country (any place I can reach by car).
Oncept is forbidden in European Union now…
Thank you a lot for your help and article

[oldernewbie]

@Luska

Besides the authors in the article cited above, here is another group from Germany that tested Oncept:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7848327/

In my humble opinion it may be very productive to contact the authors of either paper to see if they can help you. Especially the group in Germany - they had to be getting the Oncept from somewhere. I have found most academic researchers to be very helpful when I contacted them.

Good luck!

[hoopoe]

@Luska. It is highly unlikely that a US Vet would ship a drug whose distribution is restricted, for what is technically off label use. That would certainly go many ways wrong and is not worth losing a license or a working relationship with the folks who produce the product .

Strongly echo the suggestion to have your vet contact the authors of the cited papers about possible treatments. There may be ongoing clinical trials which are usually done in association with a vet school.

Another resource would be to contact Merial directly for information on European support

[oldernewbie]

Mr Ay-rab’s favorite family vet gave him his injection today. We tried the injection in his pectoral for a change of pace. He also got a touch of happy juice just to make things go more smoothly. He was a champ as usual. All lumps stable. He has many lumps on his penis these days but they are small and do not interfere. Same is true for lumps under his tail. His eye looks about the same. So, for a guy of 17, he’s doing well.

We were much more organized and prepared this time. Last time I forgot a disposable razor, which we planned to use to shave the injection site. Ended up having to go into the family farmhouse and steal my sister’s razor. Yes, we were rather “backyardigan” as my niece the vet said. It was also very very cold! We got it done though.

Thankfully weather was great today, we had all the necessary supplies, so a success!